Article type
Year
Abstract
Background: Several recent systematic reviews of low back pain prognosis and prognostic factors have recently been published, however, they have used different methods and have often reached inconsistent conclusions.
Objectives: To identify, describe and synthesize systematic reviews of low back pain prognosis, and explore the impact of differences in the reviews' methods.
Methods: Reviews identified in MEDLINE, and EMBASE, CINAHL and HealthStar (up to January 2007) using a comprehensive strategy for prognosis studies, low back pain, and broad search terms for systematic reviews, plus supplemental sources. We identified and included 15 systematic reviews of low back pain prognosis studies published between 2000 and 2005. One reviewer extracted and a second checked review characteristics and results. Two reviewers independently assessed review quality.
Results: Review questions and selection criteria varied and there were both focused and broad reviews of prognostic factors. A quarter of reviews did not clearly define search strategies. The number of potential citations identified ranged from 15 to 4458 and the number of included prognosis studies ranged from 3 to 32 (of 145 distinct citations identified across the reviews). Two-thirds of reviews assessed quality of included studies, however assessed only a median of 3.5 of 6 potential biases. Information on prognostic factors was grouped in different ways. All reviews reported associations based on statistical significance, but used various strategies for syntheses. Six reviews were at high risk of at least one potential source of bias. A small number of prognostic factors were consistently reported to be associated with longer disability in 7 reviews of the same scope, however, we also found discrepancies in the number and types of studies included and in conclusions.
Conclusions: There is an immediate need for methodological work in the area of prognosis systematic reviews. We observed the impact of different methods on the results of systematic reviews in the area of low back pain prognosis. Because of methodological shortcomings in the primary and review literature, there remains uncertainty about potential biases.
Objectives: To identify, describe and synthesize systematic reviews of low back pain prognosis, and explore the impact of differences in the reviews' methods.
Methods: Reviews identified in MEDLINE, and EMBASE, CINAHL and HealthStar (up to January 2007) using a comprehensive strategy for prognosis studies, low back pain, and broad search terms for systematic reviews, plus supplemental sources. We identified and included 15 systematic reviews of low back pain prognosis studies published between 2000 and 2005. One reviewer extracted and a second checked review characteristics and results. Two reviewers independently assessed review quality.
Results: Review questions and selection criteria varied and there were both focused and broad reviews of prognostic factors. A quarter of reviews did not clearly define search strategies. The number of potential citations identified ranged from 15 to 4458 and the number of included prognosis studies ranged from 3 to 32 (of 145 distinct citations identified across the reviews). Two-thirds of reviews assessed quality of included studies, however assessed only a median of 3.5 of 6 potential biases. Information on prognostic factors was grouped in different ways. All reviews reported associations based on statistical significance, but used various strategies for syntheses. Six reviews were at high risk of at least one potential source of bias. A small number of prognostic factors were consistently reported to be associated with longer disability in 7 reviews of the same scope, however, we also found discrepancies in the number and types of studies included and in conclusions.
Conclusions: There is an immediate need for methodological work in the area of prognosis systematic reviews. We observed the impact of different methods on the results of systematic reviews in the area of low back pain prognosis. Because of methodological shortcomings in the primary and review literature, there remains uncertainty about potential biases.