Günther Eysenbach|John Powell|Oliver Kuß|EunRyoung Sa
Toronto General Hospital|London School of Hygiene & Tropical Medicine|Toronto General Hospital|Martin Luther University Halle-Wittenberg|Health Net|Network Group (Czechia)|University of Pittsburgh|London School of Hygiene & Tropical Medicine|Toronto General Hospital|Martin Luther University Halle-Wittenberg|Health Net|Network Group (Czechia)|University of Pittsburgh|London School of Hygiene & Tropical Medicine|Toronto General Hospital|Martin Luther University Halle-Wittenberg|Health Net|Network Group (Czechia)|University of Pittsburgh
quality consumer health information world wide web important issue medicine date systematic comprehensive synthesis methods evidence performedto establish methodological framework quality web evaluated practice determine heterogeneity results conclusions compare methodological rigor studies determine extent conclusions depend methodology used suggest future directions researchwe searched medline premedline 1966 september 2001 science citation index 1997 september 2001 social sciences citation index 1997 september 2001 arts humanities citation index 1997 september 2001 lisa 1969 july 2001 cinahl 1982 july 2001 psychinfo 1988 september 2001 embase 1988 june 2001 sigle 1980 june 2001 also conducted hand searches general internet searches personal bibliographic database searchwe included published unpublished empirical studies language investigators searched web systematically specific health information evaluated quality web sites pages reported quantitative results screened 7830 citations retrieved 170 potentially eligible full articles total 79 distinct studies met inclusion criteria evaluating 5941 health web sites 1329 web pages reporting 408 evaluation results 86 different quality criteriatwo reviewers independently extracted study characteristics medical domains search strategies used methods criteria quality assessment results percentage sites pages rated inadequate pertaining quality criterion quality rigor study methods reportingmost frequently used quality criteria used include accuracy completeness readability design disclosures references provided fiftyfive studies 70 concluded quality problem web 17 22 remained neutral 7 studies 9 came positive conclusion positive studies scored significantly lower search p 02 evaluation p 04 methodsdue differences study methods rigor quality criteria study population topic chosen study results conclusions healthrelated web sites vary widely operational definitions quality criteria needed