Low-back pain definitions in occupational studies were categorized for a meta-analysis using Delphi consensus methods.

OBJECTIVE To determine which literature-based definitions of low back pain (LBP) could be combined to produce sufficiently similar sets for use in a meta-analysis. STUDY DESIGN AND SETTING A group of six international experts participated in an e-mail-administered Delphi process. Literature-based LBP definitions were preliminarily classified into 14 sets within four outcome types: pathology, symptoms and care-seeking, functional limitations, and participation. Experts independently rated their level of agreement that each outcome definition belonged in its assigned set using a seven-point Likert scale. After each round, results were synthesized and revised classifications were fed back to the experts who were asked to consider them before rerating the outcome definitions. RESULTS The experts completed three Delphi rounds and reached consensus on the categorization of 115/119 (97%) of the outcome definitions. There were 20 final sets of outcomes identified: three sets of pathology outcomes, two sets each of functional limitation and participation outcomes, and 13 sets of symptom and care-seeking outcomes. CONCLUSIONS In a research area that currently lacks uniformly accepted definitions of outcomes, we successfully used a Delphi consensus process to reach substantial agreement on combinable LBP outcomes that would be combinable for a meta-analysis.