Objectives: The Clarke questionnaire, validated in Spanish language, assesses hypoglycemia awareness in patients with type 1 diabetes. This study aimed to analyze its psychometric properties in patients with type 2 diabetes (T2DM).
Methods: This was a questionnaire validation study. Patients with T2DM and treated with insulin, sulfonylureas or glinides were consecutively recruited from six endocrinology consultations and six primary care centers. The internal structure of the 8-item Clarke questionnaire was analyzed by exploratory (training sample) and confirmatory (testing sample) factor analysis; the internal consistency using Omega's McDonald coefficient; and goodness of fit with comparative fit index (CFI, cutoff >0.9), Goodness of Fit Index (GFI, cutoff >0.9), and root mean-square error of approximation (RMSEA, cutoff <0.09), as well as unidimensionality indicators.
Results: The 265 participants (56.8% men) had a mean age of 67.8 years. Confirmatory factor analysis for one dimension obtained poor indicators: fit test (p < 0.001); CFI = 0.748; RMSEA = 0.122 and SRMR = 0.134. Exploratory factor analysis showed 2 or 3 dimensions with poor adjustment indicators. Omega's McDonald was 0.739.
Conclusions: The Spanish version of the Clarke questionnaire was not valid or reliable for assessing hypoglycemia awareness in people with T2DM in Spanish population.
Keywords: Hypoglycemia; psychometrics; questionnaires; reproducibility of results; surveys; type 2 diabetes mellitus.