Evidence of validity for the online version of the assessment of adherence to antiretroviral therapy questionnaire

Abstract

A Patient-Reported Outcome (PRO) measure titled Cuestionario para la Evaluación de la Adhesión al Tratamiento Antiretroviral (acronym CEAT-VIH) is currently available in paper-and-pencil and digital (online assessment) formats. Due to the advantages of online assessment, the main objective of this work was to evaluate psychometric properties of the online version, in an international sample, to accumulate evidence of its validity and provide score norms for the questionnaire. A psychometric study was performed with an international sample of 1,470 participants, from 30 countries, to accumulate evidence of CEAT-VIH validity regarding internal structure and related external criterion (e.g., viral load, number of pills, and AIDSrelated symptoms). Descriptive statistics and normative data for scores are also presented. The majority of participants were men (72.4%), aged 15 to 78 years old (M = 39.3, SD = 12.6). A unidimensional model with five facets occurred as the observed variables converged, which presented a good model fit (comparative fit index [CFI] = 1.000; Tucker–Lewis index [TLI] = 0.999; standardized root mean square residual [SRMR] = 0.027; and root mean square error of approximation [RMSEA] [90% confidence interval, CI] = 0.009 [0.000, 0.038], p = .995). There was a weak invariance for the CEAT-VIH structure for language versions and countries. Cronbach’s alpha values for the instrument (17 items) were acceptable across language versions (.88-.96). Evidence of validity related to external criteria was achieved by associations (e.g., Spearman and Mann–Whitney) between CEAT-VIH scores and relevant clinical (e.g., CD4+ cells, viral load, number of pills, and AIDSrelated symptoms) and sociodemographic (e.g., gender, age, employment status, education level, place of residence, and participation at local AIDS association) variables. In conclusion, the overall data on the evaluated psychometric properties allow recommendation of the use of this instrument in research and applied settings.