A concurrent validity study of the MBTI, MMTIC -R and SSQ with middle school students

The difficulty in finding a suitable testing instrument to assist in the determination of personality type in children is the inspiration for the current study. The search for such a valid instrument becomes even more difficult when the instrument is expected to measure personality types or temperaments in the face of a developing child. The purpose of this study was to examine the MMTIC-R and the SSQ and determine if they, in fact, measure the same constructs as measured by the MBTI.

The MBTI, MMTIC-R and SSQ measure sixteen combinations of four personality types. These types are labeled as Extraversion or Introversion, Sensing or Intuition, Thinking or Feeling and Judging or Perceiving for the MBTI and MMTIC-R. They are labeled as Extroversion or Introversion, Practical or Imaginative, Thinking or Feeling and Organized or Flexible for the SSQ.

The sample included seventh and eighth-grade students from two middle schools in Northeast Tarrant County. Two hundred and nineteen students participated in the study. The students were considered in two groups. A selected group of gifted/talented students were compared with the control group of students. Statistics utilized to test the hypotheses included Cochran's Q Test, Correlations, Phi Coefficients, Analysis of Variance and Self-Selection Ratio. Differences were considered based on reading level, which was determined by whether or not a student passed the seventh-grade TAAS reading portion, gender and the gifted/talented group versus the control group.

Findings included significant differences in reported preferences across the three instruments. Significant correlations were noted between the three instruments, however, these correlations were not strong for all scales. Some differences were noted in gender, with females reporting more Feeling preferences and males reporting more Thinking preferences. Differences were noted between the two groups identified with the gifted/talented group reporting more Intuitive preferences than the control group. No differences were in preferences based on reading level.

The study suggests that the construct of personality type varies between the MBTI, SSQ, and the MMTIC-R. Implications for this variability across instruments are discussed.