A study examined whether Canadian twelfth grade students' papers would rate differently when they were written in different modes and whether there are significant differences between global (modified holistic) scores and rhetorical effectiveness (modified primary trait) scores for the same papers. Fifty students wrote on two transactional topics and two expressive topics in counterbalanced order on four occasions in English classrooms. The papers were scored by six trained raters: three using a global scoring rubric, and three others using two rhetorical effectiveness scoring rubrics, one rubric for each mode. Analysis by "t" tests revealed significant differences between scoring methods and between modes; there were no significant differences between topics within each mode. Analysis by chi square for individuals showed no differential effects of scoring method. However, writing in different modes and on different topics within mode did produce different scores for individuals scored using rhetorical effectiveness scoring. The results suggest that although holistic-type and primary trait-type scoring methods are reliable because they produce significantly different scores on the same papers of groups of students, they should not be compared without qualification; and that writing tests for purposes such as achievement, admission, placement, or competency should require students to write on more than one topic to mitigate potential injustice to individuals. (Author/HOD)