Diagnostic Contribution of Histopathology in Medicolegal Autopsy: A Denominator-Specific Systematic Review

Background/Objectives: Published estimates of histopathological examination (HPE) contribution in medicolegal autopsy use different denominators and outcome definitions. We examined what these estimates measure and their implications for practice. Methods: PubMed, Embase, Web of Science, and Scopus were searched from inception to 31 May 2026 (PROSPERO CRD420261401909). Eligible studies reported denominator-specific HPE contribution. Cause of death (COD) provision and change were distinguished from manner change, confirmation, refinement, and targeted forensic interpretation. JBI checklists supported item-level appraisal. Findings were synthesized narratively without pooling. Results: Twenty-one studies were included from 2287 identified records. Strict COD change was reported in 0/100 uncomplicated hanging suicides and 1/189 gross-clear medicolegal autopsies. A broad systematic-histology cohort reported histology-only COD provision in 36/428 cases. In separate unresolved-COD populations, studies reported COD provision in 49/203 and 40/71 cases. These results address different diagnostic questions and do not establish a relationship between uncertainty and yield. Selected denominators, composite outcomes, and incomplete separation from other investigations limited interpretation. Confirmation, injury assessment, and organ-specific findings represented additional functions. Conclusions: There is no single transferable HPE yield: the pre-HPE diagnosis, denominator, outcome definition, and contribution of other investigations must accompany each estimate. The review supports clearer reporting and interpretation of HPE contribution; low rates of COD change do not establish when histology can safely be omitted.