Prevalence of anxiety symptoms in a Ugandan population sample and psychometric properties of the Generalized Anxiety Disorder-7 scale (GAD-7) in Luganda and Runyoro

Abstract

Background

Locally validated measures are required for robust clinical and epidemiological assessments of anxiety symptoms and disorders. Few studies on the African continent have examined the psychometric properties of the Generalized Anxiety Disorder-7 scale (GAD-7). We aimed to investigate certain psychometric properties of GAD-7 translated into Runyoro and Luganda, two Ugandan languages, and to measure the prevalence of anxiety symptoms in a Ugandan population sample.

Methods

Data were collected in 2021–22 through the African Medical and Behavioural Sciences Organization (AMBSO) Population Health Surveillance (APHS), a population cohort study in Uganda. GAD-7, Patient Health Questionnaire-9 (PHQ-9), and questions on socio-demographic factors were administered during individual face-to-face interviews. Construct validity, internal consistency, and concurrent validity of the Runyoro- and Luganda-translated GAD-7 were examined using confirmatory factor analysis (CFA), two internal consistency coefficients (Revelle’s omega total and Cronbach’s alpha), and Pearson’s correlation coefficient, respectively. The prevalence of anxiety symptoms and likely anxiety disorders was also estimated.

Results

A total of 4107 individuals aged 13–80 participated, with 2206 and 1901 speaking Runyoro and Luganda, respectively. The Runyoro-translated GAD-7 retained its one-factor structure (RMSEA = 0.097, CFI = 0.977, TLI = 0.966), had good internal consistency (omega total = 0.85), and correlated moderately with the PHQ-9 (r = 0.67, p < 0.01). The Luganda-translated GAD-7 also fit a one-factor structure (RMSEA = 0.097, CFI = 0.989, TLI = 0.983), exhibited excellent internal consistency (omega total = 0.90), and strong concurrent validity with PHQ-9 (r = 0.71, p < 0.01). Overall, participants reported low levels of anxiety symptoms. Using GAD-7 ≥ 10 binary cut-offs, the total prevalence of likely anxiety disorders was 1.5% (0.5% among males, 2.2% among females).

Conclusions

GAD-7 was translated into Runyoro and Luganda, two Ugandan languages, and both translations showed good psychometric properties. The prevalence of likely anxiety disorders was low in this diverse large Ugandan population sample, the largest population study on anxiety in Uganda to date. The low prevalence could partly be due to individuals with more severe anxiety symptoms not participating or GAD-7 not including local idioms of anxiety. Further clinical validation is required.