Reliability and validity of the incremental shuttle walking test in individuals after stroke
Ludmylla Ferreira Quintino1, Larissa Tavares Aguiar1, Sherindan Ayessa Ferreira de Brito1
1Department of Physiotherapy, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
Background:
There are limitations to perform the cardiopulmonary exercise test (CPET) and the six-minute walking test (6MWT) in clinical settings. The incremental shuttle walking test (ISWT) might be an alternative assessment of exercise capacity and an estimation of cardiopulmonary fitness after stroke.
Objectives:
To investigate the test-retest and inter-rater reliabilities, the standard error of measurement (SEM) and the minimal detectable change (MDC) of the ISWT, its construct validity to assess exercise capacity and its concurrent validity to estimate cardiopulmonary fitness after stroke.
Methods:
Prospective diagnostic accuracy study. Fifty-one individuals (54 ± 11 years) at the chronic phase (65 ± 73 months after stroke) were included. The distance walked, in meters, during the 12-stage-ISWT and the 6MWT and the peak oxygen uptake (VO2peak, ml.kg-1.min-1) in the CPET (gold standard) were assessed.
Results:
Significant and high to very high magnitude test-retest and inter-rater reliabilities (0.88≤ICC≤0.93) of the ISWT was found. The SEM for both reliabilities was small (-23.35 m≤ SEM≤41.47 m). The MDC for test-retest and inter-rater reliabilities were 114.63 m and 64.53 m, respectively. For construct validity, a significant and high magnitude correlation between the ISWT and the 6MWT was found (ICC = 0.82). For the concurrent validity, a significant, but low magnitude correlation was found between the ISWT and the VO2peak (rho = 0.42).
Conclusions:
The ISWT demonstrated adequate reliabilities and construct validity for exercise capacity assessment. However, the concurrent validity of the ISWT as an estimation of cardiopulmonary fitness still requires further research.
