Minimal clinically important difference of Gait Assessment and Intervention Tool (GAIT) in patients with sub-acute stroke

BACKGROUND: The Gait Assessment and Intervention Tool (GAIT) is a well-accepted tool to determine gait characteristics in neurological patients. AIM: The aim of this study was to determine the minimal clinically importance difference (MCID) of the GAIT in sub-acute stroke patients. DESIGN: Prospective study. SETTING: An in-and out-patient rehabilitation clinic in a university hospital in Thailand. POPULATION: Patients with sub-acute stroke who had an ongoing rehabilitation between October 2017 to March 2019. METHODS: We used an anchor-based method to determine change in GAIT score needed to achieve MCID. Participants were dichotomized to `no change group' or `positive change group' based on different anchors of objective and subjective perceived changes in gait function after 4 weeks of rehabilitation. The groups were determined based on whether 1) participants achieved an increase in comfortable gait speed (CGS) of 2 0.06 m/s, 2) averaged Global Rating of Change (GROC) score was 2+3 evaluated by two physiatrists 3) GROC score of was 2+3 rated by the participants. The best cut-off point was the score which most successfully separated these two groups within the ROC curve. RESULTS: Thirty-one participants with sub-acute stroke (18 males, 13 female) completed both assessments. Their average age was 60.3 +/- 11.4 years. The best cut-off point were a 2.5-and 4-point improvements in GAIT score based on changes in CGS (AUC 0.76, 95% CI 0.58-0.95) and clinicians' perceived changes (AUC 0.88, 95% CI 0.76-1.00). Additionally, the best cut-off point was 1.5 (AUC 0.71 95% CI 0.31-1.00) when determined by participants' perception. All anchors yielded adequate discriminative ability. The positive likelihood ratio (LR) was in the range of 2.7-5.5 and the negative LR range was 0.1-0.3. CONCLUSIONS: A change in GAIT score should exceed 1.5, 2.5 and 4 to be considered MCID based on participants' GROC, CGS and Clinicians' GROC anchors. CLINICAL REHABILITATION IMPACT: This information will be useful for the determination of changes after rehabilitation and for tracking sub-acute stroke patients' progress.