{"id":333,"date":"2015-07-12T08:31:30","date_gmt":"2015-07-12T07:31:30","guid":{"rendered":"http:\/\/pcool.dyndns.org:8080\/statsbook\/?page_id=333"},"modified":"2025-06-27T20:38:03","modified_gmt":"2025-06-27T19:38:03","slug":"prevalence-incidence","status":"publish","type":"page","link":"https:\/\/pcool.dyndns.org\/index.php\/prevalence-incidence\/","title":{"rendered":"Prevalence &amp; Incidence"},"content":{"rendered":"<p><strong>Prevalence<\/strong><\/p>\n<p>Epidemiologist use prevalence and incidence as measures of how common a disease is.<\/p>\n<p><strong>Prevalence is the total number of individuals with the disease at a particular point in time divided by the population at risk. <\/strong>In other words, it is the proportion of the population that suffers from the disease.<\/p>\n<p><strong>Incidence<\/strong><\/p>\n<p><strong>Incidence is the number of NEW cases of the disease per year divided by the population at risk.<\/strong> For example there are approximately 200 new cases of osteosarcoma per year in Britain. The population of Britain is approximately 68,000,000. Therefore the Incidence of osteosarcoma is<\/p>\n<p>200 \/ 68,000,000 ~ 2.94 per million ~ 3 per million<\/p>\n<p>So, when the population and the disease are stable:<\/p>\n<p><strong>Prevalence ~ <\/strong><strong>Incidence x Mean disease duration<\/strong><\/p>\n<p>In trying to compare the influence of an exposure on a disease, it is obviously more useful to compare incidences rather than prevalences.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Prevalence Epidemiologist use prevalence and incidence as measures of how common a disease is. Prevalence is the total number of individuals with the disease at a particular point in time divided by the population at risk. In other words, it is the proportion of the population that suffers from the disease. Incidence Incidence is the [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"inline_featured_image":false,"footnotes":""},"class_list":["post-333","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/pcool.dyndns.org\/index.php\/wp-json\/wp\/v2\/pages\/333","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pcool.dyndns.org\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/pcool.dyndns.org\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/pcool.dyndns.org\/index.php\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/pcool.dyndns.org\/index.php\/wp-json\/wp\/v2\/comments?post=333"}],"version-history":[{"count":1,"href":"https:\/\/pcool.dyndns.org\/index.php\/wp-json\/wp\/v2\/pages\/333\/revisions"}],"predecessor-version":[{"id":4199,"href":"https:\/\/pcool.dyndns.org\/index.php\/wp-json\/wp\/v2\/pages\/333\/revisions\/4199"}],"wp:attachment":[{"href":"https:\/\/pcool.dyndns.org\/index.php\/wp-json\/wp\/v2\/media?parent=333"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}