Wang PP, Badley EM, Gignac MAM. Activity limitation, coping
efficacy and self-perceived physical independence in people with
disability. Disabil Rehabil. 2004;26(13):785-793. [Pub
Med ID 15371050]
Objective
This study examines whether the relationships between activity limitations
and independence are mediated by coping efficacy.
[more…]
Coping efficacy reflects an individual’s appraisal of their success
in coping or managing the stressful aspects of a particular life
experience. The appraisal includes a judgment of the situation
(e.g., “I am having difficulty walking”) in relation to its
significance for people’s well-being (e.g., “I want to remain
independent”) and an evaluation of their resources and options for
coping (e.g., “I can pace myself or use a cane”).
Method
Data come from a cross-sectional survey of 286 adults, aged 55 or older,
with osteoarthritis (OA) and/or osteoporosis (OP). Physical independence
was assessed by asking to what extent respondents’ OA/OP had affected
their independence on a 5-point scale from “not at all” to “a
great deal.” Activity limitations were examined in three domains:
personal care, community mobility, and household activity. A coping efficacy
scale was derived from three items scored on a 5-point Likert-type scale
from strongly disagree to strongly agree. Structural equation modelingi was
used to test the model.
[more…]
Data from this study were derived from a community-based cross-sectional
study conducted in the Toronto and Kingston areas between 1996-1997.
As the participants were self-selected, they were older and more likely
to be female than the overall people with arthritis in Canada.
Results
Activity limitation in household activities was directly associated with
perceptions of independence, with a statistically significant standardized
path coefficient of -0.32. The effect of activity limitation in
personal care was partially mediated by coping efficacy with a
direct effect of -0.41 which was partially offset by coping efficacy
to give a net effect of -0.308. The effect of community mobility on independence
was completely mediated through coping efficacy with significant
standardized path coefficients of -0.85 (community mobility to coping efficacy)
and -0.14 (coping efficacy to independence). The overall model’s goodness
of fit was excellent (R2=0.59, chi-square/df=1.4, CFI=0.97, and
NNFI=0.97).
[more…]
See Table 3 and Figure 1 for more detailed results. A chi-square analysis
tests the fit of the model on an absolute basis and should be non-significant
to indicate a good model fit. However, given the chi-square’s sensitivity
to sample size, it often results in a statistically significant outcome.
Thus, other indices have also been developed to assess the fit of the
model. For example, the Comparative Fit Index (CFI) evaluates the fit
of the estimated model relative to the fit of the independent model (where
no relationships are estimated between variables). A model is considered
to provide a close fit when the CFI value is greater than .95.
Conclusion
Activity limitation had a detrimental effect on the level of self-perceived
independence. Coping efficacy showed a significant mediating effect
between activity limitation and self-perceived independence for the domains
of personal care and community mobility, but not household tasks. This study
suggests that how activity limitation affects perceptions of independence
varies across activity limitation domains, and indicates the importance
of incorporating activity limitation domains in future studies.
[more…]
As activities in personal care are directly related to people’s
ability to live independently, limitations in this domain are
expected to have a profound impact on people’s lives, regardless
of coping efficacy. Thus, the direct impact of activity limitations on
self-perceived independence was negative, as expected. This was partially
offset by the positive effect of coping efficacy. In contrast, activities
related to community mobility, such as using public transportation or
relying on others to drive, are often required to be carried out in a
public setting. People may feel stigmatized for their difficulties in
performing these activities. However, activity limitations in this domain
alone are unlikely to threaten people’s independent living.
List of Tables and Figures (in the publication)
- Figure 1. Revised model of coping efficacy as mediating factor
of the relations between activity limitation and self-perceived
independence.
- Table 1. Distributions of activity limitation variables of
the ACREU/Independence study population.
- Table 2. Cronbach co-efficient Alpha analyses for latent variables
included in this study.
- Table 3. Effects of three types of activity limitations on
self-perceived level of independence.
Selected Tables from the Publication (with interpretation)
Figure 1. Revised model of coping efficacy as mediating factor of the
relations between activity limitation and self-perceived independence.
Note: Numbers are path coefficients. Path coefficients assess the magnitude
of the relationships among the measured and latent variables in
the model. All path coefficients shown are statistically significant
(p‹0.05).
Table 3. Effects of three types of activity limitations on
self-perceived level of independence.
| Variables |
Direct effect |
Indirect effect through coping efficacy |
Total effect |
| Coping efficacy |
0.135ii |
0 |
0.135 |
| Personal care |
-0.406ii |
0.311 * (0.135) = 0.042 |
-0.364 |
| Community mobility |
n.s. |
FALSE |
-0.115 |
| Household tasks |
-0.321ii |
n.s. |
-0.321 |
Table 3 indicates that all three types of activity limitations significantly
affected people’s perceptions of independence. The total effects (direct
effects + indirect effects) when expressed as standardized path
coefficients were -0.308, -0.115, and -0.321, respectively. Coping
efficacy is associated with a standardized path coefficient of 0.135. However,
these effects for activity limitations were expressed in different ways.
For example, activity limitations in personal care and household activities
were directly associated with reduced perceptions of independence. However,
the effect of activity limitation in personal care was partially mediated
by coping efficacy with a net effect of -0.308. The model’s goodness
of fit indicators suggest that the final model was a very good one with
x2/df = 2.5, RMSEA = 0.02, NNI = 0.98, and AGFI = 0.96.
Supplementary Tables (with interpretation)
No supplementary information is available for this paper.
- Structural equation modeling (SEM) is a multivariate technique
that is particularly useful in nonexperimental research testing
hypothesized associations and can incorporate both unobserved
(i.e., latent or theoretical constructs) and observed variables.
In this study, latent variables were used to represent the
underlying concepts of activity limitations and coping efficacy.
The model is tested statistically using multiple regression and factor
analysis techniques.
- p‹0.05, ns stands for non-significant. A negative sign indicates
that the effect reduced the level of self-perceived independence.
