Julia D. Grant1, 2, Boo Johansson2, 3, & Gerald E. McClearn2, 4.
Much research, stemming primarily from Rotter's work (J.B. Rotter, 1966, Psychological Monographs, 80, 1-28), has indicated that beliefs about personal control can influence behavior. One topic that has received substantial attention in recent years is perceived control over health. Although numerous researchers have used the Multidimensional Health Locus of Control scale (MHLC; K.A. Wallston, B.S. Wallston, and R. DeVellis, 1978, Health Education Monographs, 6, 160-170) to examine health-control beliefs and their associations with other health and personality measures, little work has been done investigating health locus of control in individuals over the age of 80 years. Furthermore, the influence of genetic and environmental factors on health-control beliefs has not been systematically examined in previous studies. The Swedish OCTO-Twin study provides the opportunity to investigate genetic and environmental influences on attributions of control over health. In the present analyses, we examined health-control beliefs in a sample of 94 octogenarian twin pairs (MZ=44, like-sex DZ=50; mean age=82.6 years). Factor analysis, with a three-factor solution specified, produced the same factors originally proposed by Wallston and colleagues. All three subscales had acceptable internal consistency (alphas from .72 to .76). Associations between health-control beliefs and other health measures (e.g., self-rated health, hospital visits, exercise) were modest. Intraclass correlations indicated that genetic influences were present for the Chance and Powerful Others subscales, but not for the Internal subscale. Quantitative genetic analyses confirmed significant genetic influences on the Chance subscale (h2=.64) as well as significant familiality on the Powerful Others subscale (h2=.29).
Address: Department of Psychiatry, Washington University School of Medicine, 40 N., Kingshighway, Suite 1, St. Louis, MO 63108, Phone: (314) 286-2299, Fax: (314) 286-2213, Email: julie@matlock.wustl.edu
1Department of Psychiatry, Washington University School of Medicine, 40 N. Kingshighway, Suite 1, St. Louis, MO 63108 2Center for Developmental and Health Genetics, 101 Amy Gardner House, PSU, University Park, PA 16802 3Institute for Gerontology, Halsohogskolan, Box 1038, S-551 11 Jonkoping, Sweden 4Department of Biobehavioral Health, 315 East HHD, PSU, University Park, PA 16802 5OCTO-Twin is supported by Grant AG08861