| This thesis was an investigation into the association between vaccination and a first diagnosis of idiopathic immune-mediated anemia (IMA) in dogs, as well as the association between age, breed or sex and idiopathic IMA. Cases of IMA were described and differences between study populations were evaluated with respect to selected paraclinical variables. Finally, information was provided about record quality with respect to identifying and classifying the outcomes and exposures of interest.; Cases of idiopathic IMA, and controls with other clinical problems, were selected from 4 populations in Canada. Similarity of idiopathic IMA cases from all 4 populations was determined with respect to select paraclinical parameters identified upon initial presentation. Cases from all 4 populations were more similar than dissimilar.; Conditional logistic regression was used to model the relationship between 'month since vaccination' and a diagnosis of idiopathic IMA, controlling for age, breed and sex. Idiopathic IMA in dogs, ∃1 year of age, was not associated with vaccination within 6 months of their diagnosis compared to dogs with an admission to the teaching hospital or a submission to the commercial laboratory for other reasons (the referent group was dogs vaccinated more than 6 months prior to their admission or submission).; Dogs with idiopathic IMA were more likely to be <12 years of age compared to dogs with other clinical problems but the effect was not linear. Dogs with idiopathic IMA were more likely to be Cocker Spaniels, Miniature Schnauzers, Springer Spaniels, Shih Tzus, and crossbreeds. Dogs with idiopathic IMA were more likely to be female dogs. However, these associations were not the same in all 4 populations.; In this case-control study, demographic information from teaching hospital and commercial laboratory records was reliable, resulting in an error rate of much less than 10%. Vaccination information (apart from the date of last vaccination) from records was considered unreliable because, over 73% of the time, vaccination was not recorded annually by the regular veterinarian and there was no indication of client behaviour with respect to vaccination frequency. As well, vaccine brands typically were not recorded. |
