Comparison of self-reported and recorded vaccinations and health effects in Australian Gulf War veterans

BackgroundVaccinations, and multiple vaccinations in particular, have been associated with adverse health effects in veterans of the 1990/1991 Gulf War. However, exposure assessment has usually been based on self-report and recall bias may have influenced the results.MethodsWe investigated agreement between self-reported and recorded vaccinations and the relationship with health status in Australian Gulf War veterans.ResultsAgreement between self-reported and recorded vaccinations was highest for plague (kappa = 0.80), and kappa coefficients were greater than 0.60 for polio and ‘other unlisted’ vaccines, between 0.41 and 0.60 for hepatitis B, hepatitis A, typhoid and pertussis, and less than 0.40 for the other listed vaccines. The associations of increasing number of self-reported vaccinations in dose response relationships with total number of symptoms, functional impairment, and poorer physical health were not observed when based on recorded vaccination data, although the actual difference in estimates was small and statistically significant only for total number of symptoms.ConclusionsVaccinations were not associated with adverse health effects when exposure assessment was based on recorded vaccinations. It would be prudent that future research studies should be based on recorded vaccination data.