title: Health locus of control in late life: a study of genetic and environmental influences in twins aged 80 years and older.
abstract: The factor structure of health locus of control (Form A; K. A. Wallston, B. S. Wallston, & R. DeVellis, 1978) was examined in 420 octogenarians (M age = 83.2 years), and the contributions of genetic and environmental factors to health-control beliefs in 141 octogenarian twin pairs (71 identical, 70 same-sex fraternal) were estimated. Factor analyses reproduced previously proposed factors (Internal, Chance, and Powerful Others). Associations between health-control beliefs and life satisfaction, depression, and other health-related measures (e.g., self-rated health, outpatient contacts, and hospitalization), were modest. Quantitative genetic analyses revealed significant shared environmental influence on the Chance subscale, and significant familiality (attributable to a combination of genetic and shared environmental influences) on the Powerful Others subscale; there was no evidence of familiality on the Internal subscale.
authors.affiliation: Institute of Gerontology, University College of Health Sciences, Jönköping, Sweden.
authors.forename: B
authors.initials: B
authors.lastname: Johansson
authors.forename: J D
authors.initials: JD
authors.lastname: Grant
authors.forename: R
authors.initials: R
authors.lastname: Plomin
authors.forename: N L
authors.initials: NL
authors.lastname: Pedersen
authors.forename: F
authors.initials: F
authors.lastname: Ahern
authors.forename: S
authors.initials: S
authors.lastname: Berg
authors.forename: G E
authors.initials: GE
authors.lastname: McClearn
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000235:genetics* / Q000523:psychology*; D001294:Attitude to Health; D004777:Environment; D005260:Female; D006304:Health Status; D006801:Humans; D007389:Internal-External Control; D008297:Male; D017060:Patient Satisfaction; D011788:Quality of Life