The temporomandibular joint is a unique bi-condylar joint involved in mastication and speech. Temporomandibular joint disorders (TMD) have a range of symptoms, including aural symptoms, and are present in approximately 75% of normal populations. The present study examined the relationship between signs and symptoms of TMD and mouth opening, gender, joint and aural symptoms, and hearing loss.The study involved 464 healthy Greek university students (156 men and 308 women) with a mean age of 19.6 years. Age, gender and maximum mouth opening was recorded. Mouth opening was measured using Vernier calipers. An anamnestic questionnaire was used to stratify the subjects into four groups based on TMD severity. Aural symptoms and an audiogram were recorded for each subject too. Data were analyzed using multifactor ANOVA, chi-square, t-test, Mann-Whitney and Kruskal-Wallis tests.The overall incidence of TMD signs and symptoms was 73.3%. The incidence and severity was greater in females than males . The number of aural symptoms was associated to the TMD severity  as well as maximum mouth opening . Audiometry showed that moderate and severe TMD was associated with hearing loss of median and low tones respectively . TMJ pain , TMJ ankylosis , bruxism  and ear itching  were also found to be statistically different between TMD and non-TMD subjects.TMD signs and symptoms were more common and severe in females than males. TMD severity is correlated with the degree of mouth opening and the number of aural symptoms. The absence or presence of mild TMD are associated with normal audiograms while moderate and severe TMD are related to hearing loss in median and low tones respectively. Bruxism, joint ankylosis, joint pain and ear itching were more common in TMD than non-TMD patients. The temporomandibular joint is critical for normal mouth function, and thus plays a role in chewing, swallowing, speaking, oral health and nutrition. The temporomandibular joint is a synovial joint containing an articular disk which allows for hinge and sliding movements. The articular surfaces are covered by avascular and non-innervated fibrocartilage which has a high regenerative capacity. The temporalis and masseter muscles control joint's motion.The term temporomandibular disorders (TMD) is a collective one, representing a sub-classification of muscle-skeletal disorders, and more specifically a number of signs and symptoms involving the masticatory muscles, the temporomandibular joint and associated structures. It is estimated that about one third of adults have TMD symptoms . TMD hasThe maximum mouth opening distance is a generally accepted measurement to estimate temporomandibular joint mobility and function . Mouth oAural symptoms such as tinnitus, otalgia, dizziness or vertigo, otic fullness sensation, hyperacousia or hypoacousia are thought to be associated with TMD ,7, whileThe present study examined 464 healthy young Greek adults for the presence of TMD signs and symptoms. The study analyzed data for probable correlations between TMD severity and range of mouth opening, aural and joint symptoms and hearing loss. A feature of the study was the use of audiography to objectively assess the co-existence of hearing loss and TMD.The study was performed in the Laboratory of Anatomy at the Medical School of the University of Ioannina. The project involved 464 volunteers  aged from 18 to 26 years (mean age 19.6 years) who attending the University of Ioannina. All volunteers were healthy, without active disease or craniofacial anomalies.Maximum mouth opening (mm) was measured using a 1 mm calibrated Vernier caliper. Subjects opened their mouths as wide as possible, and the inside jaws of the caliper were used to measure the interincisal distance . During measurements, subjects were seated in a chair with head supported and held in the anatomical position in order to control for additional movements of the cervical, thoracic and lumbar spine . Only thAt the completion of the measurement, the gender and age of each subject was recorded. Temporomandibular symptoms were assessed using a validated self-report anamnestic questionnaire composed of 10 questions . The queUsing another questionnaire, subjects were asked whether they had experienced the following aural symptoms: a feeling of fullness or pressure in ear, brief vertigo (less than 5 minutes), cold and warm air sensitivity, itching of the acoustic canal, and a history of diagnosed hearing loss, more than four events of otitis, tinnitus or ear pain. Subjects were categorized based on having none or less than two of those symptoms, more than two of the above symptoms, and more than four of the aforementioned symptoms.After completing questionnaires, the volunteers were taken to a separate room where tympanometry and pure tone audiography were conducted to objectively evaluate hearing loss. Pure tone audiography included tones between 125-8000 Hz. All subjects were found to be normal in terms of tympanometry results . Each auAll subjects gave written informed consent regarding participation and publication of the data. The study was approved by the Ethics Committee of the Medical School of University of Ioannina.Our variables for analysis were the age, the gender, the number of aural symptoms, range of mouth opening, and the degree of qualitative and quantitative hearing loss. ANOVA and t-tests were used to compare normally distributed variables, and Kruskal-Wallis and Mann-Whitney tests were used for comparing non-normally distributed variables . Chi-square test was used to compare both normally and non-normally distributed variables. We also investigated for correlations between TMD severity and bruxism, joint ankylosis, joint pain and ear itching using chi-square testing.Analysis was performed on anonymous data using SPSS version 18. Kolmogorov-Smirnov and Shapiro-Wilk tests of normality were employed to determine data distribution. The level of statistical significance was p < 0.05. The confidence interval was 95%.Of the 464 study subjects, 73.3% were diagnosed with TMD, and 26.7% were diagnosed as not having TMD. Of the 340 TMD subjects, TMD was classified as mild in 31.76%, moderate in 40% and severe in 28.2%. In addition, the incidence and severity of TMD was greater in women than men (p < 0.05). The mean mouth opening was 46.56 mm in men and 44.43 mm in women . The range of mouth opening was greater in men than women . Analysis of mouth opening distance in the four TMD groups showed that the mean mouth opening was 46.45 mm in the non-TMD group, in the mild TMD group 45.37 mm, 44.07 and 44.43 mm in the moderate and severe TMD groups respectively. Kruskal -Wallis analysis indicated that mean mouth openings differed significantly between the TMD groups (p < 0.05)  History of temporomandibular joint ankylosis was reported by 52 subjects. It was referred by 3.7% of mild, 2.9% of moderate and 45.8% of severe TMD subjects. No non-TMD participants had joint ankylosis. Chi-square test found that joint ankylosis was more likely to be found in TMD patient than non-TMD subjects (p < 0.05). Bruxism was reported by 80 subjects. It was recorded in 0% of non-, 7.4% of mild, 29.4% of moderate, and 33.3% of severe TMD patients. Chi-square test showed that bruxism was more likely to occur in TMD than non-TMD subjects (p < 0.05). Ear itching was reported by 92 subjects. It was experienced by 12.9% of non-, 11.1% of mild, 26.4% of moderate and 29.1% of severe TMD subjects. Chi-square test revealed that ear itching differed between TMD groups (p < 0.05). Ear itching was commoner in TMD than non-TMD subjects  or mild TMD (70.4%) subjects had no aural symptoms. For the moderate TMD group, 55.9% had none and 38.2% had more than two aural symptoms. In the severe TMD group, 25% had more than two and 29.2% had more than four aural symptoms. Chi-square test showed that the severity of TMD is related to the number of aural symptoms. Qualitative assessment showed that 51.7% of the subjects had normal hearing, 13.8% and 18.1% of the subjects had unilateral and bilateral low tones loss respectively, and 8.6% and 7.8% of the subjects had bilateral and unilateral median tones loss respectively. We analyzed qualitative hearing loss and TMD groups using chi-square test. We found that TMD severity was correlated with hearing loss (p < 0.05). Most subjects without hearing loss belonged to the non-TMD group (46.6%), while most subjects with low tones hearing loss in both ears belonged to the severe TMD group (47.6%). For median tones, hearing loss in both ears was more common in moderate (50%) compared to severe TMD (40%) subjects. Furthermore, most mild-TMD subjects had no hearing loss (59.3%), Quantitative assessment using audiograms showed that 61.2% of the subjects had ≤15% hearing loss in both ears, 22.4% had > 15% loss in one ear, 5.2% had > 15% loss in both ears, 6.9% had ≥20% loss in one ear and 4.3% had ≥20% loss in both ears. Chi-square test showed that there was a relationship between TMD severity and degree of hearing loss (p < 0.05). Most non- and mild TMD subjects had ≤15% hearing loss. For the severe TMD group, 25% had no hearing loss, 16.7% had > 15% loss in one ear and 16.7% had > 15% loss in both ears, 20.8% had ≥20% loss in one ear, and 20.8% (n = 20) had ≥20% loss in both ears Tables .The present study examined the relationship between TMD symptoms and signs and mouth opening, gender, aural symptoms, temporomandibular joint pain, temporomandibular joint ankylosis, bruxism and hearing loss.We found that 73.3% of the young Greek adult population examined in this study had TMD symptoms and signs. This finding is consistent with previous studies involving college students ,16. CompWe found that mouth opening differed, according to TMD severity, and the least opening was observed in the severe TMD group. Interestingly, we found that while mouth opening was less in severe TMD subjects (44.43 mm) compared to non-TMD subjects (46.45 mm), it was greater in severe TMD subjects than moderate TMD ones (44.08 mm). It has already been reported that joint hypermobility is often present in TMD patients . Mouth oEthnicity is believed to affect the degree of mouth opening ,17. The We found that TMD was more prevalent and severe in women than men. This observation is consistent with previous studies, as it has been reported that women present an increased risk of 1.5-2 or 2-9 times compared to men to develop TMD .The current study found that pain in the temporomandibular joint was the most common symptom 27.05%) of TMD as reported elsewhere 7.05% of . The incJoint sounds are regarded as the commonest sign of TMD (13.5%) , and areWe found that bruxism was present in 27.02% of those with TMD and in none of the non-TMD subjects. Others reported that bruxism was present in 7.4%-27.2% of TMD subjects . BruxismHead and neck ache may be of neurological, vascular, muscular, ligamental or bony origin. The temporomandibular joint has muscular and ligamentary connections to the cervical region forming a functional complex. Headache is regarded as the most common symptom (22%) of TMD patients , while 5We found that TMD severity is correlated with the number of aural symptoms. Costen, in 1934, firstly associated aural and craniosinusal symptoms with TMD, and named it Costen's or Otognathic Syndrome . We obseThe second theory involves the tiny ligament called the discomalleolar or Pinto's ligament, which originates from the anterior malleolar process, passes through the petrotympanic fissure and inserts in the medial and posterosuperior part of the articular capsule and the disk ,35. In dThe third theory proposes that common innervation of the tensor veli palatini, tensor tympani, masseter, temporalis and pterygoid muscles by the motor nucleus of the trigeminal nerve is the underlying cause of the aural symptomatology in TMD patients . Tensor Furthermore, every movement of the neck or jaw exerts tension on the carotid sheath, increasing the endolymphatic pressure of the hair cells in the cochlea via impedance of the saccus endolymphaticus' pressure-regulating mechanism, causing tinnitus and vertigo . In bruxThe results of a previous study suggested that TMD peripherally sensitizes the V and VII pairs, leading to tonic spasm of these middle ear muscles. This process may cause low tones hearing loss. We found that severe TMD was associated with low tones hearing loss, while moderate TMD correlated with median tones hearing loss. Furthermore, the degree of hearing loss increased with TMD severity. In a study of 44 TMD patients, ear fullness was recorded in 13.6%, vertigo in 13.6% and hearing loss in 6.8% of the subjects. In that same study, audiometry revealed a sensorineural hearing loss in only one subject, at 28-30 dB . Other sFinally, the fourth theory proposes that psychosocial disorders are responsible for the co-existence of aural symptoms in TMD patients .The limitation of our study is the absence of clinical diagnosis of TMD. No clinical examination or other laboratory findings confirmed or rejected each participant's score according to his anamnestic questionnaire. The tool employed only describes signs and symptoms of TMD which may not be seen as a synonym of TMD presence. Thus, many volunteers of this study could not be diagnosed as TMD patients. For the convenience of the results' interpretation we stratified our subjects in four TMD severity groups referring to the number of TMD signs and symptoms. Nevertheless, the results of several studies based on such data verify the utility of evaluation via only an anamnestic questionnaire ,28.The present study found that TMD severity was associated with gender (more common and severe in women), range of mouth opening, the number of aural symptoms, ear itching, temporomandibular joint ankylosis, temporomandibular joint pain, bruxism and qualitative and quantitative hearing loss. The close embryological, anatomical and functional relationships between the temporomandibular joint and the middle ear may explain the link between aural symptoms and TMD severity. A feature of the present study was the use of audiometry to assess hearing loss in TMD. Finally, this is the first study to measure mouth opening in young Greek adults.The authors declare that they have no competing interests.PK conceived of the study and participated in its design and coordination. AM and VG carried out the measurements and drafted the manuscript. KI carried out the statistical analysis of the study. AZ, PK and GP participated in the interpretation of the data and in the design and coordination of the study. All authors read and approved the final version of the manuscript.The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1472-6815/11/5/prepub


There is need for a brief but comprehensive objective assessment tool to help clinicians evaluate relapse symptoms in patients with multiple sclerosis (MS) and their impact on daily functioning, as well as response to treatment. The 2-part Assessing Relapse in Multiple Sclerosis (ARMS) questionnaire was developed to achieve these aims. Part 1 consists of 7 questions that evaluate relapse symptoms, impact on activities of daily living (ADL), overall functioning, and response to treatment for previous relapses. Part 2 consists of 7 questions that evaluate treatment response in terms of symptom relief, functioning, and tolerability. The ARMS questionnaire has been evaluated in 103 patients with MS. The most commonly reported relapse symptoms were numbness/tingling (67%), fatigue (58%), and leg/foot weakness (55%). Over half of patients reported that ADL or overall functioning were affected very much (47%) or severely (11%) by relapses. Prescribed treatments for relapses included intravenous and/or oral corticosteroids (87%) and adrenocorticotropic hormone (13%). Nearly half of patients reported that their symptoms were very much (33%) or completely resolved (16%) following treatment. The most commonly reported adverse events were sleep disturbance (45%), mood changes (33%), weight gain (29%), and increased appetite (26%). Systematic assessment of relapses and response to relapse treatment may help clinicians to optimize outcomes for MS patients. Multiple sclerosis (MS), particularly relapsing remitting MS (RRMS), the most common form of the disease, is characterized by relapses , 2. Thes Assessment tools, such as the Expanded Disability Status Scale (EDSS)  and MultThe Assessing Relapse in Multiple Sclerosis (ARMS) questionnaire is a 2-part patient self-report assessment tool that was developed by a panel of expert MS nurses and is specifically designed for evaluating relapses and responses to relapse treatment . Part 1 This phase 4, pilot, cross-sectional descriptive/exploratory study was conducted at 5 clinical practice sites in the United States to assess the psychometric properties of the ARMS questionnaire in adult patients with MS experiencing a relapse .  http://dx.doi.org/10.1155/2013/470476) is a 2-part, 2-page survey, with each part comprising 7 questions. Part 1 was completed when a patient presented with a new MS relapse to evaluate the patient's relapse symptoms and how the symptoms affect activities of daily living (ADL) and overall function, as well as the patient's response to past treatments for previous relapses, as a means of guiding treatment selection (the choice of relapse treatment was entirely at the discretion of the treating clinician and did not affect patient eligibility). Part 2 was completed 1 month (±1 week) after initiation of treatment for relapse to evaluate the treatment response in terms of symptom relief and functioning, as well as tolerability. Each part of the questionnaire was completed by the patient or by the investigator . Questionnaires could be completed in the office or via telephone.The ARMS questionnaire  was determined, using the three inter-related questions regarding response to relapse treatment. In Part 2, for example, questions 4 (symptom improvement), 5 (ADL), and 6 ) were evaluated. The TCS was calculated as the sum of the scores for these items. For this analysis, the score for the ADL item was calculated as 10 minus the value of the rating indicated by the patient, such that higher score values and greater positive changes from baseline indicate better functioning/improvement. Thus, for the TCS, the sum of the responses of the three questions has a range of 0 to 30, with higher scores indicating greater improvement/better functioning. The TCS was summarized descriptively. The distribution of the mean TCS was computed, and the 95% two-sided confidence interval for the mean TCS was computed based on Students bach's α  was usedt-distribution. The internal consistency of the ADL and RSH questions in Part 1 and, separately, the ADL and RSH questions in Part 2, was examined using the Pearson correlation.Two questions  both specifically refer to ADL; the change in ADL was estimated based on these two questions; the score for each item was calculated as 10 minus the value of the rating indicated by the patient, such that higher score values and greater positive changes from baseline indicate better functioning/improvement. Two other questions  both specifically refer to return to previous state of health (RSH); the change in RSH was estimated based on these two questions , with higher scores indicating a more complete return to previous state of health. Changes in ADL and RSH scores were summarized descriptively. The distribution of the mean change in ADL and RSH scores was also computed. The 95% two-sided confidence interval for the mean change in ADL and RSH scores was computed based on Students t-distribution. The change in the PCS was also computed and summarized, and the mean change was evaluated in the same manner as the PCS scores.An additional composite score ) was computed based on the sum of the ADL and RSH questions. The PCS was computed separately for Part 1 (new relapse) and Part 2 (after relapse treatment) and summarized descriptively; again, the scores for the ADL items were calculated as 10 minus the rating provided by the patient, such that the sum of the item scores has a range of 0 to 20, with higher scores indicating better functioning/greater improvement. The distributions of the PCS mean composite scores were also computed, and the 95% two-sided confidence interval for the mean PCS was computed based on Students The study included 103 patients. A summary of their demographic and clinical characteristics is provided in Characteristics of the current relapse are summarized in Most patients (82%) were treated with intravenous (IV) and/or oral corticosteroids for their last relapse; and 72% of all patients indicated that they were very much improved or completely returned to their baseline state of health after treatment for their last relapse . The advAll 103 patients who completed Part 1 of the ARMS also completed Part 2. The majority of follow-up assessments were conducted by phone (74%), and the majority of questionnaires were completed by office staff (79%).The majority of patients were treated with corticosteroids for their current relapse (87%). Adrenocorticotropic hormone (ACTH) was the only other treatment reported (13%) . Nearly The most common adverse events reported were sleep disturbance , mood changes (33%), weight gain (29%), increased appetite (26%), increased fatigue (21%), headache (20%), and stomach upset (20%) . P = 0.035, Fisher exact test).Although the study was not designed or powered to evaluate differences between treatments, there were several notable differences between the corticosteroid and ACTH groups in the incidence of adverse events, including sleep disturbance (49% versus 15%), increased appetite (29% versus 8%), weight gain (32% versus 8%), and headache (23% versus 0%). Post-hoc analyses indicated a statistically significant difference between groups in sleep disturbance (P = 0.053), but scores in Part 2 were significantly correlated , suggesting that improvement in ADL is closely related to patients' perception of having returned to their prerelapse baseline.Mean scores for TCS, ADL, and RSH are summarized in α (0.87), suggesting good internal consistency among those 3 questions. The individual Cronbach α's for Question  4, ADL, and RSH with TCS were 0.84, 0.86, and 0.75, respectively. The corresponding correlation coefficients are shown in r = 0.60, P < 0.0001) and RSH ; and as previously noted, ADL was also significantly correlated with RSH .Analysis of the combined relationship of questions 4 (symptom improvement), 5 (ADL), and 6 (RSH) from Part 2 of the questionnaire with the TCS showed a high Cronbach α indicated high internal reliability and consistency among the three interrelated questions in Part 2 , 5 (ADL), and 6 (RSH)) and the TCS. High Pearson linear correlations indicated good internal consistency between the ADL and RSH questions in Part 2. The lower correlation between the ADL and RSH questions in Part 1 is not unexpected, as the ADL question refers to the effect of the current relapse on ADL, while the RSH question refers to the effect of treatment for the previous relapse. The ARMS questionnaire was developed by a working group of MS nurse experts from the United States and Canada, with the objective that it would be employed for the assessment of relapses and evaluation of response to relapse treatment. Results from this pilot study indicate that the ARMS questionnaire appears to be useful for evaluating relapses and response to acute relapse treatment. Cronbach's Results obtained with Part 1 of the ARMS questionnaire indicated substantial impact of relapses on patients with new appearance or increased severity of a large number of symptoms, including numbness/tingling, fatigue, leg/foot weakness, and difficulties in walking. Relapses also negatively affected ADL very much or severely in >50% of patients. This finding is consistent with prior results from a very large sample of MS patients which showed that those who experienced one or more relapses in the past 12 months had significantly greater functional disability than patients without relapses over this period . Part 2 Results from Parts 1 and 2 of the ARMS questionnaire indicated that corticosteroid treatment was associated with adverse events, including sleep disturbance, mood changes, and weight gain; all of these are well-known side effects of these agents . A smallThe ARMS questionnaire may complement other instruments that have been employed to evaluate the status of patients with MS. The Expanded Disability Status Scale (EDSS)  and MultSome aspects of the study design may be considered limitations. For example, the study did not employ strict inclusion or exclusion criteria, and the diagnosis of relapse was at the discretion of the investigator. However, the ARMS questionnaire is intended to be used in a broad range of patients and the study was designed to evaluate the questionnaire's ability to gauge the impact of relapses on patients and its ease of use to clinicians; as such, strict criteria to characterize relapses would limit the generalizability of the findings. In addition, we did not collect other clinical information that may be useful in evaluating differences in outcomes between patients . Finally, the study was not designed to compare outcomes with corticosteroids and ACTH, and the results should be considered with this in mind.In summary, the results of this pilot study suggest that the ARMS questionnaire can be used in clinical practice settings to evaluate relapses and response to relapse treatments. The ARMS questionnaire may help clinicians to accurately and conveniently assess the nature and impact of relapses as well as the effectiveness of their current approaches to treatment. Furthermore, it may assist in promoting patient-clinician dialogue about relapses and their management across a variety of practice settings. The Assessing Relapse in Multiple Sclerosis (ARMS) questionnaire is a 2-part self-report assessment tool developed by a panel of expert MS nurses and specifically designed for evaluating relapses and responses to treatment.Click here for additional data file.Click here for additional data file.


To investigate the performance of monaural and binaural beamforming technology with an additional noise reduction algorithm, in cochlear implant recipients.This experimental study was conducted as a single subject repeated measures design within a large German cochlear implant centre. Twelve experienced users of an Advanced Bionics HiRes90K or CII implant with a Harmony speech processor were enrolled. The cochlear implant processor of each subject was connected to one of two bilaterally placed state-of-the-art hearing aids (Phonak Ambra) providing three alternative directional processing options: an omnidirectional setting, an adaptive monaural beamformer, and a binaural beamformer. A further noise reduction algorithm (ClearVoice) was applied to the signal on the cochlear implant processor itself. The speech signal was presented from 0° and speech shaped noise presented from loudspeakers placed at ±70°, ±135° and 180°. The Oldenburg sentence test was used to determine the signal-to-noise ratio at which subjects scored 50% correct.Both the adaptive and binaural beamformer were significantly better than the omnidirectional condition (5.3 dB±1.2 dB and 7.1 dB±1.6 dB (p<0.001) respectively). The best score was achieved with the binaural beamformer in combination with the ClearVoice noise reduction algorithm, with a significant improvement in SRT of 7.9 dB±2.4 dB (p<0.001) over the omnidirectional alone condition.The study showed that the binaural beamformer implemented in the Phonak Ambra hearing aid could be used in conjunction with a Harmony speech processor to produce substantial average improvements in SRT of 7.1 dB. The monaural, adaptive beamformer provided an averaged SRT improvement of 5.3 dB. The performance of cochlear implant users continues to improve and many achieve good levels of speech perception, especially in quiet. Performance in noise however remains a challenge and manufacturers are constantly exploring different methods to improve it: Advances in the coding strategies used by the different devices, electrode design and the application of bilateral implants all contribute to improvements in performance Cochlear implant manufacturers have used a number of different algorithms to reduce noise in the processing pathway such as Adaptive Dynamic Range Optimisation, used in recent versions of the Cochlear device Beamforming works by exploiting phase differences in the signal arriving at two or more spatially separated microphones from a particular direction of incidence. After applying an appropriate delay, the inputs can be subtracted from each other and different directionality patterns can thus be achieved. Beamformers can be used to produce a static pattern of directionality, where the point of maximum attenuation or null is fixed or an adaptive one, where the null follows dynamically the direction of noise incidence. That means adaptive systems have the advantage of being able to suppress moving noise sources.In order for beamforming to work, a number of assumptions typically have to be met: the target should always be located within a narrow range on angles in front of the listener, and the target level should be identical at the two microphones. Well matched and calibrated microphones are essential and in reverberant rooms the performance has been shown to degrade, as both target and interfering noise become more spatially diffuse and consequentially more difficult to separate based on their directionality 2002) compared fixed directional, adaptive, and omnidirectional microphone programs in 20 hearing impaired users of the Phonak Claro hearing aid . They tested four noise conditions in a moderately reverberant room: (a) diffuse noise from 5 speakers at 750 intervals, (b) noise from 2 speakers at 1600 and 2000 behind the listener, (c) noise from speakers at 700 and 1100 to the side and (d) panning noise across all five speakers. Speech was always presented from 0° in front of the listener. The adaptive system was significantly better than the omnidirectional setting for all conditions, with a 2.9 dB improvement for sentences in diffuse noise. The fixed setting was only significantly better than the omnidirectional setting when the noise was presented from behind. The authors noted however that the fixed directional mode of the hearing aid used in the study was not optimised for diffuse noise, but noise coming from behind the listener. A systematic review of nine studies by Bentler in 2005 found evidence to support the effectiveness of directional microphones in current hearing aids Directional microphones have been effectively employed in hearing aids to improve user performance in noise 0 to the right or from three speakers placed at 30°, 60° and 90° to the right. Average improvements in percent correct scores over the unprocessed bilateral condition were 36% and 30% for the single and multiple noise sources respectively.When hearing aids with adaptive directional microphone systems are fitted bilaterally, each system operates independently of the other. This situation was investigated by Mackenzie and Lutman: The authors found that although the adaptive systems worked independently, there were no detrimental effects, as measured by sentence recognitions scores in noise or quality ratings While several studies showed significant benefits of binaural beamformers for CI users This study investigated the performance of CI recipients using beamforming technology, as implemented in Phonak Ambra hearing aids, when combined with the Advanced Bionics Harmony speech processor  in an experimental test setup. For this purpose the output signal of the Phonak Ambra hearing aid was galvanically coupled to the auxiliary input of the Harmony speech processor. The hearing aids used in this study implement a binaural beamformer using four microphones across the two hearing aids, producing a very narrow target beam and a monaural adaptive beamforming program called UltraZoom The effect of adding ClearVoice (CV) as a post-processing stage to all three microphone settings was also assessed. CV is a single-microphone noise reduction algorithm implemented in the Advanced Bionics speech processor The study showed that both the binaural beamformer and the monaural adaptive beamformer implemented in the Phonak Ambra hearing aid could be used in conjunction with a Harmony speech processor to produce substantial average improvements in SRT. ClearVoice added a further benefit.The study protocol was reviewed and approved by a registered ethics board . After explanation of the study protocol and the risks and benefits of participating, all subjects signed a consent form before taking part.12 postlingually deafened subjects with an Advanced Bionics HiRes90K or CII cochlear implant were recruited randomly at the Cochlear Implant Center to participate in the study. All subjects were regular users of the HiRes120 processing strategy and had a minimum experience with their current strategy and processor of three months. All subjects had word scores of more than 15% for sentences in noise in the last clinical test. There were no criteria for the contralateral ear and five subjects were bilaterally implanted. If a subject was bilaterally implanted, the side with the better speech intelligibility was used, determined by the routine sentence test data collected in the clinic. The other side was turned off. The contralateral ear was plugged in subjects with residual contralateral hearing.The mean age of implantation was 57 years, ranging from 30 to 72 years. The mean duration of deafness was nine years, ranging from zero to 30 years, based on the age when a telephone call was no longer possible till the age of implantation. The mean duration of cochlear implant use was three years, ranging from one to five years. Subject demographics are shown in Subjects were provided with an Ambra behind-the-ear (BTE) hearing aid which was placed ipsilaterally to the test side and connected to the speech processor, allowing the subjects to listen directly through the hearing aid. For the binaural beamformer condition a second hearing aid was placed on the contralateral ear, which was wirelessly linked to the other hearing aid connected to the speech processor . To connUsing the integrated pair of microphones of the modified hearing aid positioned at ear level, three different directional settings were programmed into the hearing aid:Omnidirectional (omni): In this mode, the signal of the omnidirectional front microphone is transmitted to the speech processor without further processing.The monaural adaptive beamformer (aBF): The aBF generates its directionality from one pair of microphones in the same device. It changes its directionality adaptively, based on the direction of noise.The binaural beamformer (bBF): The bBF generates its directionality using two pairs of microphones on two separate ears. Thus, when using the bBF, a second hearing aid was needed on the contralateral ear. The two hearing aids were wirelessly linked and one was connected to the CI as described above.Generally, CIs deliver time-staggered, amplitude-modulated electric pulse trains to an electrode array in the inner ear, where they excite the fibers of the auditory nerve. Current amplitudes are derived from the envelopes of a filter bank by the externally-worn speech processor and transmitted to the implanted circuit using a radio frequency link. For a typical user of the HiRes 120 coding strategy with 16 active implant electrodes, the number of filter-bank channels is 15, spanning a frequency range of approximately 250 to 8000 Hz a posteriori signal-to-noise ratios (SNRs), such that channels dominated by noise are dynamically attenuated. The background noise level is estimated using a voice-activity-dependent minimum tracking procedure. Channel-specific attenuations are determined based on a perceptually-motivated sigmoidal gain function. The highest possible attenuation per channel thus applied can be set to 6, 12 or 18 dB during fitting.ClearVoice is a noise reduction algorithm optionally available for users of HiRes 120. It applies attenuation to the output of each filter bank channel depending on the estimated During testing, input to the processor was provided solely from the auxiliary input connected to the hearing aids. Before testing the speech processor was set to a sensitivity of 0. The volume dial allowed the subjects to change their M-levels globally by ±50%. Two programs were created: i) the clinical program without CV, ii) the same program with CV medium and with the most comfortable listening levels raised by 5% (as described in 6). The medium setting of CV was used, limiting the maximum amount of attenuation to 12 decibels (dB). Prior to each test condition, the subject was allowed to adjust the volume for optimal perception.The adaptive beamformer is based on the approach proposed by Elko and Pong rd order (i.e. four-microphone) beamformer. The combination of signals across ears yields in a narrower and more focussed frontal and lateral beam pattern especially in the low-frequencies.The binaural beamformer requires two dual-microphone systems, one on each ear . First, Both microphone systems attenuate noise from rear and lateral angles while maintaining the signal level from 0° front, thus yielding in an improved signal-to-noise ratio compared to an omnidirectional microphone system. Since the binaural beamformer has a more focussed beam to the front, i.e., more attenuation of surrounding noise, more improvement of the signal-to-noise ratio is achieved than with the monaural adaptive beamformer.A quantitative measure of microphone directionality was derived from polar plots obtained for a hearing aid on the left ear of a KEMAR artificial head in an anechoic room using a single noise source from varying angles . The radAs a further method to obtain an objective estimate of the prospective performance benefit for both beamforming algorithms,the relative attenuation of diffuse speech-shaped noise signals was determined in the particular spatial setup of this study: noise was simultaneously presented from the five noise speakers, and its speech-intelligibility weighted attenuation relative to a subsequent speech signal from the front was determined . The SNR improvements thus estimated were 4.1 dB for the adaptive monaural and 7.6 dB for the binaural beamformer relative to the omnidirectional condition.The hearing aid was programmed with a flat frequency response, providing 0 dB gain for all levels, and only the respective directional processing algorithm active. All other features were turned off. Furthermore, the hearing aid output level was matched to the input sensitivity of the CI system.Acute speech tests were carried out over the course of two sessions, one to six weeks apart, in a low-reverberant, sound-damped room. Each appointment typically lasted approximately two hours including two breaks. Six different conditions were tested and two were repeated at the following appointment, as shown in The test set up was as shown in A single-subject repeated measures design was used where each subject acted as their own control. Parametric statistics were applied. Data from appointment A was compared with a repeated measures two-way ANOVA, with the factors microphone directionality (omni vs. aBF) and noise reduction (CV on and off). Data from appointment B was compared using a one-way ANOVA to test for the effect of processing scheme only . Where a statistically significant effect was identified by the ANOVA, pairwise comparisons were made using two-tailed t-tests with Bonferroni corrected p-values. Following each ANOVA six pairs of data were compared, therefore a correction factor of 6 was applied and all p-values given in the text or graphs are the t-test p-value outcomes multiplied by 6. Means are quoted with 95% confidence intervals.Individual results from all 12 subjects are shown in The results of the ANOVA are shown in This study was conducted to investigate the performance benefit of monaural adaptive and binaural beamforming technology with an additional noise reduction algorithm in unilateral CI users. As still a significant number of CI users is unilaterally implanted and generally unilateral hearing conditions do not allow spatial release from diffuse background noise The results of this study show that the use of beamforming technology significantly improved performance over the omni setting in diffuse noise in all conditions. The largest SRT improvement of 7.9 dB over the omni setting was observed for the bBF+CV condition. When looking at the effect of microphone directionality only, an SRT improvement of 7.1 dB was found for bBF compared to omni.The SNR improvements estimated by the speech-intelligibility weighted noise attenuation were 4.1 dB for the adaptive monaural and 7.6 dB for the binaural beamformer, which was broadly consistent with the differences in directivity indices relative to the omni directional condition (5.9 and 7.1 dB) and the improvements found in the study subjects in appointments A and B . Note that speech-intelligibility weighted attenuation was measured in the room and loudspeaker setup in which the subjects were tested, whereas the directivity index was measured with one single loudspeaker from different angles in an anechoic room. Different rooms and loudspeaker setups led to slightly different results between predicted SNR improvements and directivity indices. Nevertheless, both objective technical measures reflect more attenuation of noise with the binaural beamformer than with the adaptive beamformer, which is consistent with results obtained in subject testing.In comparison to the adaptive monaural beamformer, the binaural beamformer proved to be significantly more efficient. The SRT difference between the two algorithms was 1.9 dB, consistent with in-house testing at Phonak where, in hearing-impaired hearing aid users, a difference between binaural and adaptive algorithms of 2.4 dB (p = 0.012) was shown In the studies reported by Brockmayer et al The two-way ANOVA with the factors microphone directionality (omni vs. aBF) and noise reduction (CV on and off) revealed a significant main effect of 0.8 dB for CV which was independent from the microphone directionality. This means the CV benefit is additive to the beamformer benefit. The benefit is smaller than expected from previous studiesAccording to the experiences in the hearing aid field, the benefit of beamformers is probably smaller in real life than in laboratory studies. On one hand, limitations of the experimental designs used so far may explain this discrepancy. On the other hand, reported problems from directional microphone studies in the hearing aid field are not directly applicable to the world of CIs: CI users still usually have little or no residual hearing and as a consequence, receive only the processed signal; no unprocessed, acoustic signals through an ear-mould venting can disturb the hearing like in hearing aid subjects, which commonly reduces the benefit of directional microphones in conventional hearing aids In order for beamforming to be used effectively the CI user must have a good understanding of when to use the beamformer. The narrow directional pattern of the binaural beamformer allows to focus on a single target source located opposite the listener, eliminating sounds from the back, sides and even off-centre frontal angles. This may be the appropriate configuration for a face-to-face conversation in a noisy bar or restaurant. If, however, the target speaker was to move positions constantly as in the case of a typical round-table discussion, the use of the adaptive beamformer is likely to be more advantageous. In situations where speech and noise are not sufficiently spatially separated, a single-channel noise reduction algorithm such as CV can still improve the listening performance.When speech intelligibility is very difficult due to background noise and the talker is located in front of the CI user, then switching to a beamforming program will be appropriate. In contrast, for speech in quiet, the everyday program with omnidirectional microphone characteristic should be selected. In reality however, very few users change programs from their everyday settings and are often not used to seeking out noisy situations, but avoiding them The study showed that already the adaptive beamformer implemented in the Ambra hearing aid in conjunction with a Harmony speech processor produced a substantial improvement of 5.2 dB in SRT in a challenging noise setting with speech weighted noise compared to the omni-directional microphone. The binaural beamformer even produced SRT improvements of 7.1 dB over the omni-directional microphone. An overall trend towards better performance with CV was observed. Improvements of CV were likely limited in this particular study group, at least in parts, by the adaptive test methodology and the very good SRTs obtained, even without beamformer. The challenging test set up with noise sources also in the frontal hemisphere, aimed to produce a more realistic scenario compared to other studies, where noise was presented from one single speaker or within the rear hemisphere only. Even though the gain of the single-sided adaptive beamformer was remarkable, the results demonstrate that the potential performance benefits of a four-microphone binaural beamformer in challenging hearing situations are still large.


Hearing impairment at the workplace, and the resulting psychosocial problems are a major health problem with substantial costs for employees, companies, and society. Therefore, it is important to develop interventions to support hearing impaired employees. The objective of this article is to describe the design of a randomized controlled trial evaluating the (cost-) effectiveness of a Vocational Enablement Protocol (VEP) compared with usual care.Participants will be selected with the 'Hearing and Distress Screener'. The study population will consist of 160 hearing impaired employees. The VEP intervention group will be compared with usual care. The VEP integrated care programme consists of a multidisciplinary assessment of auditory function, work demands, and personal characteristics. The goal of the intervention is to facilitate participation in work. The primary outcome measure of the study is 'need for recovery after work'. Secondary outcome measures are coping with hearing impairment, distress, self-efficacy, psychosocial workload, job control, general health status, sick leave, work productivity, and health care use. Outcome measures will be assessed by questionnaires at baseline, and 3, 6, 9, and 12 months after baseline. The economic evaluation will be performed from both a societal and a company perspective. A process evaluation will also be performed.Interventions addressing occupational difficulties of hearing impaired employees are rare but highly needed. If the VEP integrated care programme proves to be (cost-) effective, the intervention can have an impact on the well-being of hearing impaired employees, and thereby, on the costs for the company as well for the society.NTR2782Netherlands Trial Register (NTR):  Hearing impairment is a common chronic condition in The Netherlands and worldwide. Although the vast majority of adults with hearing impairment has already retired , there iSo far, only a few studies have addressed the impact of hearing impairment on work performance. The studies that have been revealed that there is a range of concerns and problems that hearing impaired employees are likely to experience. Most frequently reported issues are lack of control, problematic functioning in environmental noise, concerns about job safety, sick leave, and the fear to loose employment -8. FurthHearing impairment has consequences not only for the working hearing impaired individuals themselves, but also for companies and society. Previous studies showed that hearing impaired people are overrepresented in the group taking sick leave from work  and thatA search of the literature showed that interventions specifically supporting hearing impaired employees have scarcely been described. Programmes, other than those aimed at preventing noise-induced hearing loss, for example the protocol of the Dutch Board for Occupational Medicine (NVAB) , are praAn integrated care programme to facilitate and improve the working situation for hearing impaired employees was developed by Kramer et al. . The IntSatisfaction and experiences with the VEP integrated care programme is already evaluated and described elsewhere . HoweverA two-armed randomized controlled trial, with a follow-up of one year will be performed. Employees randomly allocated to the intervention group will receive the VEP integrated care programme; employees allocated to the control group will receive usual care. Measurements will take place at baseline, and 3, 6, 9, and 12 months after baseline measurement. The study design is presented as a flow diagram in Figure n < -5.5 dB), insufficient (-5.5 ≤ SRTn ≤ -2.8 dB), and poor hearing (SRTn > -2.8 dB) [The study population will be recruited from three occupational health services (OHSs) in The Netherlands. One OHS is attached to a university including a university medical hospital. The second is the OHS of an international steel industry company. The third OHS is attached to an airline company. Employees will be invited to participate during organizational periodical health screenings (PHSs) if their pure-tone audiogram shows a hearing impairment (for a definition of hearing impairment see Inclusion and exclusion criteria for the study population), or participants can present themselves after reading a flyer of the study distributed among the employees of the participating companies. Potential participants will be selected on the basis of both measured hearing impairment and the self-rated level of distress . To screen employees for eligibility on these two factors, the 'Hearing and Distress Screener' (HDS) is developed. The HDS contains five items. Table -2.8 dB) . If the Inclusion criteria1. Diagnosis of hearing impairment  or a score of 'insufficient' or 'poor' on the National Hearing test3. A score of ≥ 7 on the 'Hearing and Distress Screener'4. Age above 18 year5. Paid work for at least 8 hours a week6. Able to complete questionnaires in Dutch7. Available for the study for the following 12 monthsExclusion criteria1. Tinnitus is the primary condition affecting the individual2. Already referred to or received the VEP integrated care programme during the past 12 months3. Not willing or unable to comply with the VEP integrated care programme4. Employee is pregnantEmployees with a score of 7 or more on the HDS and who indicate to be willing to participate, will be contacted by the researcher by e-mail or telephone. During this contact, the researcher provides information about the implications of participation in the study and sends written information to the employee's home. The researcher then plans a face-to-face appointment with the employee about one week after having sent the written information. During this appointment the inclusion and exclusion criteria will be checked (Inclusion and exclusion criteria for the study population), informed consent will be obtained and the baseline questionnaire will be completed. At the end of the appointment the employee will be randomized to the intervention or control group.All eligible participants will be randomly assigned to the intervention or the control group after the baseline measurements. To prevent an unequal distribution among groups, employees will be pre-stratified on two prognostic factors before randomization. The first one is requirement of hearing protection at the workplace. The second prognostic factor is psychosocial related problems based on the HDS (score of 3 or more on the three distress items (items 1 to 3) of the HDS). This results in a total of four strata. Furthermore, block randomization, with blocks of four, will be applied to ensure equal groups sizes within each stratum and for practical reasons. An independent statistician will prepare the randomization schedule by using computer-generated random numbers. The research assistant will arrange sealed envelopes before the start of the study containing either a referral to the intervention group or to the control group. When the baseline questionnaire is completed, the employee can choose an envelope in the correct stratum that contains the randomization under the researcher's supervision.'Need for recovery after work' is the primary outcome of this study and was therefore used for the power calculation. The 'need for recovery after work' scale comprises 11 dichotomized items . Based oDue to the nature of the intervention, it will not be possible to blind the participants, the multidisciplinary team of the VEP integrated care programme, or the OPs of the companies to treatment allocation. After randomization, all participants will receive a non traceable research code consisting of consecutive numbers. A research assistant will enter all data into the computer using these research codes. Thus, the researcher who will analyse the data will be blinded.Co-interventions cannot be avoided. Information about all treatments and co-interventions received by the participants will be collected by means of questionnaires on health care use in both the intervention and the control group. In the intervention group, the compliance with the recommendations and advices of the VEP integrated care programme will be measured by asking employees which intervention components they received. These recommendations and advices will be compared with the delivered recommendations and advices by the professionals.The participants in the intervention group will be referred to the Audiological Clinic of the VU University Medical Center and receive the VEP integrated care programme.The VEP integrated care programme comprises an assessment of auditory function, work demands and personal characteristics by a multidisciplinary team comprising an audiologist, OP, social worker, and psychologist. The VEP integrated care programme is extensively described elsewhere  and brieAs soon as an employee is assigned to the VEP integrated care programme, a work-related questionnaire is sent to the employee's home. The employee is asked to fill in the questionnaire and bring it to their consultation at the audiological clinic. This questionnaire assesses the type of work, the work environment, and activities, including hearing activities at work .In the clinic, the hearing status of the employee is measured using auditory tests. Next to regular pure-tone and speech audiometry, SRT tests (presented in quiet and against a background of steady state noise and fluctuating noise) ,29 are pDuring a semi-structured interview performed by the psychologist or social worker, the psychosocial status of the employee, and his/her specific needs, attitudes towards hearing loss, work and work-related problems are evaluated. This interview is also attended by the OP of the team to evaluate the (person's perspective on) work-related problems. After the tests and interview, the results are examined and considered by the multidisciplinary team consisting of the psychologist or social worker, the OP, and the audiologist in order to establish an interdisciplinary profile of audiological, personal and occupational characteristics. In a multidisciplinary team meeting, all findings are discussed. A written report is then compiled. This report includes recommendations for the employee and covers a proposed management plan which is discussed by telephone with the OP on site. The request of the OP on site is to supervise the implementation of the recommendations and advices. The participant's general practitioner receives a copy of the written report. Finally, the results and conclusion are discussed with the employee. Possibilities of technical, speech-therapeutic and/or psychosocial interventions are then considered. If indicated, the workplace itself is visited in order to inspect acoustical and occupational circumstances. A schematic figure of the VEP integrated care programme is presented in Figure Participants in the control group will receive usual care, based on advices of their own OP. The OP can refer the employee to the general practitioner, ENT specialist, or to an audiological clinic for further audiological diagnostics and care for hearing impaired persons with work-related difficulties. Furthermore, participant with noise-induced hearing loss will receive care based on existing guidance . TreatmeOutcome measures will be collected either by online questionnaire or via paper-and-pencil copies. The hard copy questionnaires, including reply paid envelopes, will be sent by regular post to participants without access to or who do not use Internet. Data will be collected at baseline and after 3, 6, 9, and 12 months after baseline measurement. To reduce loss to follow-up, reminders will be sent by e-mail or regular post (paper-and-pencil users) to ask participants to complete the questionnaires with a maximum of three reminders. If they do not wish to further participate in the study, the reasons for their withdrawal will be recorded.Primary outcome is defined as the 'Need for Recovery (NFR) after work' . This isThe Communication Profile for the Hearing Impaired (CPHI) ,34 assesDistress is measured by the distress scale of the 4DSQ . This scThe EuroQol EQ-5D  will be The General Self-Efficacy Scale (GSES)  measuresThe behavioural determinants attitude, social influence and self-efficacy (ASE) can provide insight into (the intention to perform) the desired behaviour. Questions about attitude, social influence, and self-efficacy for hearing impaired employees are formulated based on questions often used in health promotion research ,41. Six Self reported sick leave days are determined over the past three months using the PROductivity and DISease Questionnaire (PRODISQ). The questions cover relevant aspects of sick leave including compensation mechanisms that may reduce productivity losses at work . AdditioHealth care use is measured using a modified version Tic-P questionnaire . The numPsychosocial workload is considered to be a potentially prognostic factor for the primary outcome measure, 'need for recovery after work'. A validated Dutch version of the Job Content Questionnaire (JCQ)  will be For an overview of the outcome measures and measurement moments see Table A bottom-up cost price calculation will be performed to calculate costs of the intervention and control group. Total costs consisted f costs for the intervention, costs for productivity loss, costs for sick leave, and health care costs. The intervention costs include costs for the implementation of the intervention . Costs for productivity loss are costs due to sick leave and costs due to reduced self-reported work productivity. These costs will be calculated according to the human capital cost approach and the friction cost approach, based on income as provided by the employee or as derived from age- and sex-specific income of the Dutch population . The humHealth care costs include costs of the visits to health care providers, diagnostic examinations, and medication due to health problems . The health care costs will be evaluated according to the prices suggested in the guidelines for economic evaluation in The Netherlands . If costAll analyses will be performed according to the intention-to-treat principle. Baseline characteristics of employees in the two groups will be compared using descriptive statistics. Linear and logistic regression will be performed. Furthermore, analyses at the level of the OHSs are performed by the use of multilevel analysis. To assess whether protocol deviations cause bias, the results of the intention-to-treat analyses will be compared to per-protocol analyses, from which employees who are not treated according to the procedure of the intervention. For all analyses, a two-tailed significance level of < 0.05 is considered statistically significant. Linear and logistic regression analyses will be performed with SPSS 18.0 . The multilevel statistical analyses are performed with MIWin 2.0.In the economic evaluation the costs and consequences of the VEP integrated care programme and usual care will be compared. As mentioned in the introduction, hearing impairment has consequences with potentially substantial costs for the companies, as well for the society. Since interventions in occupational care in The Netherlands have to be paid by employers, the economic evaluation will be conducted from both a company and a societal perspective. From the societal perspective, all costs and consequences of the intervention will be taken into account regardless of who pays for them. From the company perspective, only costs due to the intervention, productivity, and sick leave will be taken into account.Missing data will be imputed using a multiple imputation procedure according to the multivariate imputation by chained equations (MICE) method ,51. To cAdditional to the effect evaluation and the economic evaluation, the process of the VEP integrated care programme will be evaluated. Two models for process evaluation will be combined, namely the model of Steckler and Linnan  and the Hearing impairment at the workplace has consequences for the hearing impaired individual, the company, and society ,7. So faThe VEP integrated care programme is unique because usual care often does not include adequate interdisciplinary diagnostics and audiological rehabilitation procedure other than hearing aid fitting for addressing the problems related to hearing impairment in the workplace. In particular the psychosocial problems are often left behind and protocols for improvement of the workplace by applying accommodations for the hearing impaired employee are not broadly implemented.Results of this study will be analysed within the context of the ICF classification. From the perspective of the society and employer the study will evaluate the components of the health condition  such as activities, participation and environmental and personal factors, namely with questionnaires about work demands, 'need for recovery after work', and general health status. In this article the design of a study to investigate the effectiveness, cost-effectiveness, and feasibility of the VEP integrated care programme for hearing impaired employees is described.A strength of the current study is the randomized design. Another strength is that not only the effects of the VEP integrated care programme will be evaluated, but also the cost-effectiveness and the process of the programme. Finally, in this study presenteeism is measured. This is important, because even if an employee is not absent from work, hearing impairment can cause a reduction of work productivity .Hearing impairment is not a disorder that is visible and it usually develops gradually. Hence, it is often not recognized or considered to be a problem by employees. Many people perceive their hearing impairment as part of themselves and are therefore not alarmed by it. The employees who do recognize the problem of their hearing impairment may not report it, because of shame or the fear for stigma . It may This VEP integrated care programme is a promising way to help reducing work disability and the burden for hearing impaired employees. If this study will prove its effectiveness, the VEP integrated care programme can foster the maintenance, and improvement in the well-being of employees with hearing impairment by facilitating and retention of their work through the VEP broadly. When proven cost-effective from the company perspective, it can be considered as a useful intervention in other occupational health care settings to prevent disabilities for hearing impaired employees. Furthermore, if cost-effective from the societal perspective, it will be worth considering inclusion of the VEP integrated programme in the basic package of social insurances. It is expected that the results of this study will become available in 2014.ASE: attitude, social influence and self-efficacy; BCA: bias corrected and accelerated bootstrapping; CE: cost-effectiveness; CEAC: cost-effectiveness acceptability curves; CPHI: communication profile for the hearing impaired questionnaire; dB: decibel; dB SNR: decibel signal-to-noise ratio; EMP: employer; ENT: ear nose and throat; GP: general practitioner; GSES: general self-efficacy scale; HDS: hearing and distress screener; ICER: incremental cost-effectiveness ratio; ICF: international classification of functioning: disability and health; JCQ: job content questionnaire; JDC: job demand control; MICE: multivariate imputation by chained equations method; NFR: need for recovery; NVAB: Dutch board for occupational medicine; OHS: occupational health services; OP: occupational physician; PHS: periodical health screening; PRODISQ: productivity and disease questionnaire; PSQOH: patient satisfaction with occupational health services questionnaire; SNR: signal to noise ratio; SRT: speech reception threshold; VAS: visual analogue scale; VEP: vocational enablement protocol; WHO: World Health Organization; 4DSQ: four dimensional symptom questionnaire.SEK and STG are each involved both as researcher and as clinician in this study. They are the psychologist and the audiologist of the multidisciplinary team of the VEP integrated care programme respectively.AHMG is responsible for the data collection and drafted the manuscript. SEK and JRA are the guarantors of the study. SEK and STG designed the intervention programme. AHMG, SEK and JRA developed the study design. JRA is responsible for the recruitment of companies participating in the study. STG is responsible for the VEP integrated care programme in the clinic. SEK, JRA, JB, STG and JMF gave critical comments on the draft manuscript and had a role in supervision. All authors participated in discussing the design of the study and read and approved the final manuscript.The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1471-2458/12/151/prepub


Borrelia burgdorferi, the spirochete that causes Lyme disease, differentially regulates synthesis of the outer membrane lipoprotein OspC to infect its host. OspC is required to establish infection but then repressed in the mammal to avoid clearance by the adaptive immune response. Inverted repeats (IR) upstream of the promoter have been implicated as an operator to regulate ospC expression. We molecularly dissected the distal inverted repeat (dIR) of the ospC operator by site-directed mutagenesis at its endogenous location on the circular plasmid cp26. We found that disrupting the dIR but maintaining the proximal IR prevented induction of OspC synthesis by DNA supercoiling, temperature, and pH. Moreover, the base-pairing potential of the two halves of the dIR was more important than the nucleotide sequence in controlling OspC levels. These results describe a cis-acting element essential for the expression of the virulence factor OspC. Borrelia burgdorferi, which is transmitted via an Ixodes tick B. burgdorferi is maintained in an enzootic cycle between its tick vector and a vertebrate host reservoir B. burgdorferi when feeding on an infected animal and can then transmit the bacterium to uninfected hosts as nymphs during feeding, completing the cycle. B. burgdorferi encounters disparate, and hostile, environments as it transitions through the enzootic cycle; the spirochete has evolved a repertoire of strategies, which involve the regulation of a variety of genes, to respond and adapt to these changes during its lifecycle Lyme disease is caused by the spirochete B. burgdorferi and its hosts, is paramount to the ability to infect, survive and replicate in both the tick and the vertebrate ospC gene is carried on the conserved 26-kb circular plasmid cp26 B. burgdorferi that continue to produce OspC during infection of immunocompetent mice are cleared ospC expressed in trans from a shuttle vector is selected against during mammalian infection ospC is present in all B. burgdorferi strains examined, the sequence is variable, with only strains carrying certain alleles capable of disseminating and establishing infection in humans The differential syntheses of outer surface lipoproteins (Osp), which are the interface between in vitro in response to increased temperature, which presumably mimics a signal that occurs during tick feeding ospC expression. External signals are transmitted through a unique signaling pathway involving the sequential action of two alternative sigma factors, RpoN (σ54) and RpoS (σs) rpoS; RpoS, in turn, activates transcription of ospCospC expression is exerted during translation of rpoS. The small RNA DsrABbrpoS translation and subsequently ospC transcription. However, there is no evidence for post-transcriptional control of the ospC gene OspC synthesis is induced ospC operator consisting of two overlapping inverted repeats (IRs) 42 bp upstream of the major transcriptional start site B. burgdorferi sensu stricto ospC gene regulation. Eggers et al. ospC expression in vitro, while Yang et al. ospC expression during infection ospC was expressed in trans in an ospC null background strain. In the current study, we molecularly dissect the ospC operator in its native locus on cp26 and show that the distal IR is an important cis-acting element controlling OspC expression.Previous studies identified an B. burgdorferi strain 297 (BbAH130) 5 cells ml−1 and growing at 23°C to late log phase (5 to 9×107 cells ml−1) or inoculating cultures at 1×103 cells ml−1 and growing at 34°C to late log phase. For temperature downshift experiments, cultures were grown to log phase at 34°C before inoculating cultures at 1×105 cells ml−1 and growing at 23°C to late log phase. In experiments examining the effect of pH, cultures at 34°C in BSK II at pH 8.0 were passaged into BSK II at pH 7.0. To determine the effect of DNA supercoiling, cultures were grown at 23°C (inoculated at 1×105 cells ml−1) in the presence of 10 ng ml−1 coumermycin A1 (50 mg ml−1 stock in DMSO) or DMSO (solvent control) until late log phase Low-passage ospC operator were generated by allelic exchange on cp26 ospC gene, was amplified by PCR using the primers ospC D697R+AatII+AgeI and ospCp mutHup(297)F . The plasmid was linearized by digestion with AhdI and electroporated into competent B. burgdorferi −1) at 34°C and a 1.5% CO2 atmosphere ospC operator mutations.Mutations in the up(297)F . PCR proup(297)F  were addup(297)F  was usedB. burgdorferi grown at 23°C containing 10 ng ml−1 coumermycin A1 or DMSO as a solvent control using TRIzol (Invitrogen) as previously described ® III for qRT-PCR (Invitrogen). flaB and ospC primers and probes were designed using Primer Express® version 3.0 (Applied Biosystems). TaqMan absolute qRT-PCR was performed in 96-well plates using an Applied Biosystems 7300 Real-Time PCR System and standard curves for flaB and ospC were generated using a portion of the flaB ORF (nucleotides 278–551 of the ORF) cloned into pCR®2.1-TOPO and B. burgdorferi strain 297 (BbAH130) genomic DNA, respectively. Values represent the mean (±SE) from three independent experiments.RNA was isolated from 40-ml cultures of B. burgdorferi cultures were grown to late log phase at 23°C or 34°C and total cell lysates collected as previously described 2HPO4, 1.5 mM KH2PO4, 0.05% Tween 20, 4% dry milk, and 1% goat serum) overnight at 4°C. Membranes were incubated with rabbit anti-OspC antibodies (1∶1000) http://rsbweb.nih.gov/ij/) and Pixelmator .ospC operator consists of a set of overlapping inverted repeats that are highly conserved in B. burgdorferi sensu stricto strains  and that changed the dIR sequence but retained complementarity (dIR+)  until late log phase to examine if the increase in ospC expression by the relaxation of supercoiling is mediated by the dIR of the operator. Transcript levels of ospC and flaB were measured by qRT-PCR. The fold increase in ospC transcript in the dIR+ strain grown in coumermycin A1, compared to the solvent control, was significantly greater than that seen in the dIR− strain (about thirteenfold compared to less than twofold) (flaB transcript levels was about twofold or less for both the dIR+ and dIR− strains (1-mediated ospC expression.We have previously shown that a decrease in negative DNA supercoiling causes an increase in twofold) . The cha strains . These dospC transcript levels in response to coumermycin A1 treatment were reflected in OspC protein levels, total cell lysates were analyzed by Western blot using polyclonal antibodies to OspC to determine the levels of OspC synthesis. OspC levels increased in the wild-type 297 strain in response to relaxation of supercoiling when grown at 23°C in the presence of coumermycin A1 compared to cultures grown in the DMSO control , albeit still circular, with a strong promoter fused to a selectable marker, may affect operator function, especially when DNA topology is likely involved trans were elevated at 23°C compared to wild type, even though the plasmid-borne ospC contained the entire operator region The large intergenic region upstream of the − strain) prevent an increase in OspC levels in response to temperature, pH or relaxation of supercoiling, suggesting that all these signals function through a similar mechanism. Thus, the dIR is required for an increase in the amount of OspC. The finding that the ospC induction by relaxation of supercoiling at 23°C with coumermycin A1 (+ strain that are important in regulation. We propose that the inverted repeats mediate the effect of DNA supercoiling, possibly by extruding a cruciform, or bind a trans-acting factor that recognizes an alternative DNA secondary structure. This provides a molecular mechanism for our previous observation that relaxation of supercoiling induces ospC expression Mutations that disrupt the dIR, but maintain the pIR (dIRmycin A1  depends cis into the genome of B. burgdorferitrans, albeit the methodology is considerably more convenient. Our results add another level of complexity to ospC regulation suggesting that the DNA structure of the operator serves to mediate the external signals affecting expression.Finally, we are aware of only a handful of studies in which site-directed mutations were introduced in


Rhinopithecus roxellana) inhabiting the Qinling Mountains of central China. R. roxellana exhibit a multilevel social organization characterized by over 100 troop members organized into 6–11 one-male units each composed one adult male and several adult females and their offspring. Behavioral data were collected over the course of 28 months on grooming patterns between mothers with infants less than 6 months old (N = 36) and other adult female troop members. Our results provide strong evidence for the interchange of grooming for access to infants. Grooming for infant access was more likely to be initiated by potential handlers (nonmothers) and less likely reciprocated by mothers. Moreover, grooming bout duration was inversely related to the number of infants per female present in each one-male unit indicating the possibility of a supply and demand market effect. The rank difference between mothers and handlers was negatively correlated with grooming duration. With increasing infant age, the duration of grooming provided by handlers was shorter suggesting that the ‘value’ of older infants had decreased. Finally, frequent grooming partners were allowed to handle and maintain access to infants longer than infrequent groomers. These results support the contention that grooming and infant handling may be traded in R. roxellana and that the price individuals paid for access to infants fluctuated with supply and demand.According to a biological market paradigm, trading decisions between partners will be influenced by the current ‘exchange rate’ of commodities (good and services), which is affected by supply and demand, and the trader’s ability to outbid competitors. In several species of nonhuman primates, newborn infants are attractive to female group members and may become a desired commodity that can be traded for grooming within a biological market place. We investigated whether grooming was interchanged for infant handling in female golden snub-nosed monkeys ( Biological market theory Grooming, is the most common affiliative behavior engaged in by nonhuman primates Previous research has demonstrated that primate ‘reciprocal traders’ commonly exchange or reciprocate grooming for grooming Papio hamadryas ursinus) these authors found that mothers were groomed for longer periods of time when there were fewer newborns in the group, a finding confirmed in several primate studies Rhinopithecus roxellana). Observations of this species indicate that females without infants are attracted to females with young infants and groom them frequently In several species of primates, newborn infants are very attractive to group members, especially females, and mothers with young infants receive high levels of social attention Rhinopithecus roxellana) is a rare and endangered colobine primate endemic to China. Colobines are foregut fermenters and possess adaptations of their stomach  that enable them to exploit a diet composed primarily of leaves, lichen, seeds, and other difficult to digest plant material R. roxellana is characterized by a multi-level society R. roxellana is a strictly seasonal breeder The golden snub-nosed monkey , China, where the study took place, and to the American Society of Primatologists principles for the ethical treatment of primates. This research received clearance from and complied with the protocols approved by animal care committees of the Wildlife Protection Society of Shaanxi Province, China (permit number: SX43537ACC). Legal permission to conduct this research also was provided by ZNNR.2 of temperate forest and is characterized by a semi-humid montane climate. Elevation ranges from 1,400 to 2,890 m above sea level. The composition of the forest varies with altitude, from deciduous broad-leaf forest at low elevations to mixed coniferous broad-leaf forest above 2,200 m, to coniferous forest above 2,600 m The study site is located in the Yuhuangmiao region of Zhouzhi National Nature Reserve on the northern slopes of the Qinling Mountains, in Shaanxi province, China . The ZNNR was established in 1985 to protect 52,931 kmTwo polygynous groups of golden snub-nosed monkeys are present ZNNR, the east ridge troop (ERT) and the west ridge troop (WRT). The WRT was chosen as the study troop and is characterized by a multi-level social structure consisting of one to two all-male bands and 6–11one-male units (OMU). Details of the study troop have been reported previously Data presented in this study are based on 1,956 hr of behavioral observations collected from March 2009 to 2011 July. Given that individuals of the same one-male unit, especially females, usually remain in close spatial proximity, we were able observe all resident adult OMU females simultaneously. Continuous focal animal behavioral sampling During the study period, 26 females in 6 OMUs gave birth. One of these females lost her infant a few days after birth, probably due to natural causes. Ten of these females gave birth both in 2009 and 2011. Five of the 26 females were primiparous and the remaining 21 females were multiparous. Infants under the age of 6 months were selected for study. Infants of this age class possess a distinctive natal coat and are the most attractive to other animals. In total we observed 36 infants during the study period.Given that we have been observing this troop for over a decade, maternal kinship and non-kin relationships are known for all group members. Approaches were scored when potential handlers or mothers moved to within one arm’s length of the infant. We also recorded the time and social context during periods when handlers or mothers approached or moved away from the infant. A grooming bout was defined as a continuous period of allogrooming lasting at least 10 seconds. A groom bout was scored as ending when either the direction of grooming changed (A groomed B became B groomed A) or when there was a cessation in grooming of more than 60 s. A grooming session is a series of bouts of grooming in either direction between two individuals that was not interrupted for more than 10 min. Infant-handling behaviors recorded included visual inspection, nuzzle, hold, carry, nurse, cradle, groom, and touch .t-test to analyze whether females’ were approached more frequently and groomed for longer periods after giving birth than before parturition. The Paired sample t-test also was used to analyze whether there was a difference between the proportion of grooming mothers’ received and the proportion of grooming mothers gave on each day. We used a binomial test to determine whether grooming sessions were more likely to be initiated by nonmothers. A G test was used to compare the proportion of reciprocal grooming sessions in mother-nonmother dyads and nonmother –nonmother dyads. Grooming sessions directly linked to sexual interactions were excluded. A Wilcoxon signed-ranks test was conducted to analyze whether potential handlers preferentially selected mothers as grooming partners. The observed proportion of grooming episodes received by mothers from potential handlers for each day was compared with the proportion of grooming episodes mothers were expected to receive in relation to their availability (N = 197 data collection day).To evaluate the effects that the presence of an infant had on female-female social interactions, we calculated hourly rates of approaches and the proportion of time a female received or gave grooming 5 months before and 6 months after giving birth. Two-way repeated measures ANOVAs were used to examine whether there were differences in the rate of approaches or frequency of grooming related to maternal status (mother vs. nonmother) and direction of behavior (given and received ). Individual data were compared using the Paired sample N = 897). A G test was used to investigate whether handlers in mother–mother dyads were significantly more likely to obtain access to infants without first grooming the mother compared to handlers in mother– nonmother dyads.We used multilevel mixed-effects logistic regressions to determine whether grooming by handlers affect maternal responses to attempts by handlers to interact with infants. Maternal responses were recorded as ‘positive’ when mother allowed a handler to interact with her infant or ‘negative’ when mother left the area or moved her infant away from an approaching handler. Maternal responses were entered as dependent variables and grooming given by potential handlers, the age of the infant (months) at the time the grooming bout was observed, rank difference between potential handler and mother, the current number of newborn infants (≤6 months) per female in each one-male unit were included as independent fixed effect variables. Grooming given by, potential handlers was tested either as a categorical (yes/no occurrence) variable. Data points here were all dyadic interactions between mothers and potential handlers in which the individuals from the initial approach to the final leaving of either the mother or the potential handler in observation (N = 756). Grooming data were standardized by subtracting the mean and dividing by the standard deviation to show whether the duration of grooming in each OMU fluctuated with the number of infants present during each of the three different birth seasons. The mean grooming time for each OMU was transformed by subtracting mean grooming bout length from the length of each grooming bout and dividing by the standard deviation in each of the 3 birth seasons over which this study was conducted. A multilevel mixed-effects linear regression was also used to investigate whether high-ranking potential handlers were better able to get access to younger or relatively less infants. The rank difference between the mother and the handler were entered as the dependent variable, and age of infants and the number of infants per female were included as independent fixed-effect variables. The identity of handlers and mothers were inserted as random effects, crossed with each other and nested in the OMU identity. Data points were the number of that the handlers got accessing to infants from mothers (N = 781). To test whether predictions 5 and 6 were supported (impact of grooming time and rank difference on infant handling time), we also used multilevel mixed-effects linear regressions. The duration of infant handling (s) were defined as the dependent variable. Fixed effects included the duration of the handler’s grooming bout, the current number of infants (≤6 months) per female in each OMU, the age of the infant when the grooming bout occurred, and the rank difference between the mother and the handler. The results showed that rank difference did not have a significant effect on handling time. However, we noted that certain females in each OMU were permitted to handle infants for longer periods of time when rank difference interacted with infant’s age and the number of infants presented in an OMU. In addition, previous analyses performed on grooming sessions outside birth and mating seasons revealed that even if females had as many as five partners to select from, most grooming occurred between two closely ranked females who interacted as frequent groomers N = 756). Data were analyzed using the SAS 9.2 statistical package.To investigate whether the predictions 3–5 (factors affecting the grooming time nonmothers invested in mothers) were supported, multilevel mixed-effects linear regressions was used which examines each of the fixed effects. The duration of grooming (s) given by handlers was used as the dependent variable. For each grooming point, fixed effects consisted of the current number of newborn infants (≤6 months) per female in each one-male unit, the age of the infant (months) when the grooming bout was observed, and the rank difference between the mother and the handler. The position of females in their OMU dominance hierarchy was determined based on the outcome of decided agonistic events between females F1,70 = 23.17, p<0.05; t test: t35 = −10.01, p<0.05) compared to the 5 months prior to giving birth . In contrast, nonmothers were approached less frequently than mothers , and the rate of approaches among nonmother-nonmother dyads decreased during the birth season compared to the period prior to infant births . During the 6 month period after mothers’ gave birth, the rate nonmothers approached mothers was significantly higher than the rate at which they approached nonmothers .The presence of infants significantly influenced the rate at which handlers approached mothers. We found that the rate at which mothers or nonmothers were approached differed significantly . A total of 756 grooming-infant handling interchanges were recorded between mothers and nonmothers. Of these, 89.3% were initiated by potential handlers and only 10.7% initiated by mothers. We found that grooming sessions were more likely to be initiated by nonmothers  and less likely to be reciprocated by mothers (G1 = 901.73 p<0.001). Mothers were chosen as grooming partners significantly more than expected based on their relative presence within their OMU . An analysis of grooming sessions indicated that 83% were unidirectional and mothers reciprocated grooming on only 17% of occasions. In contrast, 91.7% of the total 673 grooming session between nonmother dyads were bidirectional and nonmothers commonly reciprocated by grooming their partners. The average duration of grooming bouts in which nonmothers groomed mothers was 241.4±292.8 s (mean ± SD). Mothers were groomed by nonmothers for a longer duration after they gave birth (241.4±292.8 s) than before parturition (197.1±121.7 s) . However the proportion of time mothers spent grooming others decreased across these two periods  while the proportion of time nonmothers spent grooming mothers increased . Similarly, the proportion of grooming mothers with young infants received from nonmothers was significantly higher than the proportion of grooming these mothers directed at nonmothers . Similarly, nonmothers groomed mothers for a significantly longer period of time than they were groomed by mothers . Finally, nonmothers groomed mothers for significantly longer periods of time than they grooming other females .Grooming also was significantly affected by the presence of infants .Whether nonmothers groomed mothers prior to handling infants has significant effect on maternal responses to attempts by nonmothers to interact with infants. Grooming by nonmothers prior to handling infants increased the probability of nonmothers accessing to the infants  and decrt257 = −18.94, p<0.001). Handlers in mother–mother dyads were significantly more likely to obtain access to infants without first grooming the mother than were handlers in mother– nonmother dyads .We recorded only 29 cases infant handling that occurred across mother-mother dyads. The duration of mother-mother grooming was shorter (112.2±79.3 s vs. 241.4±292.8 s) than nonmother-mother grooming . The higher ranking the handler was compared to the mother, the less time was invested in grooming the mother. The greater the rank difference between a lower ranked female and a mother, the greater the duration of time that female groomed the mother in order to obtain access to her infant. In addition, the rank difference between nonmothers and mothers was significantly related to the age of the infant . When infants were young, mothers and handlers were closely ranked or handlers were of higher rank than mothers, supporting the notion that access to young infants was a valued commodity sought after by nonmothers. However, nonmothers of lower rank than mothers were not excluded from getting access to infants when the number of infants per female was relatively low in the OMUs .The number of infants per female, age of infants, and rank difference had a significant impact on the amount of time nonmothers invested in grooming mothers. Grooming duration increased significantly when the number of available infants per female in each OMU decreased . Grooming times only had a significant influence on infant handling time when controlling for the number of infants per female in each OMU . Nonmothers who groomed mothers longer increased their access to infants only when infant availability also increased. Frequent female grooming partners significantly affected the infant handling duration . Frequent groomers were allowed to handle infants significantly longer than infrequent grooming partners and the duration of infant handling decreased significantly when females were not frequent groomers. The duration of infant handling was not significantly affected by the infant age .The number of infants per female significantly predicted the duration of infant handling. The duration of infant handling decreased significantly when the number of available infants increased . Females received more approaches and were groomed for longer periods of time in the months following the birth of their infant than in the months prior to parturition. Females without infants (nonmothers) were strongly attracted to newborn infants and preferentially groomed mothers as a social tool to obtain access to their infants. Nonmothers were found to groom mothers more frequently and for a greater duration than mothers groomed them in return. Previous research on R. roxellana R. roxellana OMU. These results support the biological market prediction that the scarcity of a resource or a service increases its value, while the increased availability of that resource or service decreases its value The results of this study indicate that the presence of newborn infants has a significant effect on the dynamics of adult female social interactions in wild golden snub-nosed monkeys  and marmosets  We also found an effect of female rank on patterns of grooming associated with access to infants. In golden snub-nosed monkeys, rank appears to shift the balance for many individuals from dyadic interactions based on reciprocity to dyadic interactions that are characterized by the unequal exchange of the same service or the interchange of differences services. For example, lower-ranked females groomed higher-ranked mothers for longer duration than vice versa. On average higher-ranking females grooming lower ranking mothers for 213.7±171.3 seconds (mean ± SD) whereas lower-ranking females groom higher ranking mothers an average of 261.2±234.1 seconds in order to obtain access to their infants (Prediction 5 partly supported). This suggests that lower-ranked and higher-ranked females are characterized by different social strategies and these change with infant attractiveness. Higher-ranked nonmothers were able to ‘pay a lower price’ than the one set by the current supply/demand ratio or paid back in a different ‘currency’, e.g. tolerance at food sources or support in conflicts. When infants were very young, handlers were more likely to be closely ranked or of higher rank than the infant’s mother. However, this pattern did not continue once infants reached 6 months of age. This suggests that when infants were most highly valued, higher-ranked nonmothers successfully outbid lower-ranked competitors for infant access. As these infants aged, however, their ‘value’ appeared to decrease and lower-ranked handlers had greater access to infants by increasing the time they invested in grooming higher-ranking mothers. If access to higher-ranked mothers and their infants are of greater value in the biological market place than access to lower-ranked females and their infants, then the primary goal of lower ranking females may have been to use access to infants as a means of developing a social relationship with a female of higher rank. These same low-ranking females could gain equal infant caregiving experience at a lower cost (reduced time grooming) by preferentially grooming mothers of low social rank. In contrast, it is likely that higher ranked females who groom lower ranking mothers do so for the primary purpose of obtaining infant caregiving experience, as social bonds or alliances with these low ranking mothers offer limited benefits. This may be analogous to data obtained in studies of captive female tamarins  offer advantages in fitness .Finally, several previous studies R. roxellana access to infants represents a commodity that can be traded for grooming. The ‘value’ of infant handling varied based on supply and demand, the social status of the individual traders, and whether potential handlers had a long-term relationship with the infant’s mother. Given that golden snub-nosed monkeys are strictly seasonal breeders, more than one similarly aged infant is commonly present in an OMU. Nevertheless nonmothers from one OMU do not groom mothers from neighboring OMUs or interact with their infants. Therefore, the availability of infants in a female’s resident OMU has a strong impact on female social interactions. The presence of young infants appears to have a direct influence on female partner choice, grooming patterns, and the formation of long-term alliances. Mother’s with newly born infants were groomed for a longer period of time than nonmothers or mothers with older offspring. Differences in the amount of grooming females traded for access to another female’s infant appeared to be based on market ‘rules’ of supply and demand as well as female rank. Although in the case of higher ranking females, reciprocity or long-term alliances may help explain the value or costs of exchanging goods and serves, for many other females directly responding to the current value of goods and services may reduce the need for complex calculations, cost-benefit analyses or bookkeeping. We plan to continue our research on social interactions and interchange trading in golden snub-nosed monkeys in order to better identify how individuals adjust their social behavior in the face of short-term changes in the value of goods and services.Our results suggest that in