{"id":367,"date":"2020-11-16T11:00:49","date_gmt":"2020-11-16T17:00:49","guid":{"rendered":"https:\/\/blogs.extension.msstate.edu\/theriskproject\/?p=367"},"modified":"2021-03-12T09:17:17","modified_gmt":"2021-03-12T15:17:17","slug":"principles-of-diagnostic-testing-series-part-3","status":"publish","type":"post","link":"https:\/\/blogs.extension.msstate.edu\/theriskproject\/principles-of-diagnostic-testing-series-part-3\/","title":{"rendered":"Principles of Diagnostic Testing Series | Part 3"},"content":{"rendered":"<h2><em><strong>Population characteristics: Prevalence<\/strong><\/em><\/h2>\n<hr \/>\n<p><strong>Prevalence<\/strong> is an estimation of an individual\u2019s risk of having a disease at a specific point in time. <strong>Apparent prevalence<\/strong>, or the proportion of test-positive individuals at a specific point in time, is found after performing a diagnostic test. Apparent prevalence may be misleading because it does not account for potential misclassification of disease due to testing errors.<a href=\"https:\/\/blogs.extension.msstate.edu\/theriskproject\/files\/2020\/10\/Diagnostic-Testing-Part-2-Prevalence-form.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-375 aligncenter\" src=\"https:\/\/blogs.extension.msstate.edu\/theriskproject\/files\/2020\/10\/Diagnostic-Testing-Part-2-Prevalence-form.jpg\" alt=\"\" width=\"381\" height=\"69\" \/><\/a> To determine the <strong>true prevalence<\/strong>\u00a0or the proportion of diseased individuals in a population, the sensitivity and specificity of the diagnostic test must be considered. Diagnostic sensitivity is the proportion of individuals with the disease that test positive. Diagnostic specificity is the proportion of individuals without the disease that test negative.<a href=\"https:\/\/blogs.extension.msstate.edu\/theriskproject\/files\/2020\/10\/Diagnostic-Testing-Part-2-true-prevalence-formula.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-376 aligncenter\" src=\"https:\/\/blogs.extension.msstate.edu\/theriskproject\/files\/2020\/10\/Diagnostic-Testing-Part-2-true-prevalence-formula.jpg\" alt=\"\" width=\"434\" height=\"61\" \/><\/a><\/p>\n<p>The true prevalence accounts for errors from the diagnostic test and better estimates the actual prevalence of the disease in a population.<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Population characteristics: Prevalence Prevalence is an estimation of an individual\u2019s risk of having a disease at a specific point in time. Apparent prevalence, or the proportion of test-positive individuals at a specific point in time, is found after performing a &hellip; <a href=\"https:\/\/blogs.extension.msstate.edu\/theriskproject\/principles-of-diagnostic-testing-series-part-3\/\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":79,"featured_media":247,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[2,6],"tags":[],"coauthors":[31],"class_list":["post-367","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-animal-health","category-epi-methods"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/blogs.extension.msstate.edu\/theriskproject\/files\/2020\/06\/Cattle-96.jpg","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p7pWHv-5V","_links":{"self":[{"href":"https:\/\/blogs.extension.msstate.edu\/theriskproject\/wp-json\/wp\/v2\/posts\/367","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.extension.msstate.edu\/theriskproject\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.extension.msstate.edu\/theriskproject\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.extension.msstate.edu\/theriskproject\/wp-json\/wp\/v2\/users\/79"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.extension.msstate.edu\/theriskproject\/wp-json\/wp\/v2\/comments?post=367"}],"version-history":[{"count":4,"href":"https:\/\/blogs.extension.msstate.edu\/theriskproject\/wp-json\/wp\/v2\/posts\/367\/revisions"}],"predecessor-version":[{"id":562,"href":"https:\/\/blogs.extension.msstate.edu\/theriskproject\/wp-json\/wp\/v2\/posts\/367\/revisions\/562"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.extension.msstate.edu\/theriskproject\/wp-json\/wp\/v2\/media\/247"}],"wp:attachment":[{"href":"https:\/\/blogs.extension.msstate.edu\/theriskproject\/wp-json\/wp\/v2\/media?parent=367"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.extension.msstate.edu\/theriskproject\/wp-json\/wp\/v2\/categories?post=367"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.extension.msstate.edu\/theriskproject\/wp-json\/wp\/v2\/tags?post=367"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/blogs.extension.msstate.edu\/theriskproject\/wp-json\/wp\/v2\/coauthors?post=367"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}