Abstract
Quality of life (QoL) is affected by issues specific to illness trajectory and thus, may differ, and potentially take on different
meanings, at different stages in the cancer process. A widely used measure of QoL is the SF-36 Health Survey (SF-36; Ware
1993); therefore, support for its appropriateness in a given population is imperative. The current study aimed to examine the
conceptual (measurement) model of the SF-36, as well as closely related models, and test the measurement invariance of the
SF-36 to determine if meaningful comparisons could be made among three groups of breast cancer survivors (N = 358 [data collected in 2007–2008]; divided on time since treatment, type of treatment, and age). Good model fit was found
for one of three models based on the original design of this instrument—the items to subscales model. Two models were considered
for measurement invariance testing: (a) items to physical health/mental health and (b) items to subscales. Strong invariance
was found for time since treatment and type of treatment for both models. Weak invariance was found for age in the first model,
while strict invariance was confirmed for the subscales model. Group comparisons in QoL were made where justified. Significant
differences were found only on age for physical functioning, role limitations due to emotional problems, vitality, mental
health, and social functioning. Overall, results suggest that while the SF-36 can be used to examine differences in QoL for
various breast cancer survivors, some conceptual issues with this instrument need to be further examined.
meanings, at different stages in the cancer process. A widely used measure of QoL is the SF-36 Health Survey (SF-36; Ware
1993); therefore, support for its appropriateness in a given population is imperative. The current study aimed to examine the
conceptual (measurement) model of the SF-36, as well as closely related models, and test the measurement invariance of the
SF-36 to determine if meaningful comparisons could be made among three groups of breast cancer survivors (N = 358 [data collected in 2007–2008]; divided on time since treatment, type of treatment, and age). Good model fit was found
for one of three models based on the original design of this instrument—the items to subscales model. Two models were considered
for measurement invariance testing: (a) items to physical health/mental health and (b) items to subscales. Strong invariance
was found for time since treatment and type of treatment for both models. Weak invariance was found for age in the first model,
while strict invariance was confirmed for the subscales model. Group comparisons in QoL were made where justified. Significant
differences were found only on age for physical functioning, role limitations due to emotional problems, vitality, mental
health, and social functioning. Overall, results suggest that while the SF-36 can be used to examine differences in QoL for
various breast cancer survivors, some conceptual issues with this instrument need to be further examined.
- Content Type Journal Article
- Pages 1-19
- DOI 10.1007/s11205-011-9944-0
- Authors
- Amber D. Mosewich, School of Kinesiology, University of British Columbia, 210-6081 University Blvd, Vancouver, BC V6T 1Z1, Canada
- Valerie Hadd, Department of Sport Science, Douglas College, New Westminster Campus, 700 Royal Avenue, New Westminster, BC V3M 5Z5, UK
- Peter R. E. Crocker, School of Kinesiology, University of British Columbia, 210-6081 University Blvd, Vancouver, BC V6T 1Z1, Canada
- Bruno D. Zumbo, Department of Educational and Counselling Psychology, University of British Columbia, Scarfe Building, 2125 Main Mall, Vancouver, BC V6T 1Z4, Canada
- Journal Social Indicators Research
- Online ISSN 1573-0921
- Print ISSN 0303-8300