Transcript A Reliability Generalization of the Life Satisfaction Index

A Reliability
Generalization of the
Life Satisfaction Index
K. A. Wallace & J. C. Caruso
University of Montana
Presented at the Annual Meeting of
The Gerontological Society of America, November 2002.
Purpose

To examine score reliability for a widely
used measure of life satisfaction, the Life
Satisfaction Index (LSI; Neugarten et al., 1961)

Average score reliability
 Variation in score reliability as a function
of sample characteristics (e.g., gender;
mean age; scale length; etc.)
Developing Ratings of Life Satisfaction


Crafted to assess well-being using a subjective
evaluation of one’s own present and/or past life
Part of the Kansas City Study of Adult Life
(Neugarten et al., 1961)
 Thematic
analysis of measures of adjustment and
morale
 5 components of well-being:





Zest versus apathy
Resolution and fortitude
Congruence between desired and achieved goals
Self-concept
Positive mood tone
The Scales
Life Satisfaction Index A (LSIA)
 Life Satisfaction Index B (LSIB)
 Life Satisfaction Index Z (LSIZ; Wood et al., 1969)
 18-item version (Adams, 1969)
 8-item version (LSIW; James et al., 1986)
 30-item version (Maynard, 1993)

Reliability Generalization
Meta-analytic technique
 Examines average score reliability (e.g.,

Vacha-Haase, 1998)

Examines relationships between study
characteristics and score reliability
 Sample size
 Scale length
 Mean age of sample
 Standard deviation of age
 Gender
 Mean LSI
 Standard deviation LSI
 Language of administration
 Type of sample
Method – Data Collection

PsycINFO literature search
 Life

satisfaction index and LSI
157 possible articles
 59.87%
no mention of reliability
 9.56% indicated LSI reliable test, no data
 6.37% cited reliability from previous work
 3.18% reported reliability in unusable form
 .64% not empirical
 1.27% could not be obtained
 19.11% (30) provided usable reliability information

Total of 34 samples used
Descriptive Statistics for Sample
Characteristics (N=34)
Variable
M
Sample size
235.53
Scale length
17.09
Mean age
61.79
Std dev age
6.89
Proportion female
.63
Mean LSI
15.56
Std dev LSI
3.40
Lang of admin
.78
Sample type
.26
SD
328.46
4.21
17.17
3.38
.28
13.01
2.34
.42
.51
Range
20-1571
8-30
20.2-83.3
3-15.7
0-1.00
3.08-65.5
.52-11.83
0-1.00
0-1.00
Results

Average Score Reliability
 Mean
= .79 (SD = .10)
 Median = .79
 Range of .56 (.42 to .98)

Bivariate correlations
 Score
reliability was not significantly related to: scale
length, mean age, standard deviation of age,
proportion female, sample size, mean LSI, or
standard deviation LSI

t tests
 No
difference in score reliability as function of
language of administration or sample type
Discussion

Adequate average score reliability for the
LSI
 File

drawer problem?
No relationship between score reliability
and sample characteristics
 Preliminary
evidence for adequate reliability of
scores generated with LSI across various
sample characteristics

Limitations?
Future Research & Implications
Replication
 Conceptualization of reliability as property
of scores (e.g., Wilkinson & APA Task Force on Statistical

Inference, 1999)

Inclusion of more detailed demographic
and reliability information