[Comparison of two screening questionnaires for patients with low back pain. Collation of risk factors for chronification].

BACKGROUND

Screening for risk factors for chronic low back pain (LBP) (yellow flags) is recommended by clinical guidelines. Various questionnaires to assess yellow flags have been proposed.

OBJECTIVE

The aim of this study was to compare the prognostic validity of two screening questionnaires.

METHODS

This was a prospective observational study with 241 LBP patients from 9 general practitioners, 4 orthopedic surgeons and 2 pain clinics. We compared the Örebro musculoskeletal pain questionnaire (ÖMSPQ) and the Heidelberg short questionnaire (HKF-R10) which were completed by all patients at inclusion before the consultation. Primary outcomes were assessed after 3 months by mail. Clinical endpoints were pain intensity, disability and more than two follow-up consultations.

RESULTS

The sensitivity of the HKF-R10 to predict the primary outcome ranged from 81 % to 88 %, while the specificity was much lower (37-47 %). The ÖMSPQ showed an opposite pattern with a low sensitivity ranging from 50 % to 58 % but a higher specificity (77-80 %). In patients initially classified as having chronic LBP (n = 81), using the questionnaires as a diagnostic tool, the sensitivity of both questionnaires increased but specificity decreased. Single items may perform better with regard to primary outcome than the sum scores.

CONCLUSIONS

Both screening questionnaires for chronic LBP have insufficient diagnostic and prognostic validity for routine use in ambulatory care. Further studies are needed to improve diagnostic and prognostic validity and to elaborate criteria for a targeted use of screening questionnaires to guide therapeutic interventions.