A consecutive sampling method was used to select patients from each hospital. Data were collected every clinic day, on a selected month, in the morning from 10.00 a.m. to 12.00 noon from morning clinics, and from 2.00 p.m. to 4.00 p.m. from evening clinics until the sample size was achieved. At 10.00 a.m. the first patient available at the first dispensing counter was selected, and the next available patient in the adjacent counter at the time of completing the review of the first patient, was selected next.