Cross-cultural equivalence of the Kessler psychologicald distress Scale (K10) across four African countries in a multi-national study of adults

Abstract

he Kessler Psychological Distress Scale (K10) has been widely used to screen psychological distress across many countries. However, its performance has not been extensively studied in Africa. The present study sought to evaluate and compare measurement properties of the K10 across four African countries: Ethiopia, Kenya, Uganda, and South Africa. Our hypothesis is that the measure will show equivalence across all. Data are drawn from a neuropsychiatric genetic study among adult participants (N = 9179) from general medical settings in Ethiopia (n = 1928), Kenya (n = 2556), Uganda (n = 2104), and South Africa (n = 2591). A unidimensional model with correlated errors was tested for equivalence across study countries using confir- matory factor analyses and the alignment optimization method. Results displayed 30 % noninvariance (i.e., variation) for both intercepts and factor loadings across all countries. Monte Carlo simulations showed a cor- relation of 0.998, a good replication of population values, indicating minimal noninvariance, or variation. Items “so nervous,” “lack of energy/effortful tasks,” and “tired” were consistently equivalent for intercepts and factor loadings, respectively. However, items “depressed” and “so depressed” consistently differed across study coun- tries (R2 = 0) for intercepts and factor loadings for both items.