Diagnostic Yield and Clinical Impact of Trichoscopy in Alopecia: A Cross-Sectional Study From a Rural Tertiary Care Centre

Background and objective Alopecia encompasses a heterogeneous group of scarring and non-scarring disorders that often have overlapping clinical features, complicating diagnosis when scalp biopsy is unavailable. The real-world diagnostic yield of trichoscopy in rural Indian populations remains incompletely characterised. The objective of this study is to evaluate the diagnostic yield of trichoscopy, quantify its capacity to alter or refine provisional clinical diagnoses, and assess its role in reducing invasive investigations. Methods A hospital-based cross-sectional study enrolled 200 consecutive alopecia patients at a rural tertiary care centre over 18 months (April 1, 2024, to October 1, 2025). Trichoscopy was performed with a handheld dermatoscope (Illuco IDS-1100; ILLUCO Co., Ltd., Gyeonggi-do, Republic of Korea). A provisional diagnosis was recorded prior to trichoscopy; outcome was classified as confirmed, refined, or inconclusive against the final composite diagnosis. Discriminatory features were analysed by chi-square and Fisher's exact tests. Results Trichoscopy was diagnostically contributory in 195/200 (97.5%): confirming the diagnosis in 190/200 (95.0%), refining it in 5/200 (2.5%), and being inconclusive in 5/200 (2.5%). Two cases (2/200, 1.0%) of presumed alopecia areata were re-diagnosed as tinea capitis on identification of comma hairs, averting inappropriate corticosteroid therapy; three cases (3/200, 1.5%) of presumed telogen effluvium were re-diagnosed as female pattern hair loss based on hair diameter diversity >20%. Comma hairs demonstrated 78.6% sensitivity (11/14) and 100% specificity (186/186) for tinea capitis (p < 0.001), directed targeted KOH testing (12/14, 85.7% positive yield), and limited the diagnosis-deciding scalp biopsy rate to 2/200 (1.0%). Conclusions Trichoscopy shows strong potential as a first-line, non-invasive triage tool in routine dermatology practice, particularly in resource-limited settings where it may help confirm diagnoses, avert mismanagement, and reduce the need for invasive investigations; multi-centre validation against an independent reference standard is needed before this can be firmly established.