Developing an adherence in hypertension questionnaire short version: MUAH-16.

The Maastricht Utrecht Adherence in Hypertension (MUAH) questionnaire provides clinicians with information about the causes of a patient's poor adherence to antihypertensive drugs. In this study, the authors aimed to develop and validate a short version of the MUAH questionnaire. After an exploratory factor analysis, the number of MUAH items was reduced. The original MUAH questionnaire (model 1) was compared with the 16-item MUAH short version (model 2). Next, this short version of MUAH (MUAH-16) with all factors correlated (model 2a) was compared with the short version of MUAH with four subscales that contribute to a global factor of adherence (model 2b). Model 1 had a poor fit to the data (χ2 269 = 663.41, P < .001, comparative fit index = 0.695, root mean square error of approximation = 0.06), and model 2 had a very good fit to the data (χ2 100 = 171.07, P < .001, comparative fit index = 0.92, root mean square error of approximation = 0.04). When comparing model 2a with model 2b, the chi-square difference of the model (Δχ2 2 = 4.06; P = .067) revealed that the fits of both models were not significantly different. These findings suggest that MUAH-16 better represents a patient's adherence to antihypertensive medication than the original MUAH questionnaire. ©2017 Wiley Periodicals, Inc.