ABSTRACT
Formulas for premorbid intelligence estimates are typically derived by linear regression and are therefore biased in individual cases because of regression to the mean. It is shown that it is inappropriate to compare such IQ estimates with current IQ scores to determine whether a decline from premorbid levels has occurred. This widespread practice grossly overestimates the probability of an IQ decline in the below-average range and grossly underestimates it in the above-average range, with serious implications for clinical practice. The authors present a formula for computing unbiased estimates of IQ decline as well as a test of the null hypothesis of no decline. Corresponding tables for several combinations of test indices and estimation methods are included for practical reference.
Subject(s)
Brain Injuries/psychology , Disability Evaluation , Intelligence Tests/standards , Intelligence , Adult , Bias , Brain Injuries/epidemiology , Data Interpretation, Statistical , Humans , Male , Practice Guidelines as Topic , Regression Analysis , Reproducibility of Results , Wechsler Scales/standardsABSTRACT
This reply responds to W. M. Grove's (2001) critique of H. O. F. Veiel and R. F. Koopman's (2001) article on bias in widely used methods of estimating premorbid IQ. In this reply, the authors show that Grove is misrepresenting part of Veiel and Koopman's arguments, extend them to show that the proposed adjustment to regression estimates of IQ not only is unbiased but also is the maximum-likelihood estimate of the true IQ, and argue that Grove's notion of the acceptability of biased methods in judicial proceedings reflects a fundamental misapprehension of their nature and purpose.
Subject(s)
Intelligence Tests/standards , Intelligence , Bias , Data Interpretation, Statistical , Expert Testimony , HumansABSTRACT
This study examined the self-efficacy status of depressed versus nondepressed adolescents. As predicted, self-efficacy was negatively correlated with depression. A three-way interaction of Sex x Age x Level of Depression suggested separate analyses for males and females. Regression analysis revealed age-related changes in the dependence of depression scores on general, academic, physical and social self-efficacy status. It was concluded that self-efficacy has an important relationship with adolescent depression. The implications of these findings are discussed.
Subject(s)
Depression/psychology , Psychology, Adolescent , Self Concept , Adolescent , Age Factors , Analysis of Variance , Female , Humans , Male , Personality Inventory , Regression AnalysisABSTRACT
In response to the need expressed in the literature on adolescent depression, recent studies have examined the incidence of affective disorders. However, there continues to be a paucity of research on the prevalence of depressive symptomatology in nonpatient adolescents. The Canadian literature is especially lacking in this area. The present study examined the prevalence of depression in a sample of 366 Canadian high school students. Consistent with similar research in the United Kingdom and the United States, 31.4% of the sample were midly to clinically depressed as measured by the Beck Depression Inventory. Significant sex differences were found; these are discussed in the context of age and level of depression. The need for further research on adolescent depression is emphasized.
Subject(s)
Depressive Disorder/epidemiology , Students/psychology , Adolescent , Age Factors , British Columbia/epidemiology , Depressive Disorder/diagnosis , Female , Humans , Male , Prevalence , Sex Factors , Surveys and QuestionnairesABSTRACT
The evidence indicates that adolescent depression may be more difficult to recognize than its adult counterpart, although the reasons for this difficulty remain unclear. The research in this area is in part impeded by the lack of adolescent-specific measures of personality functioning. In this study the personality styles, expressed concerns, and behavioral tendencies of depressed adolescents were investigated by means of the Millon Adolescent Personality Inventory (MAPI), a relatively new personality inventory designed specifically for this age group. Three hundred sixty-six high school students completed the Beck Depression Inventory (BDI) and the MAPI, resulting in 332 valid and reliable MAPI profiles. The data were reduced to two factors, accounting for 65.1% of the total variance, by means of a principal components analysis. The two factors were interpreted as two dimensions of personality functioning associated with depression in adolescents. The first dimension suggested a socially withdrawn, overtly recognizable depression, whereas the second presents acting-out tendencies that may overshadow depressive symptomatology. The findings are integrated with the theoretical positions represented in the literature. Theoretical and practical implications for the use of the MAPI with depressed adolescents are discussed.
