Background & Aims

Interdisciplinary pain rehabilitation is a promising approach for many patients suffering from chronic pain, but not all see improvement. A model predicting health outcomes after interdisciplinary pain rehabilitation could improve targeting of treatment. The aim of this study was to demonstrate a modelling approach capable of predicting change simultaneously in several health measures, after interdisciplinary pain rehabilitation programs, using predictors before treatment. The model should explicitly model estimation and prediction uncertainty. The model could be implemented as a support tool when selecting patients to be included in pain rehabilitation programs.

Methods

Five outcome measures for chronic pain patients were selected, in accordance with the literature: SF-36 mental and physical component summaries, pain intensity during the past week (NRS), and the HADS anxiety and depression subscales . The predictive model was based on multivariate Bayesian linear regression. The multivariate approach reduces estimation uncertainty in the outcomes. The Bayesian method allows for explicit modeling of prediction uncertainty. This as predictions are given as predictive distributions rather than point predictions of change. A posterior predictive distribution describes the probabilities of different outcomes for some patient according to the model, accounting for the uncertainty regarding model parameters.

A study sample of 8168 individuals from the Swedish Quality Registry for Pain Rehabilitation was used in estimation. Model predictors were selected by a stepwise procedure comparing model AIC across different sets of predictors.

Results

Several models with different amounts of covariates were created. The most important covariates were baseline levels for all outcomes, but predictive performance improved for models including more covariates. Posterior predictive distributions of outcomes were created for several subjects, demonstrating the model’s ability to generate interpretable output that takes uncertainty into account and to account for several outcome dimensions simultaneously.

Conclusions

This study demonstrates a multivariate modeling approach for predicting several important health outcomes after interdisciplinary pain rehabilitation. The model explicitly accounts for uncertainty in estimation and prediction and can produce a probability distribution for the health outcomes of a patient, in addition to a single predicted most likely value. Such a model could be an important tool in patient selection for interdisciplinary pain rehabilitation and for communicating with patients regarding likely outcomes of rehabilitation.

References

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Presenting Author

Rode Grönkvist

Poster Authors

Rode Grönkvist, MSc

MSc

Inst of Medicine, Sahlgrenska Academy, Gothenburg University

Lead Author

Linda Vixner

PhD

University of Dalarna

Lead Author

Björn Äng

Dalarna University

Lead Author

Anna Grimby

School of Public Health and Community Medicine, Department of Med., Gothenburg Univ

Lead Author

Topics

  • Evidence, Clinical Trials, Systematic Review, Guidelines, and Implementation Science