An analysis and validation of Scale-8 on the MMPI-168 with juvenile delinquents
The purpose of this research was to provide an understanding of what Scale-8 is measuring and to determine the usefulness of this scale in a delinquent population. The sample for the analysis consisted of 312 consecutive male and female referrals to the Juvenile Court Clinic for Child Study in Detroit. Crosstabulation of item endorsement with the levels of the background variables revealed several items which showed significant differences, however the magnitude of these differences were small and did not result in overall scale differences, except for reading level. Non-readers scored significantly higher than readers. The internal reliability was.73. The factor analysis yielded ten factors accounting for 54.7% of the variance and gave some support to one of the ten factors dealing with social alienation. The samples for the validation of each of the dimensions of delinquency, emotional disturbance and assaultiveness were drawn from a pool of 821 consecutively tested delinquents based on preset criteria. The hypotheses dealt with three major issues: (1) Whether or not those rated high on a dimension would score higher on Scale-8. (2) Which scaling method (standard K-corrected T-scores or T-scores based on adolescent norms) is more accurate in discriminating on the two levels of the three dimensions. (3) To determine why nonreaders score significantly higher than readers on Scale-8. The results indicated that Scale-8 does not measure delinquency or assaultiveness in this population. However, emotionally disturbed delinquents scored significantly higher than not-emotionally disturbed delinquents. Nonreading delinquents appear to be scoring higher on Scale-8 because they are more disturbed than delinquents who can read. This research supported the use of the adolescent norms, as well as the standard K-corrected T-scores in this population, when it comes to using Scale-8 to discriminate emotionally disturbed delinquents from those who are not emotionally disturbed.
0525: Educational psychology
0632: Psychological tests