Comment on: A meta-analysis of common risk factors associated with the diagnosis of developmental dysplasia of the hip in newborns

摘要

With interest we read the review from Ortiz-Neira et al. on risk factors for hip dysplasia in newborns [1 ]. The aim of this study was to assess the magnitude of six predefined risk factors of developmental dysplasia of the hips (DDHs) and to calculate the prevalence rate of DDH. The authors precisely describe the selection criteria for studies to be included in the meta-analysis. However, we have some concerns about their study selection. First, at least two studies included in this meta-analysis report on children in a selected population (with a positive family history, breech presentation or abnormal findings at physical examination), which possibly masks the impact of risk factors [2,3]. Second, the authors have included three case-control studies, which invalidate their calculation of the prevalence of DDH which they have made in the last paragraph of the results [3-5]. This is especially worrisome as the calculation of the study populations in table one did not add up to the denominator mentioned in the results.