{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T16:55:52Z","timestamp":1791305752777,"version":"4.3.1"},"reference-count":36,"publisher":"Oxford University Press (OUP)","issue":"5","license":[{"start":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T00:00:00Z","timestamp":1791244800000},"content-version":"vor","delay-in-days":49,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,8,18]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Literature around the health impact of a vegetarian diet is expanding, yet exposure measurement and its effect on the study results receive far less attention. The aim of our study was to show the effect of bias from exposure misclassification on the direction, amount, and uncertainty of study results.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We included 11\u2009180 participants from the National Health and Nutrition Examination Survey (2007\u201310). The exposure was self-reported diet type (being vegetarian). Using sensitivity, specificity, and positive and negative predictive values as bias parameters, we quantified the effect of exposure misclassification in non-differential and differential scenarios. We compared conventional analysis with bias-adjusted results.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Among self-reported vegetarians (2.2%), more than half (68%) reported consuming meat, poultry, or fish in the 24-hour dietary recalls. The sensitivity of self-reported diet type was 32% (95% CI, 0.26\u20130.38) and the specificity was 98% (95% CI, 0.98\u20130.99). The exposure misclassification was differential. The quantitative bias analysis of differential exposure misclassification was more informative. Using positive and negative predictive values as bias parameters was helpful to avoid negative bias-adjusted cell counts.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Assessing the impact of exposure misclassification in the self-reported vegetarian diet on four health outcomes, our study demonstrates that quantitative bias analysis can help to make more plausible assumptions about the possible direction, strength, and uncertainty of bias and its impact on the effect estimates of conventional analysis. However, comparing different scenarios showed that the model assumptions play a key role in the informative value of quantitative bias analysis.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/ije\/dyag168","type":"journal-article","created":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T11:51:28Z","timestamp":1790855488000},"source":"Crossref","is-referenced-by-count":0,"title":["Exposure misclassification of self-reported vegetarian diet and its impact on health outcomes"],"prefix":"10.1093","volume":"55","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4649-933X","authenticated-orcid":false,"given":"Narges","family":"Ghoreishi","sequence":"first","affiliation":[{"name":"Institute of Public Health, Charit\u00e9\u2014University Medical Center Berlin , Berlin,","place":["Germany"]},{"name":"Department of Exposure, German Federal Institute for Risk Assessment (BfR) , Berlin,","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7169-2620","authenticated-orcid":false,"given":"Tobias","family":"Kurth","sequence":"additional","affiliation":[{"name":"Institute of Public Health, Charit\u00e9\u2014University Medical Center Berlin , Berlin,","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sven","family":"Kn\u00fcppel","sequence":"additional","affiliation":[{"name":"Department of Food and Feed Safety in the Food Chain, German Federal Institute for Risk Assessment (BfR) , Berlin,","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthew P","family":"Fox","sequence":"additional","affiliation":[{"name":"Department of Epidemiology, Boston University School of Public Health , Boston, MA,","place":["United States"]},{"name":"Department of Global Health, Boston University School of Public Health , Boston, MA,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,10,6]]},"reference":[{"key":"2026100612272530300_dyag168-B1","doi-asserted-by":"publisher","first-page":"1118","DOI":"10.3390\/nu9101118","article-title":"A new approach to assess lifetime dietary patterns finds lower consumption of animal foods with aging in a longitudinal analysis of a health-oriented adventist population","volume":"9","author":"Martins","year":"2017","journal-title":"Nutrients"},{"key":"2026100612272530300_dyag168-B2","doi-asserted-by":"publisher","first-page":"1564","DOI":"10.1017\/S136898001700026X","article-title":"Diet quality on meatless days: national health and nutrition examination survey (NHANES), 2007\u20132012","volume":"20","author":"Conrad","year":"2017","journal-title":"Public Health Nutr"},{"key":"2026100612272530300_dyag168-B3","doi-asserted-by":"publisher","first-page":"3283","DOI":"10.1016\/j.clnu.2020.02.037","article-title":"Health outcomes associated with vegetarian diets: an umbrella review of systematic reviews and meta-analyses","volume":"39","author":"Oussalah","year":"2020","journal-title":"Clin Nutr"},{"key":"2026100612272530300_dyag168-B4","doi-asserted-by":"publisher","first-page":"1029","DOI":"10.1093\/ije\/dyw319","article-title":"Fruit and vegetable intake and the risk of cardiovascular disease, total cancer and all-cause mortality\u2014a systematic review and dose-response meta-analysis of prospective studies","volume":"46","author":"Aune","year":"2017","journal-title":"Int J Epidemiol"},{"key":"2026100612272530300_dyag168-B5","doi-asserted-by":"crossref","DOI":"10.1093\/oso\/9780195113242.001.0001","volume-title":"Diet, Life Expectancy, and Chronic Disease: Studies of Seventh-Day Adventists and Other Vegetarians","author":"Fraser","year":"2003"},{"key":"2026100612272530300_dyag168-B6","doi-asserted-by":"publisher","first-page":"3575","DOI":"10.1016\/j.tjnut.2024.08.004","article-title":"Trends in plant-based diets among united states adults, 1999\u2013March 2020","volume":"154","author":"Sullivan","year":"2024","journal-title":"J Nutr"},{"key":"2026100612272530300_dyag168-B7","doi-asserted-by":"publisher","first-page":"473","DOI":"10.1111\/nbu.12592","article-title":"Examining dietary behaviours, diet quality, motives and supplementation use in physically active individuals following vegetarian-based eating patterns","volume":"47","author":"Craddock","year":"2022","journal-title":"Nutr Bull"},{"key":"2026100612272530300_dyag168-B8","doi-asserted-by":"crossref","first-page":"1608","DOI":"10.1039\/D2FO03167A","article-title":"Metabolic and nutritional biomarkers in adults consuming lacto-ovo vegetarian, vegan and omnivorous diets in Spain. 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