EVALUATION OF THE ORIGINAL ONTARIO-CHILD-HEALTH-STUDY SCALES

This article presents evaluative information on the use of the origina l Ontario Child Health Study scales to serve as ordinal-level measures of conduct disorder, hyperactivity and emotional disorder among child ren in the general (non clinic) population. Problem checklist assessme nts were obtained from parents and teachers of children aged six to 16 and youth aged 12 to 16 drawn from a general population (n = 1,751); and a mental health clinic sample (n = 1,027) in the same industrializ ed, urban setting. The results showed that the original OCHS scales po ssess adequate psychometric properties to be used as ordinal-level mea sures of disorder. Correlations between individual items and their hyp othesized scales were very strong, indicating convergent validity, whi le correlations between the same items and other (non hypothesized) sc ales were lower, indicating discriminant validity. Item analyses indic ated that individual scale items possess both convergent and discrimin ant validity. Although the scales were skewed to the positive end of t he continuum, they demonstrated good internal consistency (all estimat es greater-than-or-equal-to 0.74) and test-retest (all estimates great er-than-or-equal-to 0.65) reliability. Finally, three different validi ty analyses confirmed hypotheses about how the original OCHS scales sh ould perform if they provide useful measures of disorder