Sociodemographic characteristics of respondents.

This study addresses a key challenge in HIV care the lack of a validated screening tool for psychosocial vulnerability. Although the 12-item Brief Berger HIV Stigma Scale is widely used, no clear threshold exists to identify individuals at high risk for mental health problems. Our research aimed to establish a practical, data-driven cut-off score for the scale in a Nigerian context and to explore which dimensions of stigma are most linked to psychosocial vulnerability. We conducted a cross-sectional study of 285 people living with HIV (PLHIV) at three tertiary centres (May–August 2024). Psychosocial vulnerability was defined as moderate-to-severe depression (Patient Health Questionnaire-9 ≥ 10) or anxiety (Generalised Anxiety Disorder-7 ≥ 10). The Receiver Operating Characteristic (ROC) analysis with the Youden Index identified the optimal cut-off; multivariable logistic regression examined independent associations of stigma subscales with vulnerability. Among 285 participants (mean age 47.1 ± 11.17 years, 72.6% female), 44.9% met vulnerability criteria. The Berger Scale demonstrated acceptable discrimination (AUC = 0.717, 95% CI 0.658–0.777). A cut-off of ≥30 yielded high sensitivity (87.5%) and strong negative predictive value (82.8%). Internal validation confirmed stability (cross-validated AUC 0.703, bootstrap AUC 0.701). Decision curve analysis showed positive net benefit over “screen-none” up to threshold probability 0.45, with peak benefit at 0.30. In multivariable analysis, public attitude concerns were the strongest predictor (adjusted OR 1.68, p External validation is essential before widespread adoption. Public attitude concerns outweighing internalised stigma highlights the need for culturally informed interventions addressing societal stigma alongside mental health support.