Validating measures of posttraumatic stress, depression, and anxiety screening among conflict‐affected internally displaced persons in Nigeria

Nigeria faces multiple overlapping violent conflicts; however, there are few validated mental health screening instruments for these conflict-affected populations. This study validated the PTSD Checklist for DSM-5 (PCL-5), Patient Health Questionnaire-9 (PHQ-9), and Generalized Anxiety Disorder-7 (GAD-7) among 205 conflict-affected people in two internally displaced persons camps in Abuja, Nigeria. Measures were translated into Hausa and Pidgin English and culturally adapted; psychiatrists also administered structured clinical diagnostic interviews. All instruments showed excellent reliability, McDonald's ωs = .866-. 915, Cronbach's αs = .864-.915. Confirmatory factor analysis favored a six-factor anhedonia model for the PCL-5 per incremental fit indices, whereas the Bayesian information criterion favored more parsimonious four-factor models. Neither the single-factor nor two-factor PHQ-9 models provided adequate fit, and the GAD-7 fit a unidimensional structure poorly. The PCL-5 showed fair criterion validity, AUC = .706, and performed best at a threshold of 38 points or higher (sensitivity: 56.3%, specificity: 76.5%), outperforming the international standard of 33. The PHQ-9 demonstrated poor criterion validity, AUC = .697. At a 10-point score threshold, sensitivity (69.7%), specificity (68.8%), and negative predictive value (82.6%) supported limited use as a first-stage screener with clinical case confirmation. The GAD-7 demonstrated even lower criterion validity, AUC = .576. Within this population, estimated PTSD (50.2%), depression (32.4%), and anxiety (44.9%) prevalences were high, with comorbid presentations in 40.5% of participants. Population-specific score thresholds improved PCL-5 diagnostic accuracy, and the PCL-5 and PHQ-9 can support screening in this population; the GAD-7 requires further evaluation or supplementation.