{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T09:54:12Z","timestamp":1775728452826,"version":"3.50.1"},"reference-count":35,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T00:00:00Z","timestamp":1775692800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vision"],"abstract":"<jats:p>(1) Background: To synthesize available evidence on the prevalence of keratoconus (KC) reported in Indian study populations and describe its demographic distribution. (2) Methods: PubMed, Embase, and Scopus were checked using free text and controlled vocabulary. A random-effect meta-analysis of pooled prevalence and its 95% confidence intervals (CIs) for KC among study participants recruited in India was conducted using exact binomial distributions and the Freeman\u2013Tukey double-arcsine transformation. To identify potential sources of variability, we conducted subgroup analyses by dividing the data by geographic region, KC assessment, and study population. The methodological quality of each study was assessed using the Newcastle\u2013Ottawa scale (NOS). Evidence quality was evaluated using the GRADE system. (3) Results: Across included studies, the total number of KC cases was 16,164, and sample sizes ranged from 152 to 2,384,523 participants. Prevalence estimates varied markedly across studies, reflecting substantial heterogeneity in study design, diagnostic criteria, and population characteristics. Most studies were conducted in high-risk clinical settings, limiting generalizability to the general population. Subgroup analyses showed no significant differences by geographic region or diagnostic modality (p = 0.79 and 0.07, respectively). There was a statistically significant subgroup effect (p &lt; 0.001) in the study population. The reported prevalence among females ranged from 0.00 to 0.04, while the pooled prevalence estimate was 0.02 (95% CI: 0.00\u20130.04). Four cross-sectional studies scored 8\u201310 on the NOS. (4) Conclusions: Our meta-analysis synthesized the currently available evidence on keratoconus prevalence across Indian study populations, highlighting substantial variability across studies and emphasizing that estimates should be interpreted within their specific study contexts rather than as representative of the national population.<\/jats:p>","DOI":"10.3390\/vision10020020","type":"journal-article","created":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T07:48:07Z","timestamp":1775720887000},"page":"20","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Epidemiology of Keratoconus in India: A Systematic Review and Meta-Analysis of Indian Study Populations"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7968-1336","authenticated-orcid":false,"given":"Matteo","family":"Ripa","sequence":"first","affiliation":[{"name":"Department of Ophthalmology, Sankara Eye Hospital, Jaipur 302039, Rajasthan, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chiara","family":"Schipa","sequence":"additional","affiliation":[{"name":"Catholic University \u201cSacro Cuore\u201d, 00168 Rome, Italy"},{"name":"Department of Emergency, Anesthesiological and Reanimation Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0228-0603","authenticated-orcid":false,"given":"Paola","family":"Aceto","sequence":"additional","affiliation":[{"name":"Catholic University \u201cSacro Cuore\u201d, 00168 Rome, Italy"},{"name":"Department of Emergency, Anesthesiological and Reanimation Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sushad","family":"Prasad","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Sankara Eye Hospital, Krishnankoil 626190, Tamil Nadu, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Neeraj Apoorva","family":"Shah","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Sankara Eye Hospital, Jaipur 302039, Rajasthan, India"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1619","DOI":"10.1007\/s10792-020-01455-9","article-title":"New Treatments for Keratoconus","volume":"40","author":"Pedrotti","year":"2020","journal-title":"Int. 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