Factorial Invariance of Syndrome's Items of Achenbach's Youth Self-Report (YSR) Form

This research examined factorial invariance of Youth Self-Report (YSR) form by using confirmatory factor analysis. The form was administered on a sample of non-referred students (465 boys and 421 girls) which were selected from primary, secondary and high schools in Tehran. The sample was selected by means of multistage stratified random method. To estimate parameters and fitting an 8 correlated-syndrome model, weighted least square (WLS) function was used. The adequacy and fitting the model was assessed by RMSEA, SRMR, CFI, TLI, GFI, and AGFI indices. The findings indicated that Achenbach’s 8 correlated factor model has a good fit with data. This finding provides evidence about internal construct validity of YSR. In addition, the results showed that none of syndromes overlapped completely, indicating that syndromes were empirically distinguishable and possessed discriminant validity. The results of this study supported fitting of the Achenbach model to our data and YSR could be used to assess emotional and behavioral problems of children aged 6-18 years.