Effect of Existential Counselling on Depressive and Generalized Anxiety Symptoms among Inmates in Maiduguri, Northeastern Nigeria: A Randomized Controlled Study

Background: Incarcerated populations experience a high burden of psychological distress, yet evidence-based, culturally adapted psychotherapeutic interventions remain scarce in low- and middle-income countries (LMICs). Aim: To evaluate the effect of Maiduguri Monotheist Existential Counselling (MMEC) on depressive and generalized anxiety symptoms among inmates in Maiduguri, Northeastern Nigeria. Methods: A parallel, two-arm randomized controlled trial was conducted at the Maiduguri Medium Security Custodial Centre. Out of 144 inmates initially screened, 96 participants with mild-to-moderate symptoms confirmed via the Mini-International Neuropsychiatric Interview (M.I.N.I. 7.0) were randomized into either the MMEC intervention arm (n = 48) or a waiting-list control arm (n = 48). The intervention was delivered sequentially across six distinct cohorts over a total span of nine weeks (1.5 weeks per cohort). Primary outcomes were evaluated using the GAD-7 and PHQ-9 scales at baseline and 4 weeks post-intervention. Analysis was conducted on a per-protocol basis (n = 47 intervention, n = 48 control). Results: The MMEC intervention group demonstrated a statistically significant reduction in anxiety symptoms, with median GAD-7 scores falling from 12.5 to 9.0 (Z = -4.341, p < 0.001), yielding a large effect size (r = 0.633). Depressive symptoms also decreased significantly, with median PHQ-9 scores shifting from 17.5 to 12.0 (Z = -5.532, p < 0.001), demonstrating a robust effect size (r = 0.760). In contrast, the control group showed no statistically significant alterations in anxiety (p = 0.628) or depression (p = 0.588) over the identical temporal window. Post-intervention between-group analysis confirmed that both anxiety and depression scores were significantly lower in the intervention group compared to the control group (p < 0.001). Conclusion: Culturally and structurally adapted existential counselling is highly effective at reducing symptoms of anxiety and depression within resource-constrained correctional environments.