Abstract
BACKGROUND: China's Sexual Self-Defense Capacity (SSDC) assessment evaluates mentally disordered females' ability to protect sexual rights, critically impacting rape adjudication. Despite 3-5× higher sexual assault risk in this population, key SSDC impairment predictors-Intellectual Level (FSIQ/VIQ/PIQ) and Activities of Daily Living (ADL)-face standardization challenges due to regional variations in assessment tools/thresholds. METHODS: Retrospective analysis of 398 forensic SSDC cases (2020-2024) from five Chinese institutions, following national guidelines. Univariate, correlation, regression, ROC, and combined modeling analyses identified predictors. RESULTS: (1) ADL score exerted the strongest effect on CSSAS, followed by FSIQ. (2) Critical thresholds established: Retained SSDC (CSSAS score≥21): ADL score ≤ 22.5 or FSIQ≥66.5; Diminished SSDC score(7≤CSSAS<21): 22.531.5 or FSIQ<53.5(3) Combined model (ADL score+FSIQ) achieved higher AUC than single factors. CONCLUSION: (1) Both ADL and FSIQ are significant factors influencing SSDC. (2) ADL demonstrates superior predictive efficacy compared to FSIQ. (3) The combined predictive model (ADL + FSIQ) outperforms the use of FSIQ alone. (4) The predictive efficacy of the combined ADL-FSIQ model failed to exceed that of the ADL-only model. (5) The comprehensive use of ADL and FSIQ assessments can effectively improve the accuracy of SSDC evaluation in forensic psychiatric expertise, facilitating rape identification and sentencing. It also helps law enforcement preliminarily judge the SSDC of involved individuals, guide targeted criminal investigations, and initiate forensic procedures promptly.