How useful is a prognostic model for predicting different outcomes of neck pain?  

Pain, disability and a generally reduced quality of life are common consequences of musculoskeletal disorders. Prognostic models have been developed to help predict patient courses, but most prognostic studies include only one outcome, and it is not known whether the same prognostic model can predict different measures of how affected the patient is. As patients may pursue treatment goals related to various consequences of MSK disorders, including pain, function, and quality of life, clinicians should know the extent to which prognostic factors and prognostic models relate to each outcome.

In a Norwegian study, a group of researchers investigated how the predictions of a prognostic model differed across the outcomes pain intensity, functional impairment and quality of life.

The researchers conducted an observational, prospective cohort study with data from patients aged 18-84 years with neck pain consulting Norwegian chiropractors, focusing on three different outcomes: pain intensity (Numeric Pain Rating Scale), Neck Disability Index (NDI) and health-related quality of life (EQ- 5D). Associations between changes in outcome scores at 12-week follow-up were used to explore differences in explained variance and association between predictors and outcomes.

1313 patients participated in the study. Of these, 941 (72%) completed follow-up at 12 weeks. When the same prediction model was applied to different outcome measures, NDI was the most accurately predicted measure, while pain intensity was the least reliably predicted. The results point to a need for more knowledge about reasons why different effect measures can be predicted with different precision.

Myhrvold BL, Kongsted A, Irgens P, Robinson HS, Vøllestad NK. The association between different outcome measures and prognostic factors in patients with neck pain: a cohort study.
BMC Musculoskeletal Disorders. 2022