Geometrically Evident: Framing Studies Using the Graphic Appraisal Tool for Epidemiology (GATE)

Abstract

Educatorsinevidence-basedmedicine(EBM)havenotedthat the core set of epidemiological concepts outlined instandardsources(GuyattandRennie,2002;Strausetal.,2005) are sometimes put to use as oversimplifiedchecklists for the appraisal of research reports. This canparadoxically cloud the usefulness of tools that werespecifically designed to spur critical thinking. Extendedin-depthappraisaleffortscanalsogetlostintheminutiaeof sorting formulae and calculating numbers. Given thisstateofaffairsVonecoincidingwithmedicaleducation_songoing incorporation of EBM principlesVa team ledby New Zealand epidemiologist Rod Jackson developedthe Graphic Appraisal Tool for Epidemiology (GATE;Jackson et al., 2006). The GATE was designed as a waycombat, by visual means, a formulaic approach toappraisingthescientificliterature.TheGATEisavailableon the Journal’s website at www.jaacap.com via theArticle Plus feature.By prompting the reader to explore the structure ofclinical studies by ‘‘hanging’’ their different elements ontoits ‘‘frame,’’ GATE teaches core principles of epidemio-logical study design while also serving as a practical toolfor applying the results of stu dies to particular patients.Furthermore, the GATE is free and available online as anExcel workbook. The elegance of the tool can best beappreciatedinitsspreadshee tformat,withfeaturessuchascolor coding to identify errors in data entry, automaticcalculations of summary statistics and confidence inter-vals, and pop-up windows with hints on the EBMprocess. Quite apart from these user-friendly aspects, webelieve that the real didactic value of the GATE is inconveying core epidemiology and study design concepts.Inthiscolumn,wedefineanddeconstructtheGATEframe, exemplify its use by applying it to a widelyknown study in child and adolescent psychiatry(Treatment for Adolescents With Depression Study[TADS], 2004), note the core appraisal and epidemiol-ogy principles that are highlighted through its use, andproposeapplicationsfortheGATEinclinical,teaching,and research settings.