INTERNATIONAL JOURNAL OF PSYCHOLOGY, 1993.28 zyx (2). 171-184 Heart-rate Reactivity and the Type A Behaviour Pattern in Three Age Groups of Australian Children Christopher F. Sharpley, Shane D. Power, Susan J. Mollard, and Geraldine M. Parsons zyx Faculty of Education, Monash University, Melbourne, Australia The relationship between the Type A Behaviour Pattern and heart-rate reac- tivity to the onset of a typical stressor was investigated with a sample of Australian boys and girls from three age-grade levels: preschool, middle- elementary, and upper-elementary. Behaviour Pattern was measured with the Matthews Youth Test for Health (Matthews zyxw & Angulo, 1980), and data were collected on children’s second-by-second heart rate during rest and the stres- sor tasks. Reactivity to the onset of the stressor task (a puzzle game or mental arithmetic), was assessed. Results indicated that there were expected age differences in resting and stressor task heart rates, but that there was no significant difference in heart-rate reactivity between children classified as Type zyxwvu A or B Behaviour Pattern, either for the entire sample, for two extreme subsamples, or within each of the three age groups. La relation entre les comportements de type A et la reactivite du rythme cardiaque a l’introduction d’un stresseur typique a ete analysee en utilisant un echantillon australien de garsons et de filles provenant de trois niveaux sco- laires: pre-scolaire, premier et deuxieme cycles de l’elementaire. Le type de comportement a ete mesure a l’aide du test d’evaluation de la sante des jeunes de Matthews (Matthews Youth Test for Health) (Matthews et Angulo, 1980) et des donnees sur le rythme cardiaque seconde-par-seconde des enfants ont etC recueillies pendant le repos et les tlches stressantes. La reactivite a l’introduction d’une tlche stressante (un casse-t&te ou un calcul mental) a ete Cvalute. Les resultats indiquent qu’il existe des differences d’lge previsibles pour ce qui est du rythme cardiaque au repos et durant les tiches stressantes, mais qu’il n’y a pas de differences significatives dans la reactivite cardiaque entre les enfants classifies comme possedant des comportements de type A ou B, que ce soit pour l’echantillon complet, pour les deux extrCmes de l’echantil- lon, ou a I’interieur de chacun des trois groupes d’lge. Requests for reprints should be sent to Dr. C. F. Sharpley, Faculty of Education, Monash University, Clayton, Victoria, 3168 Australia. zyxwv 0 1993 International Union of Psychological Science