Validation of shuttle tests in children with cystic fibrosis

Abstract

Shuttle tests are simple, inexpensive field tests that have been used to estimate the cardiorespiratory status of children. It has yet to be validated in children with CF. The aim of this study was to assess the reproducibility and criterion validity of shuttle tests in children with cystic fibrosis (CF). Ninety-three CF patients aged 6 to 16 years of age with a wide range of disease severity performed the study. The 10-m shuttle test was used for children 7 years of age and younger and those deemed too chronically ill by their physicians to perform the longer test (n = 35.) All other children performed the 20-m shuttle test (n = 58). Reproducibility and criterion validity were assessed for each child over a two week period. Gas analysis was performed throughout testing using a polargraphic gas analyzer. The 10-m shuttle tests were reproducible (mean difference between tests VO(2) 2.41 mL/kg/min, CI 3.46,-0.18) and the difference from treadmill testing was not statistically significant (mean difference VO(2) 5.30 mL/kg/min, CI-7.46, 1.18). The 20-m shuttle tests were reproducible (mean difference between tests VO(2) 2.07 mL/kg/min, CI-3.90,0.60) and the difference from treadmill testing was not statistically significant (mean difference VO(2) 3.50 mL/kg/min, CI-4.90, 1.60). We conclude that when formal exercise testing with treadmill or cycle ergometer cannot be performed, the shuttle tests provide a reproducible and valid alternative.

Recommendations on the use of exercise testing in clinical practice

“…[212] compared a 3-min step test with a 6-MWT and found both useful in the assessment of exercise tolerance in children with CF, whereas SELVADURAI et al [213] and POUESSEL et al [214] validated a shuttle test in CF children and found this a useful test.…”

The Physiotherapist's Use of Exercise in the Management of Young People with Cystic Fibrosis

“…The modified shuttle walk test as described by Selvadurai et al (2003) is a symptom-limited exercise test, in which the participant moves from end to end of a 10m course in time with the 'beeps' from a pre-recorded tape. This test is valid in young people with CF (Cox et al, 2006), sensitive to change after hospitalization (Bradley et al, 1999(Bradley et al, , 2000 and correlates with VO 2 max (Rogers et al, 2003).…”

“…It detects improvement in exercise capacity following hospitalization (Pike et al, 2001), but its use may be limited in those with well preserved lung function and fitness levels due to a potential ceiling effect (Selvadurai et al, 2003). It is also clear that actual workload will vary according to step height and weight and height of the participant (Selvadurai et al, 2003).…”

“…These can be undertaken outside of formal testing laboratories which may promote a less stressful environment for the young person (Cox et al, 2006) and some are useful in the research context where portable tools can provide follow-up information without the need for repeated visits to hospital facilities. Further, there is some evidence that young people with CF prefer field tests to formal exercise tests (Selvadurai et al, 2003). However, it is important to recognize that some information which is detected by more complex exercise tests may be missed by simple field tests (Narang et al, 2003).…”

Physical Activity Levels and Performance in Italian Adolescents with Cystic Fibrosis: A Multicenter Cross-sectional Study

“…Physical performance: Performance was assessed using the Incremental Shuttle Walk Test (ISWT) that is a validated field test of exercise tolerance in CF in which participants walk 10 m lengths at progressively increasing paces [17]. The number of completed shuttles and ISWT distance (ISWD) recorded and used to express exercise tolerance.…”