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

Abstract

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.