PhD, Ohio State University at
Citation Corrigan, J. (2000).
Satisfaction With Life Scale. The Center for Outcome Measurement
in Brain Injury. http://www.tbims.org/
combi/swls ( accessed
This citation is for the COMBI web material. Dr. Corrigan
is not the scale author for the SWLS.
SWLS was developed using classical test construction approaches
to both select an initial item pool and subsequently narrow the
instrument to five items that inquire about respondents' overall
assessment of their lives. Generally the cognitive appraisal involved
in measuring life satisfaction is believed to require a comparison
by individuals between the current status of their lives and self-defined
expectations regarding what they would like their lives to be. This
comparison may be in relation to a self-defined ideal, to other
people, or to one's own past. The SWLS does not measure satisfaction
with specific domains of life (e.g., family, employment, and income).
Combining domain-specific ratings to attain a global indication
of life satisfaction has been criticized for assuming that individuals
place equal value on all life areas. Summing or other weightings
imposed by the instrument lose the subjective valence of the domains.
The initial item selection for the SWLS included 48 items that all
had face validity as indicators of one's appraisal of life. Initial
factor analysis revealed a three-factor structure, with 10 items
loading highly (greater than .60) on a factor reflecting cognitive-judgmental
evaluative processes. Five of these items were considered redundant
in wording or word choice, thus leading to the current five items
of the SWLS.
Initial and subsequent studies have examined the internal consistency
of the SWLS and alpha coefficients have repeatedly exceeded .80
(see Pavot & Diener, 1993). For instance, Diener and colleagues'
original study found an alpha coefficient equaling .87 for 176 undergraduates
at the University of Illinois.
test-retest reliabilities have been generally acceptable (see Pavot
& Diener, 1993), though lower than desirable scores result when
the time span between test and re-test is longer and situational
influences affect responses. In the original validation study Diener
and colleagues found two-month test-retest correlation coefficients
equal to .82 for 76 students re-tested from their original sample.
Alfonso and Allison (c.f., Pavot & Diener, 1993) reported a
test-retest correlation coefficient of .89 for subjects retested
after 2 weeks.
the initial validation study Diener and colleagues factor analyzed
the five-item scale and, based on a scree test of eigen values,
concluded that it represented a single factor. That factor accounted
for 66% of the variance in the instrument. Again, subsequent studies
have replicated these factor analytic findings. Item to total score
correlations have ranged from .57 to .66. When comparing individual
item factor loadings, as well as item to total score correlations,
the first item is consistently the most associated, while the fifth
item is frequently the least well associated. However, factor loadings
in the subsequent analyses all exceeded the minimum criterion of
.60 used by Diener and colleagues in the original development.
Heinemann and colleagues at the Rehabilitation Institute of Chicago
(personal communication) computed a Rasch analysis on 777 respondents
to the TBI State Demonstration Grant needs assessment conducted
in Illinois. As with previous factor analyses, Item #5 had the poorest
fit and the validity of its inclusion may need to be examined for
persons with TBI.
The original validation studies correlated the SWLS with ten other
measures of subjective well being. Most measures correlated at an
r = .50 or higher for each of the two samples from the original
work. Subsequent studies have found comparable or higher correlations
with other populations when interviewer ratings, informant reports,
or other objective measures (e.g. the Andrews/Withey scale, Fordyce
global scale) are used.
Evidence for the construct validity of the SWLS can be drawn from
a number of investigations. For instance, test-retest stability
has been found to decline as time between testing increases, suggesting
that the instrument is sensitive to changes that occur with life
and not just a direct effect of stable personality traits. Additionally,
the SWLS has shown consistent differences between populations that
would be expected to have different qualities of life (e.g., psychiatric
patients, or male prison inmates). The SWLS has also been found
to change in the expected directions in response to major life events,
such as elderly caregivers who had a spouse diagnosed with primary
degenerative dementia (Vitaliano et al, 1991), and patients receiving
psychotherapy (Friedman reported in Pavot & Diener, 1993).
SWLS has been administered in conjunction with measures of positive
and negative affective appraisal. The SWLS tends to correlate with
scales measuring both constructs even though the two are unrelated.
The absolute values of these correlations range from .26 to .47,
indicating that the SWLS taps a dimension of subjective well being
different from either positive or negative affectivity. Also consistent
with theoretical postulations about subjective well being, SWLS
scores have been found to be positively correlated with extroversion
and inversely correlated with neuroticism (Diener et al, 1985; Pavot
& Diener, 1993, Pavot, Diener, Colvin & Sandvik, 1991).
Corrigan, Smith-Knapp & Granger (1998) reported a mean of 19.0
and standard deviation of 7.6 for a cross-sectional sample of 98
patients with TBI six months to 5 years post-discharge from acute
rehabilitation. Time post-injury was significantly associated with
higher SWLS total score.
et al (1999) reported a mean and standard deviation of 19.58 (8.29)
1 year post-injury and 20.98 (9.39) 2 years post-injury for 179
patients admitted to a specialized brain injury rehabilitation unit.
Higher life satisfaction was associated with employment, less depression,
the absence of a prior history of substance abuse, greater social
integration, and lower Glasgow Coma Scale score at emergency department
admission. Changes in SWLS scores from Year 1 to Year 2 were associated
with depression and marital status.
et al (1999) reported a mean of 16.2 for a sample of 875 persons
with TBI living in the community a median of 7 years post-injury.
The sample was identified from the state vocational rehabilitation
roles, mailing lists of the Brain Injury Association of Illinois,
and brain injury rehabilitation providers in the state. A linear
transformation of the Total score using Rasch analysis revealed
associations between higher life satisfaction and lower levels of
unmet needs, having a spouse or partner, the perception that the
TBI had a minimal impact on one's life, having more than a high
school education, the perception that one's friendships, living
situation and employment had not changed for the worse, better emotional
status since TBI onset, and greater time post-injury.
TBI Model Systems database as of April, 2000 included a limited
number of cases with SWLS total scores. Descriptive statistics are
provided in the following table. (The SWLS was added to the TBI
Model Systems database April 4, 1998.)
Pavot and Diener (1993) for data on a variety of subpopulations,
including students with disabilities.
Consortium for Spinal Cord Medicine (1999) for data on persons with
traumatic spinal cord injury.