The Development and Psychometric Evaluation of the Survey of Obstructive Sleep Apnea Functional Health Literacy

Abstract

Background and Objective Obstructive sleep apnea (OSA) is a highly prevalent disorder that disparately affects racial/ethnic minorities. OSA functional health literacy can contribute to health disparities. Documenting poor OSA functional health literacy is needed to inform research agendas, policy, and advocacy efforts. The objective of this study is to develop a scale for measuring OSA functional health literacy among diverse audiences and a variety of reading levels and to ascertain its reliability and validity. Methods Development of the 18-item Survey of OSA Functional Health Literacy (SOFHL) was guided by literature review and input from experts. A convenience sample of persons enrolled in a clinical trial completed the survey (n = 194). Factor analysis was used to identify the number of dimensions in the SOFHL and their relationship to other domains that are relevant to OSA functional health literacy. Internal consistency reliability (alpha) was estimated for the SOFHL scales and correlations with educational attainment and income computed. Results All respondents were Black and 29% reported average household income less than $10000 USD. Confirmatory factor analysis provided support for two dimensions: OSA general knowledge (alpha = 0.81) and OSA self-management efficacy (alpha = 0.71). OSA general knowledge was significantly correlated with education (r = 0.41) and income (r = 0.21), and OSA self-management efficacy was significantly correlated with education (r = 0.19) and less depression (r = -0.18). Conclusions Higher educational attainment and socioeconomic status were associated with better OSA functional health literacy. These results provide preliminary support for the SOFHL, a measure that can be used to assess OSA functional health literacy.

Keywords

• obstructive sleep apnea
• sleep disorders
• health literacy
• surveys and questionnaires