Abstract
The relationship between normal variation in IQ and common psychopathology was examined in a sample of 339 5- to 16-year-olds who were seen at a tertiary psychiatric clinic. The mean IQ was 9.6 points lower (95% CI 5.5 to 13.6 points lower) for conduct than for emotional disorders, with mixed disorders in between. For these common disorders, the mean IQ was 6.0 points lower (95% CI 1.6 to 10.3 points lower) for females than males. IQ variation in the normal range was inversely related to a dimensional measure of conduct problems — an association that was not attributable to social class or mediated by scholastic attainments. Other dimensional measures of psychopathology — covering emotional symptoms, developmental immaturity and relationship difficulties — were not significantly correlated with IQ. Limitations of the study are discussed in the paper.
Résumé
La relation entre la variation normale du QI et la psychopathologie commune a été examinée chez un échantillon de 339 jeunes âgés de 5 à 16 ans vus à une consultation psychiatrique tertiaire. Le QI moyen était de 9.6 points plus bas (95% CI 5.5 à 13.6 points plus bas) pour les troubles des conduites que pour les troubles affectifs, avec les troubles mixtes entre les deux. Pour ces troubles communs, le QI moyen était 6.0 points plus bas (95% CI 1.6 à 10.3 points plus bas) chez les filles que chez les gar¢ons. La variation du QI dans les limites de la normale était inversement proportionnelle à une mesure dimensionnelle des troubles des conduites-une association qui n'était pas attribuable à la classe sociale ou liée aux acquisitions scolaires. D'autres mesures dimensionnelles de la psychopathologie des symptômes affectifs, l'immaturité du développement et difficultés relationnelles -n'étaient pas corrélées significativement avec le QI. Les limites de l'étude sont discutées dans cet article.
Zusammenfassung
Die Beziehung zwischen der normalen Variabilität des IQ und häufiger Psychopathologie wurde an einer Stichprobe von 339 5- bis 16-Jährigen untersucht, die sich an einer spezialisierten psychiatrischen Einrichtung vorstellten. Der Durchschnitts-IQ war um 9,6 Punkte niedriger für Störungen des Sozialverhaltens als für emotionale Störungen (95%iges CI 5,5 bis 13,6 Punkten niedriger).
Die gemischten Störungen lagen dazwischen. Für diese häufigen Störungen lag der Durchschnitts-IQ um 6,0 Punkte niedriger bei den Mädchen als bei den Knaben (95% iges CI bei 1,6 bis 10,3 Punkte niedriger). Die IQ-Variabilität im Normbereich war umgekehrt proportional zur dimensionalen Messung der sozialen Verhaltensauflälligkeiten -eine Assoziation, die nicht der sozialen Schichtgehörigkeit zugeschrieben werden konnte und auch nicht abhängig von schulischen Erfolgen war. Andere dimensionale Messungen der Psychopathologie, die emotionale Symptome, Reifungsverzögerungen und Beziehungsschwierigkeiten umfaßten, korrelierten nicht signifikant mit dem IQ. Die Einschränkungen der Studie werden in dem Artikel diskutiert.
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Goodman, R. The relationship between normal variation in IQ and common childhood psychopathology: A clinical study. European Child & Adolescent Psychiatry 4, 187–196 (1995). https://doi.org/10.1007/BF01980457
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DOI: https://doi.org/10.1007/BF01980457