This study was conducted to test the validity of the Pictorial Children's Effort Rating Table (PCERT) and OMNI walk/run scales.
Children (26 boys age 11.2 yr ± 1.6 and 25 girls age 11.1 yr ± 1.4) performed a five-stage incremental exertion treadmill test. The undifferentiated perceived exertion from the PCERT and OMNI scales was assessed for construct validity using Pearson correlations with O2 and heart rate as criteria and concurrent validity by correlating PCERT and OMNI scores.
Increases in PCERT and OMNI scale scores were correlated with increases in O2 (r = 0.90 and 0.92) and heart rate (r = 0.89 and 0.92). No difference was found in slope of the PCERT and OMNI scores when regressed against heart rate or O2 and the slopes were invariant across sexes. To test concurrent validity of the PCERT and OMNI scales, subject scores at each stage were converted to a percentage of the maximal scale. No effect of sex was noted on perceived exertion (P = 0.32), and the percentage of the maximal PCERT and OMNI scales was almost identical at each stage (P = 0.73).
Validity of both the PCERT and OMNI scales was established for submaximal exercise. PCERT and OMNI scores are not interchangeable because they have different scales, but at a given exercise intensity youth assign similar percentages of the maximal scores.
1Department of Pediatrics, School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY; 2Department of Exercise and Nutrition Sciences, University at Buffalo, Buffalo, NY; and 3Department of Social and Preventive Medicine, University at Buffalo, Buffalo, NY
Address for correspondence: James N. Roemmich, Ph.D., State University of New York at Buffalo, Department of Pediatrics, Farber Hall, Room G56, 3435 Main Street, Building #26, Buffalo, NY 14214-3000; E-mail: firstname.lastname@example.org.
Submitted for publication March 2005.
Accepted for publication October 2005.