Factorial structure of the perception of risk factors for type 2 diabetes scale: exploratory and confirmatory factor analyses

Rationale, aims and objectives The extent to which individuals' perceptions of risk for type 2 diabetes are related to their actual risks and health-promoting behaviours is not well known. Yet perception of risk for type 2 diabetes may influence the likelihood that individual would engage in preventive behaviours. The purpose of this study was to evaluate the psychometric properties of the perception of risk factors for type 2 diabetes (PRF-T2DM). Methods A descriptive, correlational, methodological design was used to conduct this study. The sample consisted of 629 adults from 42 states of the United States. A demographic questionnaire, the PRF-T2DM, the health-promoting lifestyle profile II and the depressive cognition scale were used to collect the data. Data analyses consisted of descriptive statistics, scale and item analyses, Pearson's correlation analysis, and exploratory and confirmatory factor analyses. Results The PRF-T2DM has a Cronbach's alpha of 0.81. Both extracted factors had Cronbach's alphas of 0.74 and 0.80, respectively. Most inter-item and item-to-total correlation coefficients for factor 1 and factor 2 met the recommended criteria of r = 0.30 to r = 0.70. The PRF-T2DM achieved all minimum recommended criteria for model fit (chi 2/d.f. = 2.33, goodness of fit index = 0.95, adjusted goodness of fit index = 0.93, comparative fit index = 0.94, root mean square error of approximation = 0.05, root mean residual = 0.05 and the P value for test of close fit = 0.33). Conclusions All statistical estimates and measures of model fit were above the standard recommended criteria. The scale has potential uses in research and clinical practice. Further development and psychometric evaluation of the PRF-T2DM is warranted.