Learning Objective 1: Know a methodological approach of a questionnaire with evidences of reliability, practicability, acceptability, ceiling and floor effects; known groups and criterion validity.
Learning Objective 2: Get to know a questionnaire aimed at measuring satisfaction with drug therapy, translated into Brazilian portuguese and assessed among outpatients with coronary heart disease.
Methods: 100 outpatients with coronary heart disease in Brazil, were enrolled. Data were collected between June/2010–May/2011 at two different moments. At baseline, sociodemographic and clinical data were gathered. TSQM and the scale for measuring generic satisfaction with medication were applied by interview in order to measure Satisfaction with the drug therapy. Adherence to drug use was measured by the Morisky Self-Reported Scale and by quantifying the proportion of adherence. Seven days after baseline, the TSQM was reapplied (test-retest) in a major portion of individuals (n=73) who participated of the first application. Statistical analyses concerned: ceiling and floor effects (10% best and worst possible results of the scale), practicability (time spent during TSQM application), acceptability (percentage of unanswered items and proportion of patients who did not answer all items), reliability (regarding internal consistency and stability of the measure) and validity (Spearman correlation’s coefficient to test the relation between the scores of the Brazilian TSQM and the Morisky Scale, proportion of drug adherence and the generic measure of satisfaction with drug therapy).
Results: Regarding practicability, short time for application of the TSQM was evidenced (4.6 minutes). As for acceptability, only 7,1% of the items were not answered. Ceiling effect was verified in Side Effects domain. Floor effect was not observed. Evidences of reliability were demonstrated in all domains. Significant positive correlations of low-moderate magnitude were verified between the TSQM scores and the general measure of satisfaction.
Conclusion: The Brazilian TSQM presents evidence of practicability, acceptability, reliability and validity. Further studies with diverse populations are recommended to abroad its validity.