1Higgins JPT, Green S. Cochrane handbook for systematic reviews of interventions 4.2.6[updated September 2006 ]. http ://www. cochrane. org/resources/handbook/hbook.htm.
2Rosenthal R. Statistically describing and combing studies. In : Cooper H, Hedges LV. The handbook of research synthesis. New York: Russell Sage Foundation, 1994:231-244.
3徐天和,主编.中国医学统计百科全书:多元统计分册.北京:人民卫生出版社,2003:69-74.
4Hedges LV. Statistical considerations. In: Cooper H, Hedges LV. The Handbook of Research Synthesis. New York: Russell Sage Foundation, 1994,30-33.
