To compare the changes in chronic pain prevalence and related outcomes, this study design is similar to the previous study done in our institution in 2002. The definition of chronic pain is the same as the previous study, which is pain persistence for 3 months or more. The mode of conducting the interview and the questionnaire used will be grossly similar to the previous study. Because chronic neuropathic pain is common and sometimes difficult to be managed, questions about the incidence of chronic neuropathic pain will also be sought. This important information has not been reported in Hong Kong before. The purpose of this study is to obtain the update cross-sectional prevalence and demographic information of chronic pain among Hong Kong adult population. The data will be compared with a similar study 4 done 10 years ago at our center in order to assess the change of chronic pain over the past decade. Treatment seeking preference will also be assessed. We hypothesize that the prevalence of chronic pain is increased when compare that of a decade ago.