Objectives Participation in organized activities is related with a range of positive outcomes, but the way such participation is measured has not been scrutinized. Test-retest reliability as an important indicator of a scale's reliability has been assessed rarely and for "The scale of participation in organized activities'' lacks completely. This test-retest study is based on the Health Behaviour in School-aged Children study and is consistent with its methodology.
Methods We obtained data from 353 Czech (51.9 % boys) and 227 Slovak (52.9 % boys) primary school pupils, grades five and nine, who participated in this study in 2013. We used Cohen's kappa statistic and single measures of the intraclass correlation coefficient to estimate the test-retest reliability of all selected items in the sample, stratified by gender, age and country.
Results We mostly observed a large correlation between the test and retest in all of the examined variables (kappa ranged from 0.46 to 0.68). Test-retest reliability of the sum score of individual items showed substantial agreement (ICC = 0.64).
Conclusions The scale of participation in organized activities has an acceptable level of agreement, indicating good reliability.