 1900 bedded public sector hospital located in center of Karachi. Population of different socioeconomic strata caters to these hospitals. The study was conducted in 2009–2010. All hypertensive patients (an average BP of ≥140/90 mm Hg or if the participant is taking antihypertensive medications) > 18 years of age presenting to the outpatient clinics were included. Diagnosis of hypertension was confirmed by history, medical file or last prescription of any antihypertensive. Those who visited a doctor for the first time with hypertension were excluded. Patients were consecutively recruited from the outpatient setting of each hospital. Ethical approval was taken from the ethical review committee Aga Khan University (1193-Med/ERC-09). Ethical approval was also taken from Institutional Review board, Dow University of Health Sciences (IRB/DUHS/2010/40) and Ethics committee of Ziauddin University (letter 08-04-2010) Medical specialists conducting the clinic were informed about the conduct of the study. Patients fulfilling the inclusion criteria were approached and recruited by the trained research staff. Informed consent was taken from all patients before recruitment.
Study variables and measurement
Primary outcome was knowledge score which was based on 15 item questions. Knowledge was also computed as a composite measure of sum of all the 15 item questions. These questions were developed by brainstorming with experts managing hypertension and who suggested that correct response of these questions can be counted towards having sound knowledge on hypertension (in patients). Questions regarding knowledge were asked and were marked on a scale of 1–5. (Additional file1). Higher scores on a scale of 1–5 denoted more affirmative (positive) response and alluded to a better knowledge of hypertension There were some item questions which had multiple responses also. Each correct response is given a score of 1, and incorrect response is given score of 0, where there are multiple correct responses for one item question, score of 1 is give for each correct response. Sum of scores of each item question is given as total score=38. These questions were first piloted on a 20 patients (outside the study center) before using them in the study. Questions regarding adherence and physician related factors were also asked however they are not reported here. Each questionnaire took 15–20 minutes for completion.
Blood pressure was recorded twice at the time of recruitment in the right arm using a mercury sphygmomanometer with the individual in the sitting position. Average of these blood pressure readings was taken as the blood pressure reading for categorization into controlled and uncontrolled hypertension. Data was then recorded by the research staff on demographics, details on history of hypertension and antihypertensive and comorbids on a data collection form specifically designed for this purpose. (Additional file1) Ethnicity was reported as ‘mother tongue’, which is specific for each of the five major ethnic subgroups of Pakistan: Urdu speaking, Punjabi, Sindhi, Pashtu, and Balochi. Formal education was categorized based on having no formal education, < 5 years, 6–10 years and > 10 years. A history of physician-diagnosed diabetes, stroke, ischemic heart disease (IHD), chronic kidney disease (CKD) as documented in the medical records was noted. Diabetes was defined as fasting plasma glucose ≥126 mg/dl at a prior visit. Stroke was defined clinically as an acute neurologic dysfunction of vascular origin with sudden(within seconds) or at least rapid (within hours)occurrence of symptoms and signs corresponding to the involvement of focal areas in the brain. Ischemic heart disease was diagnosed using WHO definition. Smokers were defined as individuals who reported current smoking and having smoked at least 100 cigarettes or ‘birdees’ during their lifetime.
The Research staff was trained for a week to fill these data collection form. However the data collection form was not validated. Confidentiality was maintained and each data collection form was assi