Methods & Results

The Steering Committee overseeing this project selected 17 potential core instruments for physical functioning, three for pain intensity, and five for HRQoL. Evidence on their measurement properties in nsLBP was synthesized in three systematic reviews using COSMIN methodology. Researchers, clinicians, and patients (n = 208) were invited in a Delphi survey to seek consensus on which instruments to endorse as core. Consensus was a-priori set at 67% of participants agreeing on endorsing an instrument. Two Delphi rounds were run (response rates = 44% and 41%). Agreement was reached on endorsing the Oswestry Disability Index (ODI 2.1a) for physical functioning, the Numeric Rating Scale (NRS) for pain intensity, but not on other instruments. Several participants demanded to have free of charge core instruments. Taking these results into account, the steering committee formulated the following recommendations: ODI 2.1a or 24-item Roland Morris Disability Questionnaire for physical functioning, NRS for pain intensity, Short-Form 12 or 10-item PROMIS Global Health for HRQoL.