An international team of researchers compared YSR scores obtained by 7,137 11- to 18-year-olds in general population samples from 7 cultures. Differences in mean Total Problems scores yielded a small effect size (5% of variance) across the 7 cultures.
Slightly larger cross-cultural effects were found for some syndromes, while slightly smaller effects were found for other syndromes. The largest cross-cultural effect (8% of variance) was found for the Thought Problems syndrome, while the smallest cross-cultural effect (3% of variance) was found for the Aggressive Behavior syndrome. The highest mean Total Problems score was obtained by Chinese youths, while the lowest was obtained by Israeli youths.
For the Externalizing scale, the highest mean score was obtained by American youths, while the lowest was obtained by Turkish youths. Jamaican youths obtained the highest mean Internalizing score, while Israeli youths obtained the lowest. With no significant cross-cultural differences, boys obtained higher Externalizing scores but lower Internalizing scores than girls. Correlations between mean scores for specific problem items were highly significant between all pairs of cultures.
The correlations ranged from a low of .57 between Australia and Turkey to a high of .92 between Australia and the USA. In other words, the patterns of items that were scored highest versus lowest differed most between Australian and Turkish youths and differed least between Australian and American youths. For all 5 cultures from which YSR and CBCL scores have been compared for large general population samples, the YSRs yielded higher Total Problems scores. This indicates a general tendency for youths to report more problems than their parents.
Reference: Verhulst, F.C., Achenbach, T.M., van der Ende, J., Erol, N., Lambert, M.C., Leung, P.W.L., Silva, M.A., Zilber, N., & Zubrick, S.R. (2003). Comparisons of problems reported by youths from seven countries. American Journal of Psychiatry,160, 1479-1485.