Four measures of treatment compliance among patients recovering from psychotic episodes--a comparative study

Abstract

Patient compliance influences results of treatment of mental disorders. The study compares four measures of treatment adherence. 103 subjects were examined in the early remission from an acute psychotic (schizophrenic or schizoaffective) crisis. Compared was patient's compliance assessed by two simple scales: 5-point POP (patient's self-rating) and 7-point POK (clinician's rating) as well as by two composite questionnaires: the Drug Attitude Inventory (DAI-10) and the Medication Adherence Rating Scale (MARS). The ROC curve was used to compare sensitivity and specificity of DAI-10 and MARS scores as predictors of simple ratings. The percentage of patients who complied ranged between 42.8% to 62% (20.4-26.2% with stringent criteria applied). The POK shows a stronger correlation with the POP (0.50) than with the results of DAL-10 (0.30) or MARS (0.32). The POP correlated low with DAI-10 (0.23) and MARS (0.32). The correlation between MARS and DAI-10 was relatively high (0.67). Their reliability (Cronbach's a coefficient) only moderately exceeded the satisfactory level (DAI-10: alpha = 0.76) or approximated it (MARS: alpha = 0.61). Area under the curve (AUC) suggested comparable and significant diagnostic value of the DAI-10 and MARS. Scores extending 7.5 points indicated their optimal relation between sensitivity and specificity in predicting the clinician or patient ratings. Approximately one in two (one in four assuming the more demanding criteria) of the subjects complied with treatment recommendations. The correlation between the results of the questionnaires was relatively high, though moderate between the simple ratings. DAI-10 and MARS showed moderate reliability, sensitivity and specificity.