Multiple vaccinations, health, and recall bias within UK armed forces deployed to Iraq: cohort study.
OBJECTIVE
To assess the relation between self reported number of vaccinations received and health, and between numbers of vaccinations recorded from individuals' medical records and health.


METHODS
First phase of a cohort study.


METHODS
UK armed forces personnel.


METHODS
4882 randomly selected military personnel deployed to Iraq since 2003 and a subset of 378 whose vaccination records were accessed.


METHODS
Psychological distress, fatigue, symptoms of post-traumatic stress disorder, health perception, and multiple physical symptoms.


RESULTS
Personnel who reported receiving two or more vaccinations on a single day were more likely to report symptoms of fatigue (adjusted risk ratio 1.17, 95% confidence interval 1.05 to 1.30), show caseness according to the general health questionnaire (1.31, 1.13 to 1.53), and have multiple physical symptoms (1.32, 1.08 to 1.60). These associations were no longer significant when number of vaccinations recorded in individuals' medical records was used as the independent variable.


CONCLUSIONS
Multiple vaccinations given to personnel in the UK armed forces in preparation for deployment to Iraq are not associated with adverse health consequences when vaccinations are recorded objectively from medical records. Adverse health consequences associated with self reported multiple vaccinations could be explained by recall bias.
Murphy
Dominic
D
King's Centre for Military Health Research, King's College London SE5 9RJ. dominic.murphy@iop.kcl.ac.uk
Hotopf
Matthew
M
Wessely
Simon
S
D000328:Adult; D015982:Bias; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007493:Iraq; D054542:Iraq War, 2003-2011; D008297:Male; D008603:Mental Health; D011939:Mental Recall; D008889:Military Personnel / Q000523:psychology / Q000706:statistics & numerical data*; D006113:United Kingdom; D014611:Vaccination / Q000523:psychology / Q000706:statistics & numerical data*