Cognitive style research is hindered by a variety of poorly described measures and style classifications and the use of small samples. This study described and compared three group measures of impulsivity/reflectivity, internal/external locus of control; and field dependence/independence to determine the distribution characteristics, psychometric properties, and underlying factor structure of all three instruments, using responses from 274 male and female seventh grade students. Results indicated a need for psychometric refinement of measures and suggest revision of current notions of the factor structure of the domain. (Author)