Affiliation:
1. Andalusian Health Service, Málaga Biomedical Research Institute (IBIMA-Plataforma BIONAND), University of Málaga, 29590 Málaga, Spain
2. Research Unit Instituto CUDECA de Estudios e Investigación en Cuidados Paliativos Fundación CUDECA, Biomedical Research Institute (IBIMA-Plataforma BIONAND), University of Málaga, 29590 Málaga, Spain
3. Multiprofessional Teaching Unit for Family and Community Care of the Málaga-Guadalhorce Primary Care District, 29009 Málaga, Spain
4. Andalusian Health Service, 29010 Malaga, Spain
Abstract
Background: To carry out a validation questionnaire that assesses beliefs about inhaled treatments in patients with chronic obstructive pulmonary disease (COPD), as knowing patients’ beliefs could help to improve medication adherence and health outcomes. Methods: We evaluated data from 260 COPD patients from electronic medical record databases from five primary healthcare centers, in a descriptive, cross-sectional study with a sample size calculated for a 10-item questionnaire, with an estimated Cronbach’s alpha of 0.70 and a 95% confidence level. Study participants were selected via systematic random sampling. Variables: Ten-item Inhaled Therapy Beliefs Questionnaire, CCTI-Questionnaire v.2.0, time for completion, age, sex, educational level, spirometry severity (GOLD criteria), exacerbations (previous year), characteristics of inhaled treatment, and smoking habit. A two-year follow-up in a subsample of 77 patients from one health center was utilized. The Morisky–Green test, pharmacy dispensing data, test–retest (kappa coefficient), and an exploratory analysis of the adherence–belief relationship (ji-squared) were measured. Results: The 10-item questionnaire showed good viability (3 min completion time) when performed face-to-face or telephonically; its psychometric properties were acceptable, with an internal consistency (Cronbach’s alpha) score of 0.613. Three factors explained 47.58% of the total variance (p < 0.0001): use (factor 1), effects (factor 2), and objectives (factor 3) of inhalers. The two-year follow-up ultimately considered 58 out of the 77 patients (10 deceased, 4 unlocated, 2 mistakes, 2 no inhaled treatment, and 1 withdrawal). Non-adherence was 48.3% in terms of the Morisky–Green test; 31% in terms of pharmacy dispensing data; and 40.4% considering both methods. There was low test–retest reliability, indicated by items 4, 8, and 9 of the CCTI-Questionnaire (Kappa = 0.4, 0.26, and 0.34; p-value < 0.0001, 0.008, and 0.001, respectively). There was mild correlation between beliefs and adherence. Conclusions: The ten-item CCTI-Questionnaire v.2.0 demonstrated acceptable psychometric properties regarding feasibility, reliability, and content validity.
Funder
Andalusian Society of Community and Family Medicine
Malaga-Valle Guadalhorce Health District of Andalusia