{
  "abstract": "Objectives The objective was to develop, internally and externally validate a prognostic model for symptom dissatisfaction, assessed by the patient acceptable symptom state (PASS), for older adults (≥55 years) seeking primary care for a new episode of back pain.Design Development, internal and external validation of a prognostic model using data from two prospective cohort studies with a 1-year follow-up was conducted.Participants and setting The Norwegian cohort (n=452) was used for model development and internal validation. External validation was conducted using the Dutch cohort (n=675).Outcome measures and method The outcome was defined as symptom dissatisfaction based on the PASS at 12 months follow-up. A logistic regression model was developed using backward selection and internally validated using 200 bootstrap samples. External validation included recalibration of the model intercept and slope. Model performance was measured using Nagelkerke-R 2, area under the curve (AUC) and calibration slope, calibration in-the-large (CITL) and calibration plots.Results At 12 months, ~55% reported dissatisfaction in both cohorts. The final model included disability, catastrophising, recent back pain episode, spinal rotation pain, baseline symptom satisfaction, symptom duration and recovery expectation as predictors. The internally validated model showed acceptable discrimination (AUC 0.75, 95% CI 0.71 to 0.78), R 2 was 0.23, the calibration slope and CITL being 0.89 (95% CI 0.73 to 1.08) and 0.01 (95% CI −0.16 to 0.15), respectively. External validation performance after recalibration yielded AUC 0.68 (95% CI 0.65 to 0.70), slope 0.86 (95% CI 0.67 to 1.05) and CITL 0.08 (95% CI −0.01 to 0.16).Conclusions This prognostic model could be a useful tool for predicting PASS outcomes among older adults with back pain. The external validation results imply that more research is needed to optimise predictions.Trial registration number NCT04261309.",
  "authors": [
    {
      "affiliations": [
        "Department of Rehabilitation Science and Health Technology, Oslo Metropolitan University, Oslo, Norway",
        "Department of Research and Development in Mental Health, Akershus University Hospital, Lørenskog, Norway"
      ],
      "name": "Ann-Christin Sannes"
    },
    {
      "affiliations": [
        "Department of General Practice, Erasmus MC University Medical Centre, Rotterdam, The Netherlands",
        "Provincial Agency for Health of the Autonomous Province of Trento, Trento, Italy"
      ],
      "name": "Daniel Feller"
    },
    {
      "affiliations": [
        "Department of Rehabilitation Science and Health Technology, Oslo Metropolitan University, Oslo, Norway",
        "Oslo University Hospital, Oslo, Norway"
      ],
      "name": "Are Hugo Pripp"
    },
    {
      "affiliations": [
        "Department of General Practice, Erasmus MC University Medical Centre, Rotterdam, The Netherlands"
      ],
      "name": "Alessandro Chiarotto"
    },
    {
      "affiliations": [
        "Department of Rehabilitation Science and Health Technology, Oslo Metropolitan University, Oslo, Norway"
      ],
      "name": "Lise Kretz Grøndahl"
    },
    {
      "affiliations": [
        "Department of Rehabilitation Science and Health Technology, Oslo Metropolitan University, Oslo, Norway"
      ],
      "name": "Rikke Munk Killingmo"
    },
    {
      "affiliations": [
        "IMM Institute of Environmental Medicine, Karolinska Institute, Stockholm, Sweden"
      ],
      "name": "Iben Axén"
    },
    {
      "affiliations": [
        "Department of Rehabilitation Science and Health Technology, Oslo Metropolitan University, Oslo, Norway",
        "Oslo University Hospital, Oslo, Norway"
      ],
      "name": "Kjersti Storheim"
    },
    {
      "affiliations": [
        "Department of Rehabilitation Science and Health Technology, Oslo Metropolitan University, Oslo, Norway",
        "Department of Research and Communication Unit for Musculoskeletal Health, Oslo universitetssykehus Ulleval, Oslo, Norway"
      ],
      "name": "Margreth Grotle"
    },
    {
      "affiliations": [
        "Department of Rehabilitation Science and Health Technology, Oslo Metropolitan University, Oslo, Norway"
      ],
      "name": "Ørjan Nesse Vigdal"
    }
  ],
  "title": "Development, internal and external validation of a prognostic model for symptom dissatisfaction among older adults with a new episode of back pain",
  "uid": "917b5ee7-df58-5d6b-9821-6eb35485d24e"
}