Description/Samples/Epidemiologic Evidence
SELF-EFFICACY
Definition: "An individual's sense of competence or ability in general or in particular domains." Bandura (1977) differentiates self-efficacy & personal control as follows: whereas personal control beliefs focus on question of whether one can control an outcome, self-efficacy beliefs focus on the evaluation of one's ability to effectively perform behaviors necessary to realize that outcome.
Measures
(1) Rodin & McAvay self-efficacy measure (Rodin & McAvay, 1992) Designed for older adults. 8-9 items, 4-point agree/disagree format. Interpersonal efficacy (dealing with friends & family) & instrumental efficacy (finances, safety, productivity).
o Albert et al. (1995). Of 22 demographic, physical, and psychosocial variables considered, self-efficacy was one of only four variables (the others were education, strenuous activity, peak pulmonary expiratory flow rate) that were predictive of cognitive change over a 2.5 year period in 70 to 79-year-old men and women.
o Seeman et al. (1993). Instrumental efficacy beliefs were related to better peformance on tests of memory & abstraction in men, but not in women. Interpersonal efficacy beliefs were not associated with cognitive ability in either men or women. (Relationship between specific efficacy beliefs about intellectual or memory abilities & performance on memory or more general intelligence tests has been thoroughly examined. Positive, cross-sectional relationships have been found between targeted efficacy beliefs & better memory or intellectual performance. Studies looking at more generalized control beliefs have found them to be less strongly related to intellectual performance (Lachman et al., 1982; Lachman 1983, 1986).)
o Seeman et al. (1996). Stronger baseline instrumental efficacy beliefs predicted better verbal memory performance among follow-up among men but not among women, controlling for baseline verbal memory score.
o Seeman (1999). Weaker instrumental self-efficacy beliefs predicted declines in reported functional status (Nagi). Instrumental efficacy beliefs were also negatively related to reports of onset of Katz ADL among men. Self-efficacy beliefs were unrelated to changes in actual physical performance abilities for both men & women, however. (In other studies, self-efficacy beliefs have been shown to influence levels of activity among various patient populations).
(2) General Self-Efficacy Scale (Sherer et al., 1982)
o Penninx et al. (1997). Longitudinal Aging Study Amsterdam. Self-efficacy (as measured by the General Self-Efficacy Scale) was not related to mortality.
(3) ISR Personal Efficacy Index (Institute for Social Research, University of Michigan)
o Lachman (1985; 1986). Panel Study of Income Dynamics (PSID); multiple age cohorts aged 35-69. Personal Efficacy Index = 3-item scale that assesses extent to which one is successful at accomplishing goals. Items ask whether respondent usually thinks his life is working out the way he wants it to, whether the respondent usually carries out plans the way he has expected to, & whether the respondent usually finishes things once he has started them.
o Maciejewski PK et al. (2000). Americans' Changing Lives (ACL) Study. 2858 adults aged 25+ followed for 3 yrs. Self-efficacy Index = 6-item index, a combination of Pearlin's Personal Mastery Scale & Rosenberg's Self-Esteem Scale. Among persons with prior depression, life events had a negative impact on self-efficacy. Among persons without prior depression, life events had no effect on self-efficacy.
Epidemiologic findings
Self-efficacy is related to health behaviors (smoking cessation, pain mgmt, weight control, adherence to health prevention programs).
o Winkleby MA et al. (1994). 411 participants in 6-yr multiple CV risk factor intervention study. Low self-efficacy was associated with low probability of making positive changes.
PERSONAL CONTROL
Personal control beliefs, a.k.a. locus of control (LOC) or personal mastery beliefs, reflect individuals' beliefs regarding the extent to which they are able to control or influence outcomes. Existing literature on control beliefs in relation to health largely reflects the "internal vs. external" conceptualization, with assessment of individuals in terms of the extent to which they see control as residing primarily in themselves vs. elsewhere (i.e., in others or chance).
Generalized measures:
(1) Personal Mastery Scale (Pearlin & Schooler, 1978; Pearlin et al., 1981).
Mastery is the "extent to which one regards one's life-chances as being under one's own control in contrast to being fatalistically ruled." 7 items, answered on a 4-point (strongly agree/disagree) scale. Scores range from 7 (low mastery) to 28 (high mastery). This scale is perhaps the most widely used control measure in health research.
o Lachman & Weaver (1998a, 1998b). MacArthur Midlife Survey. 3 national probability samples of men & women aged 25-75 years; sample 1: n=1014; sample 2: n=1195; sample 3: n=3485. Used Personal Mastery Scale, plus 5 new items. Sense of control has 2 dimensions: (a) personal mastery = one's sense of efficacy or effectiveness in carrying out goals, and (b) perceived constraints = to what extent one believes there are obstacles or factors beyond one's control that interfere with reaching goals. Persons with lower income had lower perceived mastery & higher perceived constraints, as well as poorer health. For all income groups, higher perceived mastery & lower perceived constraints were related to better health, greater life satisfaction, & lower depressive symptoms. Participants in the lowest income group with the highest sense of control showed levels of health & well-being comparable with higher income groups.
o Kubzansky et al. (2000). MacArthur Studies of Successful Aging. 1189 high-functioning men & women aged 70-79. In cross-sectional analyses, sense of control (Personal Mastery Scale) was not associated with race, nor did it mediate effect of race on psychological distress.
o Penninx et al. (1997). Longitudinal Aging Study Amsterdam. 3805 men & women aged 55-85 yrs, followed for 2.5 yrs. Greater feelings of mastery (5-item version of Personal Mastery Scale) were associated with lower mortality.
o Dew MA et al. (1997). 170 HIV+/HIV- men followed for 1 yr. Low sense of personal mastery was risk factor for major depressive disorder.
o Guralnick, Fried et al. (1995). Women's Health and Aging Study. Used 2 items from the Personal Mastery Scale ("I can do just about anything I really set my mind to", "I often feel hopeless in dealing with the problems of life").
o Penninx et al. (1998). Women's Health and Aging Study. "Emotional vitality" was defined as having a high sense of personal mastery (2 items from Personal Mastery Scale), being happy, and having low depressive symptoms (GDS) & anxiety (SCL, 4 items).
(2) Internal-External Locus of Control Scale (Rotter I/E Scale; Rotter, 1966)
23 I/E items, forced-choice format, plus 6 filler questions. Scoring: 1 point is given for each external statement selected. Scores range from 0 (most internal) to 23 (most external). Completion time 15 min. No upper or lower age limit. Widely used in psychology (most frequently with college students), but less so in epidemiology.
o Bosma et al. (1999). Pop'n based study in Eindhoven, The Netherlands. 2462 men & women aged 25-74 followed for 6 yrs. Low perceived control (11-item Dutch version of Rotter I/E Scale) was more common among low socioeconomic groups & was associated with mortality. Adjustment for perceived control substantially lessened the association between socioeconomic status & perceived control. Low socioeconomic status is related to mortality partly because people with low socioeconomic status more often perceive low control.
(3) Internality, Powerful Others and Chance Scales (Levenson, 1981)
Multidimensional measure based on Rotter I/E scale. Whereas a unidimensional conception (i.e., internality & externality are opposite poles of a continuum) of control implies that internal & external orientations are mutually exclusive, Levenson's view is that they may be independent because individuals may believe they are in control of outcomes yet at the same time acknowledge the operation of chance & other external forces in their lives. Indeed, correlations between the internal & external dimensions are consistently low and nonsignificant (Lachman 1986, p. 210).
o Lachman (1986) summarizes a number of studies of the relationship between control (measured with Levenson Scales) & cognitive function in aging populations.
(4) Adult Nowicki-Strickland Internal-External Control Scale (ANSIE; Nowicki & Duke, 1974).
40 items. Designed for non-college adults. Language & format (True/False) are less difficult than Rotter I/E Scale. An upgrade of authors' scale for children.
o Medline search of "Nowicki" (kw) turned up no references for adult populations, 1987-present.
Domain-specific measures:
(5) Personality in Intellectual Aging Contexts (PIC) control scales (Lachman, Baltes, Nesselroade, & Willis, 1982)
Assesses beliefs & attributions about intellectual functioning associated with everyday situations & lab tasks. Developed for use with the elderly. Modeled after Levenson. 3 scales, 12 items each: (a) Internal control: Responsibility for modifications or maintenance of intellectual functioning lies within one's own control. (b) Chance control: Belief that there is nothing that can be purposefully done to preserve or modify intelligence; change in abilities is due to external forces. (c) Powerful Others Control: Dependence and reliance on other people for accomplishing intellectual tasks, due to the belief that others are better able to carry out such tasks.
o Lachman (1986) summarizes a number of studies of the relationship between control (measured with PIC scales) & cognitive function in aging populations.
(6) Multidimensional Health Locus of Control Scale (MHLC; Wallston et al., 1978) 18 items. 3 subscales, 6 items each: (a) personal control or internality, (b) effectiveness of powerful others, (c) role of chance in determining one's health status. Well-known & often used to study causal beliefs relevant to health. Helped spawn literature concerned with activity vs. passivity in responses to medical procedures.
o Medline search of "Multdimensional Health Locus of Control Scale" (kw) turned up no references, 1987-present.
(7) Mental Health Locus of Control Scale (Hill & Bale, 1980)
May be of interest to researchers studying mental illness. There has been minimal psychometric clarification & refinement of these scales. Authors themselves have not added much to a literature that may yet evolve from this measure. A bipolar measure of beliefs about control of therapeutic changes. Internal pole reflects beliefs that the patient bears responsibility for changes; external pole places the burden on therapist. Self-administered 22-item scale.
Epidemiologic/other findings:
o Evidence linking sense of control to health is mixed, with evidence for both more positive & more negative health outcomes associated w/stronger sense of control. It is important to note that much of the evidence comes from experimental studies, where sense of control is not directly measured but rather inferred from environmental manipulations.
o Sense of control has been linked to better psychological health (Rodin 1986; Rodin, Timko & Harris, 1985; Haidt & Rodin, 1995), lower CHD incidence (Karasek et al., 1982; Marmot et al., 1997 - job control), better self-rated health & functional status (M Seeman & Lewis, 1995), maintenance of cognitive function (T Seeman et al., 1993), & lower mortality (M Seeman & Lewis, 1995; Rodin & Langer, 1977).
o Stronger sense of control is associated with worse health outcomes under certain circumstances. Having strong internal control beliefs in situations that do not allow for such personal causation tend to be detrimental in terms of physiologic activation. A chronic "person-environment mismatch" may result in increased pathophysiology (Rodin 1986; Seeman 1991; Thompson et al., 1988).
POWERLESSNESS
Powerlessness Scale (Kohn & Schooler, 1983)
Powerlessness is defined as "the expectancy or probability held by the individual that his own behavior cannot determine occurrence of the outcomes . he seeks." Scale is simple, meant for survey administration. 4 items, Agree/disagree response.
SENSE OF COHERENCE
Sense of Coherence Scale (Antonovsky, 1979, 1987)
Sense of cohrerence is defined as "a global orientation that expresses the extent to which one has a pervasive, enduring though dynamic feeling of confidence that one's internal and external environments are predictable and that there is a high probability that things will work out as well as can be reasonably expected" (Antonovsky, 1979, p.123). It differs from personal control in that "the crucial issue is not whether power to determine such outcomes lies in our own hands or elsewhere. What is important is that the location of power is where it is legitimately supposed to be" (p. 128). 29 items, 7-point response choice. Items refer to a wide variety of stimuli & situations.
o Poppius E et al. (1999). Helsinki Heart Study. 4405 middle-aged working men followed for 8 yrs. Among white-collar workers, low sense of coherence (what measure?) was associated with incident CHD. A similar effect was not observed among blue-collar workers.
o Kivimaki M et al. (2000). 577 municipal employees followed 4-5 yrs. SOC predicted sickness absence in women but not men in 4 yr follow-up. SOC did not predict psychological or somatic health complaints in 5-yr follow-up.
o Davey Smith & Egger (1997). Changes in population distribution of SOC do not explain changes in overall mortality [letter].
