Development and Validation of a Tuberculosis Medication Adherence Scale

Abstract

BackgroundMedication adherence is critical in Tuberculosis (TB) treatment success, but existing tools are inadequate in identifying non-adherents, reasons for non-adherence or interventions to improve adherence. This study intended to fill the gap by developing and validating a TB medication adherence scale (TBMAS).MethodsAn initial 41-item TBMAS was designed through review of literature, consultation from an 8-member clinical expert panel and a 15-patient focus group, and pilot-testing in 25 TB patients. The questionnaire was validated in 438 patients who visited 23 community health centers for TB treatment in Wuhan from September 1, 2010, to August 31, 2011, using pharmacy refill records in a 15-week period as external criteria for medication adherence. After removing redundant and cross-loading items, the internal consistency, reliability and validity of TBMAS in identifying non-adherents were examined.ResultsThe final TBMAS included 30 items scored on a 5-point Likert scale, and these items were loaded in nine distinct factors that explained 65% of cumulative variance among respondents. Cronbach's alpha, test-retest reliability and split-half reliability were 0.87, 0.83, and 0.85, respectively. Convergent validity was supported by statistically significant associations between TBMAS scores and adherence measured by pharmacy refill records. Receiver Operating Characteristics curve analysis suggested a cut-off point at 113, with which TBMAS showed a positive predictive value of 65.5% and sensitivity of 82.9% in identifying non-adherents.ConclusionTBMAS demonstrated satisfactory internal consistency, reliability and validity in identifying TB patients with poor adherence and potential causes for non-adherence.

Psychiatric Morbidity and Other Factors Affecting Treatment Adherence in Pulmonary Tuberculosis Patients

“…Recently, a 30-item TB medication adherence scale (TBMAS) with a positive predictive value of 65.5% and a sensitivity of 82.9% was developed and incorporated the latest research in TB specific medication adherence, where predictors for adherence such as patient behavior and patient-provider interaction in TB treatment have been explored. The resulting tool will help TB medical professionals identify not only TB patients with poor adherence but also potential reasons for nonadherence and help them to design and implement targeted interventions to improve adherence [178]. …”

Nonadherence to Antituberculosis Medications: The Impact of Stigma and Depressive Symptoms

“…1 In China, more than 40% of TB patients do not comply adequately with anti-TB treatments. 2,3 This high level of nonadherence is of great concern, given the serious consequences of treatment failure and the transmissibility and drug resistance of the disease. Interventions that improve medication adherence in TB patients are, therefore, urgently needed.…”

Non-adherence to anti-tuberculosis treatment among internal migrants with pulmonary tuberculosis in Shenzhen, China: a cross-sectional study

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