Development and Validation of the OSA-CPAP Perceived Competence Evaluation Interview.

ABSTRACT

INTRODUCTION: Continuous positive airway pressure (CPAP) is one of the most common therapies for Obstructive Sleep Apnea (OSA). We present a brief, patient-reported outcome measure used to assess patients' levels of adherence with CPAP treatment. METHODS: A questionnaire was developed based on academic literature. We qualitatively tested a pool of 18 items. It was tested in a sample of 174 patients from the Hospital La Princesa. Next, 1021 patients from Catalonia were evaluated. RESULTS: 5 items were removed. Nominal groups referred to three areas general knowledge about OSA and its risks; CPAP treatment information and expectations; CPAP use, monitoring, and confidence with its use. The 13 retained items maintained the same meaning as the original questionnaire (r=.986; p<.001) and the three proposed dimensions detected a significant increase in general knowledge of OSA (t[173]=8.097, p<.001); CPAP treatment information (t[173]=15.170, p<.001); and CPAP use (t[173]=14.642, p<.001). The final 12-item version was reliable (CRI=.793) and its internal structure was adequate (χ2[51]=72.073; p=.027, CFI=.967, RMSEA=.020 [.000, .030]). Women had a better general knowledge of OSA (t[1,018]=2.190, p=.029), CPAP treatment information (t[1,018]=2.920, p=.004), and higher overall OSA-CPAP scores (t[1,018]=3.093, p=.002). Scores were positively related to quality of life and motivation, adherence was positively related to CPAP use and monitoring, and the total score was negatively related to daytime sleepiness. CONCLUSIONS: The interview could help clinicians prevent some dropouts by targeting patients with lower adherence. It's a tool for assessing patient adherence to CPAP and to promote strategies through education and external motivational stimuli.