Minimum important difference for the incremental shuttle walk test in long covid rehabilitation.

The minimum important difference (MID) for the incremental shuttle walk test (ISWT) in individuals with long covid was estimated using anchor-based and distribution-based methods. 397 participants (56 ± 13 years; 63.7% male) with long covid completed a 6-week rehabilitation programme and rated perceived change using the Global Rating of Change Scale (GRCS). Change in ISWT distance differed across GCRS categories (p<0.05); participants reporting slight improvement increased ISWT distance by 60.7±85.9 m. Receiver operating characteristic analysis identified an optimal cut-off of 35 m (area under the curve 0.70, 95% CI 0.61 to 0.79; p<0.05). Distribution-based methods yielded MID estimates of 40.1 m and 52.5 m, supporting an MID range of 35-60.7 m.