Reliability of the National Program for Playground Safety (NPPS) Report Card
Playground injury has been recognized as an important issue in children’s everyday life. In order to analyze the factors that lead to an accident, researchers usually use questionnaires or report cards that have been used in other accident research areas. Reliable assessment tools have to be established in playground safety field. In the current study two researchers evaluated the reliability of the USA’s National Program for Playground Safety (NPPS) report card in 138 Greek public playgrounds throughout Greece.
Cronbach’s alpha (a) was applied in order to estimate the internal consistency of the form and for the total score was found to be .461. The inter-rater and the test-retest reliability of the evaluation form were determined by calculating the Kendall’s tau-b and the McNemar’s test. Coefficients were found .947 (p<.001) and .83 (p<.001) respectively. Also, the standard error of the measurement (SEM) was .443 and .385, the mean coefficient of variation (% CV) fluctuated between 0-23.6 (mean 2.02) and 0-20.2 (mean 1.23) respectively. BlandAltman plots demonstrated that the vast majority of the total scores were within two standard deviations for the two raters and the two measurements. NPPS appears to be a reliable report card for evaluating playground safety.