Аннотация:Abstract This study investigated the influence of childrens' and teachers' sex on Type A assessment using the Matthews Youth Test for Health (MYTH). Two hundred and ten teachers and student teachers read vignettes describing the behavior of children reacting to challenges in a school environment. Teachers were randomly assigned to one of four vignettes: (1) male Type A child; (2) female Type A child; (3) male Type B child; (4) female Type B child. Higher MYTH scores were assigned to Type A compared with Type B children. However, among Type A children, male teachers assigned significantly lower MYTH scores to girls than to boys; the MYTH ratings made by female teachers for Type A children were equivalent for boys and girls. These results suggest that the sex of the child and the teacher interact significantly to influence aspects of Type A assessment, but that classification overall reflects observed behavior.