Category: Extrapolation of research findings. These pages discuss some of the issues that you should consider when evaluating whether it is appropriate to extrapolate research finding to a different group of patients or to a different practice. Articles are arranged by date with the most recent entries at the top. You can find the theme and closely related categories and other resources at the bottom of this page.

Stats: Difficulties in generalizing research (February 15, 2006). I found this information thanks to an email in the Evidence-Based Health email discussion group. Someone asked if there was any empirical evidence that the setting of a study (e.g., primary versus secondary care) could influence the results of the research. Intuitively, you would suspect that this would be the case, because the types of patients who show up at a primary care clinic are quite different than those who show up at a secondary or tertiary care center.

Theme and closely related categories:

• Theme: Evidence based medicine
• Category: Exclusions in research

Other resources:

• How much loss to follow-up is acceptable in long-term randomised trials and prospective studies?. Description: This article reviews current literature recommendations on how low a drop-out should be in order to be acceptable. The general consensus is that 5% or less is good and that 20% or higher is bad (though some authors will say that 50% or more is bad). The authors point out that the statistical consequences of drop-outs vary from study to study and that rigid adherence to any fixed cut-off is inappropriate.

[Return to full topic list] [Read current weblog entries] This webpage was written by Steve Simon on 2007-06-18, edited by Steve Simon, and was last modified on 2008-07-08. Send feedback to ssimon at cmh dot edu or click on the email link at the top of the page.