Background:The Modified Overt Aggression Scale (MOAS) has been validated for use in the study of aggression in the developed world; unlike in the undeveloped world. The aim of this study therefore is to ascertain the discriminant validity of the MOAS for use in this part of the world using psychiatric in-patients at the Jos University Teaching Hospital. Methodology: Forty aggressive psychiatric patients and 40 non-aggressive healthy subjects were randomly selected for this study. The psychiatric patients were enlisted after fulfilling the ICD-10 (World Health Organization, 1993) criteria for a specific clinical diagnosis. The 40 non-aggressive subjects were mainly medical students and hospital staff. The MOAS was subsequently used to assess aggression in the entire cohort. Results: The males had higher mean global weighted score than the females in both the aggressive and nonaggressive categories. The mean global weighted scores of the aggressive and non-aggressive categories were 13.70+ 7.25 and 0.65 + 1.01 respectively. The difference in means is statistically significant; hence the MOAS has discriminant validity. Conclusion: Therefore, the modified overt aggression scale is a valid instrument in this environment for the study of aggression.

No abstract