Developing a core outcome set for sciatica: a scoping review of outcome measures

Objectives

Outcome measures used in sciatica research lack standardisation, making it difficult to combine data for analysis. This scoping review identified and categorised Patient Reported Outcome Measures (PROMs) employed in randomised controlled trials investigating sciatica interventions, providing a foundation for developing a consensus-based core outcome set.

Design Scoping review.

Data sources

A systematic search was conducted across MEDLINE, Embase and Cochrane Central for research published between 1999 and 2024.

Eligibility criteria

We included randomised controlled trials that involved patients with sciatica and used at least one PROM.

Data extraction and synthesis

Screening and data extraction were performed independently by at least two reviewers. PROMs were categorised using the OMERACT Filter 2.0 framework, inductively sub-categorised into domains, and then the frequency was counted to identify patterns of use. Collection time points and intervention type were also assessed.

Results

187 studies met the inclusion criteria. These studies employed 69 different PROMs, collected 548 times across all papers. The Visual Analogue Scale for pain (n=115), Oswestry Disability Index (n=109) and Numeric Pain Rating Scale (n=74) were most frequently used. PROMs predominantly addressed the pathophysiological (n=274) and life impact (n=262) domains, with minimal attention to resource use/economic impact (n=12). Injection-based interventions were the most studied treatment approach. Follow-up periods using the same PROMs varied considerably between studies, with trends by intervention type.

Conclusions

This review identified and categorised PROMs from numerous research studies, revealing substantial heterogeneity in outcome measurement for sciatica trials. This demonstrates the need for a standardised core outcome set. The predominance of use of non-sciatica-specific pain and disability measures suggests potential gaps in capturing sciatica-specific outcomes. Inconsistent follow-up durations and administration methods further highlight the requirement for standardisation.