Objective. - To assess the sensitivity to change of three algofunctional scales for neck pain.

Methods. - Observational, prospective study. Patients with neck disorders were included. Pain and patients' perceived handicap assessed on visual analogue scales (VAS Pain, VAS Handicap), and functional disability measures (Neck Disability Index, Neck Pain and Disability Scale, Northwick Park Neck Pain Questionnaire) were recorded twice, at baseline and at an 11-month follow-up assessment. Sensitivity to change was assessed using the effect size (ES) and the standardised response mean (SRM), and the non-parametric Spearman's rank correlation coefficient (r) was used to assess the correlation between quantitative variable changes and patients' overall opinion. Analysis of variance (ANOVA) followed by a Tukey-test was performed to determine if the scales distinguished improved, stable, and deteriorated patients.

Results. - Seventy-one patients (43 women, mean age 49 years) were included and evaluated twice at an interval of 11 ± 2 months. The three scales showed good sensitivity to change. The ANOVA showed a group effect, and individual changes in the scales scores were statistically different in two-by-two comparisons (improved, stable or deteriorated patients). Changes in NPDS scores had the highest correlation with patient's overall assessment (r = 0.592).

Conclusion. - The three scales can detect changes in patients with neck disorders. Changes in NPDS score had the best correlation with patients' overall opinion concerning their neck disorder and this questionnaire should be given preference in clinical trials.