2Grimes DA,Schulz KF.An overview of clinical research:the lay of the land[J].Lancet,2002,359(9300):57-61.
3Egger M,Smith GD,Altman DG.Systematic reviews in health care.Meta-analysis in context[M].2nd ed.London:BMJ Publishing Group,BMA House,Tavistock Square,WC1H 9JR,2001.
4Stang A.Critical evaluation of the Newcastle-Ottawa scale for the assessment of the quality of nonrandomized studies in metaanalyses[J].Eur J Epidemiol,2010,25(9):603-5.
5Wells GA,Shea B,O'Connell D,et al.The Newcastle-Ottawa Scale (NOS) for assessing the quality if nonrandomized studies in metaanalyses[EB/OL].[2012-06-15].http://www.ohri.ca/programs/clinical_epidemiology/oxford.htm.
7Wells G,Shea B,O'Connell D,et al.NewCastle–Ottawa Quallty Assessment Scale--Case Control Studies[EB/OL].[2012-06-15].http://www.ohri.ca/programs/clinical_epidemiology/oxford.asp.
8Ibbotson T,Grimshaw J,Grant A.Evaluation of a programme of workshops for promoting the teaching of critical appraisal skills[J].Med Educ,1998,32(5):486-91.