Uso del índice de cambio fiable en la evaluación de la efectividad de intervenciones clínicas: aplicación en un programa formativo en asma

OBJECTIVE: To compare two methods for the evaluation of outcomes to assess effectiveness of a therapeutic intervention of a professional education program on asthma control. DESIGN: A naturalistic, intervention study in which asthmatic patients were attended by clinicians (IG group) who Had taken part in a special education program and a control group (CG) that received medical assistance from clinicians still waiting to be trained. LOCATION: Five urban Primary Care Health Centres of the same region. PARTICIPANTS: From an initial sample of 100 patients, 76 formed the final sample for analysis. The study included 37 males and 39 females, aged between 18 and 65 years (M=41.2 years). The two study groups were found to be homogeneous except for the sex variable. INTERVENTION: Training program for clinical treatment adherence. MAIN MEASUREMENTS: Peak flow as spirometric index, and structured interview. STATISTICAL ANALYSIS: The results were initially analysed using classical techniques based on robust ANOVA models, and then by calculating the Reliable Change Index (RCI). RESULTS: ANOVA models, conducted separately for each sex, showed no significant differences, due to sample size. RCI methodology showed significant differences in the percentage of patients improved in both groups, as well as clinically relevant changes being observed individually. CONCLUSIONS: The RCI method is presented as an attractive alternative as regards the classical methods of analysis that can help in the clinical decision.