Description of studies

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Description of studies

Literature search

Study quality assessments, levels of evidence and grades of recommendation Recommendations are graded according to the overall level of evidence (LoE) on which the recommendations are based, which is determined by the quality and source of evidence: (Levels of evidence and grades of recommendation in PROSPECT reviews (from 2006)

Quantitative analyses

Overall, few meta-analyses could be performed that used data from more than two studies. This is because there are a limited number of studies of homogeneous design that report similar outcome measures. Therefore, the majority of the procedure-specific evidence was assessed only qualitatively.

Transferable evidence

Transferable evidence of analgesic efficacy from comparable procedures or evidence of other outcomes, such as adverse effects, has been included to support the procedure-specific evidence where this is insufficient to formulate the recommendations.

Many studies that were identified in the literature search included patients undergoing total knee or hip replacement and reported data pooled from all these patients. Such studies are excluded from the procedure-specific systematic review but have been used as additional transferable evidence where required. Data from other types of orthopaedic surgery (e.g. ACL reconstruction, spinal surgery, hip surgery) were not used for transferable evidence of analgesic efficacy in most instances because it was considered that the pain profile of these procedures was too different from that of TKA. However, data from studies in a variety of procedures have been used for evidence of adverse-effects, which can occur regardless of the procedure.