European Spine Journal

, 18:1858

What is an acceptable outcome of treatment before it begins? Methodological considerations and implications for patients with chronic low back pain

Authors

    • Clinical Locomotion Science, Institute for Sports Science and Clinical BiomechanicsUniversity of Southern Denmark
  • Claus Manniche
    • Backcenter Funen, Part of Clinical Locomotion Science
  • Lars Korsholm
    • Clinical Locomotion Science, Institute for Sports Science and Clinical BiomechanicsUniversity of Southern Denmark
    • Department of StatisticsUniversity of Southern Denmark
  • Niels Grunnet-Nilsson
    • Clinical Locomotion Science, Institute for Sports Science and Clinical BiomechanicsUniversity of Southern Denmark
  • Jan Hartvigsen
    • Clinical Locomotion Science, Institute for Sports Science and Clinical BiomechanicsUniversity of Southern Denmark
    • Nordic Institute of Chiropractic and Clinical Biomechanics, Part of Clinical Locomotion Science
Original Article

DOI: 10.1007/s00586-009-1070-1

Cite this article as:
Lauridsen, H.H., Manniche, C., Korsholm, L. et al. Eur Spine J (2009) 18: 1858. doi:10.1007/s00586-009-1070-1

Abstract

Understanding changes in patient-reported outcomes is indispensable for interpretation of results from clinical studies. As a consequence the term “minimal clinically important difference” (MCID) was coined in the late 1980s to ease classification of patients into improved, not changed or deteriorated. Several methodological categories have been developed determining the MCID, however, all are subject to weaknesses or biases reducing the validity of the reported MCID. The objective of this study was to determine the reproducibility and validity of a novel method for estimating low back pain (LBP) patients’ view of an acceptable change (MCIDpre) before treatment begins. One-hundred and forty-seven patients with chronic LBP were recruited from an out-patient hospital back pain unit and followed over an 8-week period. Original and modified versions of the Oswestry disability index (ODI), Bournemouth questionnaire (BQ) and numeric pain rating scale (NRSpain) were filled in at baseline. The modified questionnaires determined what the patient considered an acceptable post-treatment outcome which allowed us to calculate the MCIDpre. Concurrent comparisons between the MCIDpre, instrument measurement error and a retrospective approach of establishing the minimal clinically important difference (MCIDpost) were made. The results showed the prospective acceptable outcome method scores to have acceptable reproducibility outside measurement error. MCIDpre was 4.5 larger for the ODI and 1.5 times larger for BQ and NRSpain compared to the MCIDpost. Furthermore, MCIDpre and patients post-treatment acceptable change was almost equal for the NRSpain but not for the ODI and BQ. In conclusion, chronic LBP patients have a reasonably realistic idea of an acceptable change in pain, but probably an overly optimistic view of changes in functional and psychological/affective domains before treatment begins.

Keywords

Minimal clinically important difference (MCID)RetrospectiveProspectivePatient-reported outcomeClinical change

Copyright information

© Springer-Verlag 2009