The idea that there is a
p factor, i.e., a general factor of psychopathology underlying internalizing, externalizing, and thought disorders, is gaining increasing support, creating the need for instruments to assess this factor. The purpose of this study is to determine whether the total score of the Achenbach and Rescorla’s (
2001) Youth Self-Report (YSR), an instrument that measures eight syndromes of internalizing, externalizing, and thought disorders, provides a reliable measure of the
p factor in adolescents. For this purpose, we tested a bifactor model using exploratory structural equation modeling on a large cross-cultural sample of Algerian, French and Tunisian adolescents (N = 3,705). The results established that the YSR total score is a reliable measure of a general factor of psychopathology that explains two thirds of the common variance. Most syndrome scales are reliable measures of the whole formed by the general factor and the syndrome they are designed to measure, but only the Rule-Breaking Behavior syndrome scale explains a significant proportion of the variance above and beyond what is attributable to the general factor. Multigroup analyses showed that the total score and the Rule-Breaking Behavior scale score are reasonably invariant across genders, age groups, and countries, allowing for the examination of differences between subgroup latent means. The YSR total score thus appears to provide a reliable measure of the general factor of psychopathology that is robust across genders, ages, and countries.