Development of a symptom expectation questionnaire for whiplash injury

BackgroundExpectations and beliefs appear to be important predictors of outcome following whiplash injury. Instruments for measuring these expectations in the general population have not been well studied. The objective of this study was to develop a simple symptom expectation questionnaire for whiplash injury for use in future research studies.MethodsAn existing database of 179 injury-naïve subjects who completed a 56-item checklist of expected symptoms for whiplash injury was analyzed to determine which items could correctly identify an a priori case definition of an expecter (a subject who expected at least one of these symptoms would remain chronic following whiplash injury). A total of seven of the 56 items were found to be discriminatory. The identified, discriminatory items were then tested in additional subject groups against the original questionnaire.ResultsFrom the original database of 179 subjects completing a 56-item symptom expectation checklist, 119 expected at least one of the 56 symptoms would be chronic following whiplash injury. The 119 expecters, however, all chose at least one of seven items: headache, anxious or worried, depressed, neck pain, problems sleeping, back pain, or jaw pain. Using these seven items, in two new groups of subjects given the 56-item symptom expectation checklist and then a new shortened (7-item) symptom expectation checklist one week later (and the same done for another group of 100 subjects in reverse order), all those who endorsed one of the 56 symptoms as likely to be chronic following whiplash injury (expecters) could also be identified on the 7-item checklist.ConclusionA shortened (7-item) symptom expectation checklist of commonly reported symptoms following whiplash injury (headache, anxious or worried, depressed, neck pain, problems sleeping, back pain, and jaw pain) correctly identifies subjects who expect at least one symptom will be chronic following minor head injury (i.e., an expecter). This shortened (7-item) symptom expectation checklist can be used in future population-based studies to understand the prevalence of belief patterns and expectations for whiplash injury.