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 ≥ 0.06 m/s, 2) averaged Global Rating of Change (GROC) score was ≥+3 evaluated by two physiatrists 3) GROC score of was ≥+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.