{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,5,8]],"date-time":"2025-05-08T04:10:39Z","timestamp":1746677439396,"version":"3.40.5"},"reference-count":20,"publisher":"American Society of Tropical Medicine and Hygiene","issue":"5","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,5,7]]},"abstract":"<jats:title>ABSTRACT.<\/jats:title>\n<jats:p>The WHO has a simplified grading system for assessing trachoma. However, even for experts, it can be difficult to classify certain cases as strictly positive or negative for a given grade. Given the absence of a true gold standard, we performed a Latent Class Analysis (LCA) on a set of 200 graded photos of the superior tarsal conjunctiva. Ten trained graders assessed the presence of two trachoma grades: trachomatous inflammation\u2013follicular (TF) and trachomatous inflammation\u2013intense (TI). The LCA was modeled in two different ways: first with two classes (presence\/absence), and then with three classes, with the extra class presumed to represent a more discrepant \u201cborderline\u201d case. Cohen\u2019s \u03ba-statistics measuring agreement between graders were calculated for TF and TI grades (separately) before and after removing the third latent class. The \u03ba-statistic increased by 0.10 (95% CI = 0.72\u20130.85; <jats:italic>P<\/jats:italic> &lt;0.001) for TF and 0.13 (95% CI = 0.81\u20130.90; <jats:italic>P<\/jats:italic> &lt;0.001) for TI, indicating that the third latent class represented a discrepant-case borderline class. The identification of borderline grading cases using a three-class LCA may be useful in creating balanced grader certification examinations that represent the full spectrum of disease. Additionally, a multiclass LCA could act as a probabilistic gold standard used to train and analyze future convolutional neural network models.<\/jats:p>","DOI":"10.4269\/ajtmh.24-0321","type":"journal-article","created":{"date-parts":[[2025,2,25]],"date-time":"2025-02-25T21:42:05Z","timestamp":1740519725000},"page":"1087-1090","source":"Crossref","is-referenced-by-count":0,"title":["Identifying Borderline Trachoma Grades Using a Three-Latent Class Model"],"prefix":"10.4269","volume":"112","author":[{"given":"Vinayak","family":"Prathikanti","sequence":"first","affiliation":[{"name":"F. I. Proctor Foundation, Department of Ophthalmology, University of California, San Francisco, California;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Renee","family":"Casentini","sequence":"additional","affiliation":[{"name":"F. I. Proctor Foundation, Department of Ophthalmology, University of California, San Francisco, California;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jonathan","family":"Hwang","sequence":"additional","affiliation":[{"name":"F. I. Proctor Foundation, Department of Ophthalmology, University of California, San Francisco, California;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Amza","family":"Abdou","sequence":"additional","affiliation":[{"name":"Programme National de Lutte Contre la Cecit\u00e9, Niamey, Niger;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nassirou","family":"Beidou","sequence":"additional","affiliation":[{"name":"Programme National de Lutte Contre la Cecit\u00e9, Niamey, Niger;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Boubacar","family":"Kadri","sequence":"additional","affiliation":[{"name":"Programme National de Sante Oculaire, Niamey, Niger"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ariktha","family":"Srivathsan","sequence":"additional","affiliation":[{"name":"F. I. Proctor Foundation, Department of Ophthalmology, University of California, San Francisco, California;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Isabelle","family":"Prieto","sequence":"additional","affiliation":[{"name":"F. I. Proctor Foundation, Department of Ophthalmology, University of California, San Francisco, California;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Winnie","family":"Huang","sequence":"additional","affiliation":[{"name":"F. I. Proctor Foundation, Department of Ophthalmology, University of California, San Francisco, California;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daniel G.","family":"Eyassu","sequence":"additional","affiliation":[{"name":"F. I. Proctor Foundation, Department of Ophthalmology, University of California, San Francisco, California;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elisabeth","family":"Gebreegziabher","sequence":"additional","affiliation":[{"name":"F. I. Proctor Foundation, Department of Ophthalmology, University of California, San Francisco, California;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Corinne","family":"Pierce","sequence":"additional","affiliation":[{"name":"F. I. Proctor Foundation, Department of Ophthalmology, University of California, San Francisco, California;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hadley","family":"Burroughs","sequence":"additional","affiliation":[{"name":"F. I. Proctor Foundation, Department of Ophthalmology, University of California, San Francisco, California;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jeremy D.","family":"Keenan","sequence":"additional","affiliation":[{"name":"F. I. Proctor Foundation, Department of Ophthalmology, University of California, San Francisco, California;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Thomas M.","family":"Lietman","sequence":"additional","affiliation":[{"name":"F. I. Proctor Foundation, Department of Ophthalmology, University of California, San Francisco, California;"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"2795","reference":[{"key":"b1","series-title":"Bull World Health Organ","first-page":"477","article-title":"A simple system for the assessment of trachoma and its complications","volume":"65","author":"Thylefors","year":"1987"},{"key":"b2","series-title":"Ophthalmic Epidemiol","first-page":"162","article-title":"Inter-rater agreement between trachoma graders: Comparison of grades given in field conditions versus grades from photographic review","volume":"22","author":"Gebresillasie","year":"2015"},{"key":"b3","series-title":"Trans R Soc Trop Med Hyg","first-page":"111","article-title":"Photographic grading for trachoma diagnosis within trachoma impact surveys in Amhara region, Ethiopia","volume":"117","author":"Whitson","year":"2023"},{"year":"1981","series-title":"Guide to Trachoma Control in Programmes for the Prevention of Blindness","author":"Dawson","key":"b4"},{"key":"b5","series-title":"Invest Ophthalmol Vis Sci","first-page":"6133","article-title":"How reliable are tests for trachoma?\u2014A latent class approach","volume":"52","author":"See","year":"2011"},{"key":"b6","series-title":"Clin Infect Dis Off Dis","first-page":"743","article-title":"A cluster-randomized trial to assess the efficacy of targeting trachoma treatment to children","volume":"64","author":"Amza","year":"2017"},{"key":"b7","series-title":"PLoS Negl Trop Dis","first-page":"e1586","article-title":"Community risk factors for ocular Chlamydia infection in Niger: Pre-treatment results from a cluster-randomized trachoma trial","volume":"6","author":"Amza","year":"2012"},{"key":"b8","series-title":"PLoS Negl Trop Dis","first-page":"e1983","article-title":"The easiest children to reach are most likely to be infected with ocular Chlamydia trachomatis in trachoma endemic areas of Niger","volume":"7","author":"Amza","year":"2013"},{"key":"b9","series-title":"PLoS Negl Trop Dis","first-page":"e2115","article-title":"Mass treatment with azithromycin for trachoma: When is one round enough? Results from the PRET trial in the Gambia","volume":"7","author":"Harding-Esch","year":"2013"},{"key":"b10","series-title":"JAMA","first-page":"778","article-title":"Comparison of annual and biannual mass antibiotic administration for elimination of infectious trachoma","volume":"299","author":"Melese","year":"2008"},{"key":"b11","series-title":"JAMA","first-page":"1142","article-title":"Effect of a single mass antibiotic distribution on the prevalence of infectious trachoma","volume":"295","author":"Chidambaram","year":"2006"},{"key":"b12","series-title":"J Black Psychol","first-page":"287","article-title":"Latent class analysis: A guide to best practice","volume":"46","author":"Weller","year":"2020"},{"year":"2019","series-title":"irr: Various Coefficients of Interrater Reliability and Agreement","author":"Gamer","key":"b13"},{"year":"2023","series-title":"R: A Language and Environment for Statistical Computing","key":"b14"},{"key":"b15","series-title":"Am J Trop Med Hyg","first-page":"577","article-title":"Importance of including borderline cases in trachoma grader certification","volume":"91","author":"Gaynor","year":"2014"},{"key":"b16","series-title":"Lancet Glob Health","first-page":"e491","article-title":"Global progress toward the elimination of active trachoma: An analysis of 38 countries","volume":"10","author":"Renneker","year":"2022"},{"key":"b17","series-title":"PLoS Negl Trop Dis","first-page":"e0009928","article-title":"Evaluation of photography using head-mounted display technology (ICAPS) for district trachoma surveys","volume":"15","author":"Naufal","year":"2021"},{"key":"b18","series-title":"PLoS Negl Trop Dis","first-page":"e0010943","article-title":"Detection of trachoma using machine learning approaches","volume":"16","author":"Socia","year":"2022"},{"key":"b19","series-title":"PLoS One","first-page":"e0210463","article-title":"Sensitivity and specificity of computer vision classification of eyelid photographs for programmatic trachoma assessment","volume":"14","author":"Kim","year":"2019"},{"key":"b20","series-title":"Br J Ophthalmol","first-page":"371","article-title":"Trachoma grading: Observer trials conducted in southern Malawi","volume":"71","author":"Tielsch","year":"1987"}],"container-title":["The American Journal of Tropical Medicine and Hygiene"],"original-title":[],"link":[{"URL":"https:\/\/www.ajtmh.org\/view\/journals\/tpmd\/112\/5\/article-p1087.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.ajtmh.org\/downloadpdf\/journals\/tpmd\/112\/5\/article-p1087.xml","content-type":"text\/html","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/www.ajtmh.org\/downloadpdf\/journals\/tpmd\/112\/5\/article-p1087.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,5,7]],"date-time":"2025-05-07T14:24:29Z","timestamp":1746627869000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.ajtmh.org\/view\/journals\/tpmd\/112\/5\/article-p1087.xml"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,5,7]]},"references-count":20,"journal-issue":{"issue":"5"},"URL":"https:\/\/doi.org\/10.4269\/ajtmh.24-0321","relation":{},"ISSN":["0002-9637","1476-1645"],"issn-type":[{"type":"print","value":"0002-9637"},{"type":"electronic","value":"1476-1645"}],"subject":[],"published":{"date-parts":[[2025,5,7]]}}}