{"id":1139,"date":"2015-07-31T20:25:08","date_gmt":"2015-07-31T19:25:08","guid":{"rendered":"http:\/\/stg-blogs.bmj.com\/adc\/?p=1139"},"modified":"2015-07-26T18:36:04","modified_gmt":"2015-07-26T17:36:04","slug":"predictive-factors","status":"publish","type":"post","link":"https:\/\/stg-blogs.bmj.com\/adc\/2015\/07\/31\/predictive-factors\/","title":{"rendered":"Predictive Factors"},"content":{"rendered":"<p><img loading=\"lazy\" decoding=\"async\" class=\"alignleft\" src=\"http:\/\/mynameisgigi.com\/blog\/images\/Oliver.jpg\" alt=\"\" width=\"246\" height=\"164\" \/>Sometimes, we spot stuff that predicts how things will happen. Well, usually happen. These may be described as <a href=\"https:\/\/stg-blogs.bmj.com\/adc\/2009\/03\/09\/risk-vs-prognostic-factors\/\">\u2018risk\u2019 factors &#8211; that is, factors which predict something will happen &#8211; or \u2018prognostic\u2019 factors <\/a>&#8211; thinks that predict the outcome of a condition. There are a range of generalisations that are sometimes made from \u2018predictive\u2019 studies, and if you take an extremely non-medical example you may spot some of their weaknesses.<\/p>\n<p>Say someone reports a study that shows a barking dog predicts a herd of small children in the kitchen. The study was done during daytime hours, in a family home on a suburban street. While the barking was a good predictor (85% of the time), it wasn\u2019t perfect, sometimes there was a delivery driver at the door; though preceded by hearing the van drawing up. The authors conclude that those wishing to protect the biscuits in their kitchen should use barking dogs to warn them.<!--more--><br \/>\nClearly, this only works in a home that owns a dog, and is unlikely to be applicable if you live in an apartment block, or the barking is well after bedtime. Even if you own a dog, barking while out trekking across fields won\u2019t predict kids in the kitchen (but might well signal another walker). Predictive factors are context specific.<\/p>\n<p>Now if the authors of the dog-child-kitchen study were daft enough to suggest that muzzling the dog would stop little visitors, we\u2019d be laughing at them. Predictive factors are not always causative.<\/p>\n<p>When you\u2019re reading, it\u2019s worth keeping these elements in mind. If you find a predictive factor in one study, be aware that the context may make it unhelpful &#8211; or at least, differently indicative &#8211; in another. And be very wary of anyone taking a predictive association and using this to makes claims for a treatment.<\/p>\n<p>&#8211; Archi<!--TrendMD v2.4.8--><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Sometimes, we spot stuff that predicts how things will happen. Well, usually happen. These may be described as \u2018risk\u2019 factors &#8211; that is, factors which predict something will happen &#8211; or \u2018prognostic\u2019 factors &#8211; thinks that predict the outcome of a condition. There are a range of generalisations that are sometimes made from \u2018predictive\u2019 studies, [&#8230;]<\/p>\n<p><a class=\"btn btn-secondary understrap-read-more-link\" href=\"https:\/\/stg-blogs.bmj.com\/adc\/2015\/07\/31\/predictive-factors\/\">Read More&#8230;<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[79],"tags":[],"class_list":["post-1139","post","type-post","status-publish","format-standard","hentry","category-archimedes"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/stg-blogs.bmj.com\/adc\/wp-json\/wp\/v2\/posts\/1139","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/stg-blogs.bmj.com\/adc\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/stg-blogs.bmj.com\/adc\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/stg-blogs.bmj.com\/adc\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/stg-blogs.bmj.com\/adc\/wp-json\/wp\/v2\/comments?post=1139"}],"version-history":[{"count":0,"href":"https:\/\/stg-blogs.bmj.com\/adc\/wp-json\/wp\/v2\/posts\/1139\/revisions"}],"wp:attachment":[{"href":"https:\/\/stg-blogs.bmj.com\/adc\/wp-json\/wp\/v2\/media?parent=1139"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/stg-blogs.bmj.com\/adc\/wp-json\/wp\/v2\/categories?post=1139"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/stg-blogs.bmj.com\/adc\/wp-json\/wp\/v2\/tags?post=1139"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}