Utility of the Oswestry Disability Index for studies of back pain related disability in nurses: Evaluation of psychometric and measurement properties
Received 2 January 2009; received in revised form 25 July 2009; accepted 23 October 2009.
Abstract
Background
Disability due to back pain in nurses results in reduced productivity, work absenteeism and attrition from the nursing workforce internationally. Consistent use of outcome measures is needed in intervention studies to enable meta-analyses that determine efficacy of back pain preventive programs.
Objective
This study investigated the psychometric and measurement properties of the Oswestry Disability Index (ODI) in nursing students to determine its suitability for assessing back pain related disability in intervention studies.
Methods
Bachelor of Nursing students were recruited. Test–retest reliability and the ability of the ODI to discriminate between individuals with serious and non-serious back pain were investigated. The measurement error of the ODI was examined with the minimal detectable change at the 90% confidence level (MDC90).
Results
Student nurses (n=214) had a low mean ODI score of 8.8±7.4%. Participants with serious back pain recorded higher scores than the rest of the cohort (p<0.05). Test–retest reliability examined in 33 individuals was ICC=0.88 (95%CI 0.77–0.94). The MDC90=6%, and 36% of nursing students scored below the MDC90 indicating the tool had limited ability to detect longitudinal change in disability in this population.
Conclusion
Data from this and previous studies demonstrate that the measurement properties of the ODI are inappropriate for studying back pain related disability in nurses. The ODI is not recommended for back pain intervention studies in the nursing population and an alternative tool that is sensitive to lower levels of disability must be determined.
aCentre for Clinical Research Excellence in Spinal Pain Injury and Health, The University of Queensland, Brisbane, Australia
bDiscipline of Public Health, University of Adelaide, Adelaide, Australia
cBaker IDI Heart and Diabetes Research Institute, Melbourne, Australia
Corresponding author at: Centre for Clinical Research Excellence in Spinal Pain Injury and Health, School of Health and Rehabilitation Sciences, The University of Queensland, St. Lucia, QLD 4072, Brisbane, Australia. Tel.: +61 7 3346 7467; fax: +61 7 3365 2775.
ABSTRACT