Determination of hand of origin from fingerprint patterns: a systematic review

Abstract Background Correct attribution of the hand of origin from isolated fingerprints is crucial in forensic identification, as it can support scene reconstruction and narrow comparison efforts. However, evidence on directional and morphometric features relevant to hand determination remains scattered across small, methodologically heterogeneous studies. Main text Following the PRISMA guidelines, Scopus, PubMed, Web of Science, and Google Scholar were searched for observational studies in adults that reported at least one ridge detail or geometric feature separately for left and right hands. Of the 191 records screened, 9 studies met the inclusion criteria and were synthesised qualitatively. Most studies focused on whorl patterns, in Indian, Spanish, Caucasian, and Egyptian populations, using rolled inked fingerprints from all ten digits. Across studies, the slope of the apex ridges consistently showed a leftward trend in the left hand and a rightward trend in the right hand, while axis slant and rotation of the central ridges also demonstrated strong lateral preferences in whorl patterns. Ridge count, ridge tracing, delta-core distances, and angular measures around the core and deltas contributed additional discriminatory value, particularly when considered in combination rather than in isolation. Conclusions This systematic review indicates that several fingerprint features, particularly the slope of the apex ridges, the axis slant, and the rotation of the central ridges, can aid in distinguishing left- and right-hand impressions, mainly in whorl patterns. However, small sample sizes, methodological heterogeneity, uneven sex distributions, and a predominant focus on specific populations and pattern types limit the generalizability of the findings and prevent conclusions about diagnostic accuracy. Standardised measurement protocols and inclusion of all fingerprint patterns are needed to validate these parameters and to support evidence-based use of hand-origin inferences in forensic casework.