A STEP-WISE APPROACH TO FIND A VALID AND FEASIBLE METHOD TO DETECT NON-ADHERENCE TO TUBERCULOSIS DRUGS

Abstract. A step-wise approach to identify valid and feasible methods to detect non-adherence to tuberculosis drugs was evaluated in a prospective study among pulmonary tuberculosis patients in an outpatient clinic in Indonesia. First, adherence was measured by self-reporting with the standardized Morisky questionnaire, physician assessment, pill-count, visit attendance, diary and an electronic medication event monitoring system (MEMS). Next, validity of single methods was assessed against MEMS as gold standard. Feasibility of methods was then judged by physicians in the field. Finally, when valid and feasible methods were combined, it appeared that self-reporting by a questionnaire plus physician assessment could identify all non-adherent patients. It is recommended to use a systematic approach to develop a valid and locally feasible combination of methods to detect non-adherence to TB drugs. sia, a country with the third highest TB case-load worldwide (WHO, 2006). Patients in our clinic are involved in clinical trials with TB drugs and this requires good adherence. Therefore, valid and feasible method(s) to detect non-adherence are needed both for the clinical and research setting. Numerous direct and indirect methods for measuring patient adherence are now avail-able (Farmer, 1999). All these methods have specific advantages and disadvantages, for which reason a combination of methods is recommended for monitoring adherence (Farmer, 1999). In regard to the validity of these methods, many consider electronic monitor-ing using MEMS (Medication Event Monitor-ing System) as the reference or gold stan