How many patients? How many limbs? Analysis of patients or limbs in the orthopaedic literature: Asystematic review

被引:130
作者
Bryant, D
Havey, TC
Roberts, R
Guyatt, G
机构
[1] Univ Western Ontario, Fac Hlth Sci, London, ON N6G 1H1, Canada
[2] McMaster Univ, Fac Hlth Sci, Michael G DeGroote Ctr Learning & Discovery, Hamilton, ON L8N 3Z5, Canada
[3] McMaster Univ, Hamilton Civ Hosp, Res Ctr, Fac Hlth Sci,Clin Epidemiol & Biostat, Hamilton, ON L8V 1C3, Canada
关键词
D O I
10.2106/JBJS.E.00272
中图分类号
R826.8 [整形外科学]; R782.2 [口腔颌面部整形外科学]; R726.2 [小儿整形外科学]; R62 [整形外科学(修复外科学)];
学科分类号
摘要
Background: Clinical studies assessing orthopaedic interventions often include data from two limbs or multiple joints within single individuals. Without appropriate design or statistical approaches to address within-individual correlations, this practice may contribute to false precision and possible bias in estimates of treatment effect. We conducted a systematic review of the orthopaedic literature to determine the frequency of inappropriate inclusion of nonindependent limb or joint observations in clinical studies. Methods: We identified seven orthopaedic journals with high Science Citation Index impact factors and retrieved all clinical studies for 2003 for any intervention on any limb or joint. Results: We identified 288 clinical studies, 143 of which involved two limbs or multiple joint observations from single individuals. These studies included nineteen randomized clinical trials (13%) fifty-eight two-group cohort studies (41%), and sixty-six one-group cohort studies (46%). Seventy-six (53%) of the 143 studies involved statistical comparisons between patient groups with use of tests of association, and an additional sixty studies (42%) presented estimates of proportions without statistical comparisons. Only sixteen of the seventy-six studies involving statistical comparisons involved the use of any technique or methodological approach to account for multiple, nonindependent observations. A median of approximately 13% of the patients in these studies contributed more than one observation. The median proportion of nonindependent observations to total observations (the unit of analysis) was approximately 23%. Conclusions: Our findings suggest that a high proportion (42%) of clinical studies in high-impact-factor orthopaedic journals involve the inappropriate use of multiple observations from single individuals, potentially biasing results. Orthopaedic researchers should attend to this issue when reporting results.
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页码:41 / 45
页数:5
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