Minimal clinically important difference of the Four Square Step Test in people with degenerative spinal conditions.

OBJECTIVE: To identify the minimal clinically important difference (MCID) in the Four Square Step Test (FSST) for patients with degenerative spinal conditions before and after a six-week group-based physiotherapy programme. DESIGN: Secondary analysis of a longitudinal cohort study. SETTING: Physiotherapy department within a specialised orthopaedic hospital in the UK. PARTICIPANTS: Men and women with degenerative spinal conditions. INTERVENTIONS: All participants had a routine care package of up to six group-based physiotherapy led exercise and education sessions. MAIN OUTCOME MEASURES: An anchor-based approach using a self-report outcome measure (Activities-specific Balance Confidence [ABC] Scale) was utilised as a comparator to determine the MCID of the FSST. The MCID for the FSST was calculated as the difference in mean change scores from those who improved on the ABC Scale against those who did not improve (based on the standard error of measurement of the ABC Scale). RESULTS: Twenty-eight participants with degenerative spinal conditions (19 female) had a mean age of 73 years (SD 7.7). The mean ABC Scale scores for the whole sample were 61% (SD 19.1) at baseline and 66% (SD 18.3) post-physiotherapy. The mean FSST scores for the whole sample were 19.1seconds (SD 9.8) at baseline and 13.9seconds (SD 6.3) post-physiotherapy. The MCID for the FSST was 3.6seconds. CONCLUSIONS: The MCID for improvement in balance was 3.6seconds, indicating people with degenerative spinal conditions are likely to perceive an improvement of ≥3.6seconds in their FSST score as an important change in their balance performance and confidence.

The reliability and validity of the Figure of 8 Walk test in older people with knee replacement: does the setting have an impact?

OBJECTIVE: To determine the reliability and validity of the Figure of 8 Walk test (F8W) for older people after knee replacement surgery in the home setting. DESIGN: Observational repeated measures. SETTING: A specialist orthopaedic hospital and participants homes. PARTICIPANTS: Seventy-four older adults aged over 55 years one year following knee replacement surgery participated in two assessments more than one week apart. MAIN OUTCOME MEASURE: The time to complete, steps, boundary limits and smoothness score from the Figure of 8 Walk test (F8W), the time to complete the Timed Up and Go (TUG) test and the time to complete the Timed Walk Test (TWT). RESULTS: Overall, on 95% of occasions, the difference between the measurements for intra-rater reliability were within 1.8second of the two test times. The difference between the measurements for inter-rater reliability were found to be narrower than for intra-rater reliability with scores within 1.2second overall on 95% of occasions. The time to perform the F8W was highly correlated to the Timed Up and Go (overall sample r=0.921) and the variability spread within narrow limits (-0.8 to 0.8 z-scores). This was also true for the Timed Walk Test (overall sample r=0.834) with a narrow limit of variability on almost all of the observations (-1.16 to 1.16 z-scores). CONCLUSIONS: The F8W test has good reliability and validity when used in either a clinical or home setting for patients around one year following knee replacement surgery.