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Pictorial and verbal category-ratio scales for effort estimation in children
B Marinov1, S Mandadjieva, S Kostianev
1Department of Pathophysiology, Medical University of Plovdiv, Plovdiv, Bulgaria. b_marinov@mail.orbitel.bg
Background:
Research on the diverse aspects of exercise performance in childhood in the past 20 years has included an increase in the study of perceived exertion.
Objective:
The aim of this study was to compare children's ratings of effort perception by means of the Borg Category-Ratio Perceived Exertion (CR-10) Scale and a pictorial version of the Children's Effort Rating Table (Pictorial-CERT) scale, and to assess the long-term repeatability of the two scales.
Methods:
Fifty healthy children (25 girls and 25 boys; initially aged 10.4 +/- 0.5 years) participated in three incremental treadmill tests until volitional exhaustion or a maximal gradient of 22% at 5.4 km/h was attained. The first two tests (T1 and T2) were at an interval of 1 month. The third test (T3) took place 3 years later and utilized exactly the same protocol.
Results:
Perceived exertion correlated significantly with measures of exercise intensity - minute ventilation, heart rate and oxygen uptake for the whole group. The range of correlations for all tests was significantly higher for the Pictorial-CERT (r = 0.62-0.88 and r = 0.59-0.71 for the Pictorial-CERT and CR-10 respectively). Intraclass correlation coefficients between T1 and T2 were significantly higher for the Pictorial-CERT in comparison with the CR-10 (0.77 vs. 0.54, respectively; z = -2.07; P = 0.038).
Conclusion:
The Pictorial-CERT is more appropriate for use with children of this age range and appears to be more reproducible than the Borg CR-10 Scale. Concurrent and construct validity evidence promotes the use of the Pictorial-CERT by junior children.
