Understanding prognosis to improve rehabilitation: the example of lateral elbow pain
OBJECTIVE: A systematic overview of evidence aimed at determining the clinical course of lateral elbow pain and prognostic factors that affect elbow pain duration and outcomes. DATA SOURCES: Online bibliographic database searches from 1983 to 1994; information requests from selected authors and bibliography screenings. STUDY SELECTION: One author reviewed 424 articles; 40 met the following eligibility criteria: any study with primary data on soft tissue injuries specific to the elbow which referred to prognosis or reported use of any outcome measure. DATA ABSTRACTION: Strength of evidence grade based on clinical epidemiological validity assessment. Criteria included in the validity assessment included case definition, patient selection, follow-up, outcome, prognostic factors, and analysis. All eligible studies were independently assessed by two investigators. DATA SYNTHESIS: Four studies (10%) were judged to provide moderate strength of evidence; no studies were graded as providing strong evidence on prognosis. All four moderate-quality studies were clinical trials of short duration. One study indicated that site of lesion and prior occurrence may be predictive of poorer outcome in patients with lateral epicondylitis. CONCLUSION: The majority of studies on lateral elbow pain were limited by methodological weaknesses in selection and definition of the study population, length of follow-up, and analysis of prognostic factors. Estimates of duration were only available from weaker studies with longer follow-up times; significant subject heterogeneity in the weaker studies prevented a determination of usual clinical course. More methodologically rigorous research on prognosis could assist clinicians in patient care and evaluation of interventions