patient were include in this analysis if they return a minimum of 150 day of drug data including entries of 0 pill taken. the demographic characteristics of the patient with and without a stable drug combination were compare using chi-square test fore frequency of categorical variables or independence sample t test for mean values continuous variable. unequal variance was assumed for all t test. the demographic characteristic of patient with stable drug combination who took different medication class were also compared. mean are present+ the standard deviation. SPSS version 20.0 was use for all calculation