Get access

Reporting outcomes of back pain trials: A modified Delphi study


Tel.: +44 (0)207 882 2520; fax: +44 (0)207 882 2552.


Background: Low back pain is a common and expensive health complaint. Many low back pain trials have been conducted, but these are reported in a variety of ways and are often difficult to interpret.

Aim: To facilitate consensus on a statement recommending reporting methods for future low back pain trials.

Methods: We presented experts with clinicians’ views on different reporting methods and asked them to rate and comment on the suitability reporting methods for inclusion in a standardized set. Panellists developed a statement of recommendation over three online rounds. We used a modified Delphi process and the RAND/UCLA appropriateness method as a formal framework for establishing appropriateness and quantifying panel disagreement.

Results: A group of 63 experts from 14 countries participated. Consensus was reached on a statement recommending that the continuous patient-reported outcomes commonly used in back pain trials, are reported using between-group mean differences (accompanied by minimally important difference (between-group/population-level) thresholds where these exist), the proportion of participants improving and deteriorating according to established and relevant minimally important change thresholds, and the number needed to treat; all with 95% confidence intervals. Outcomes may additionally be reported using alternative approaches (e.g. relative risks, odds ratios, or standardized mean difference) according to the needs of a particular trial.

Conclusions: A group of back pain experts reached a high level of consensus on a statement recommending reporting methods for patient-reported outcomes in future low back pain trials. The statement has the potential to increase interpretability and improve patient care.