EPIDEMIOLOGIC RISK-FACTORS ASSOCIATED WITH A DIAGNOSIS OF CLINICAL CYATHOSTOMIASIS IN THE HORSE

Multiple logistic regression was used to assess epidemiological risk f actors associated with the diagnosis of cyathostomiasis in 87 cases of chronic diarrhoea in the horse. Age, season and the period since last receiving anthelmintics were identified as important risk factors usi ng chi-square and two-sample t test analyses, whereas access to grazin g, shared grazing with other horses and recurrence of signs were only weakly associated with a diagnosis of cyathostomiasis. Multivariate an alysis of the parameters using logistic regression was performed. The final model included age, season and time since last deworming. At a p redicted probability of cyathostomiasis of 0.5, the model had a specif icity of 86.0%, sensitivity of 66.7%, overall correct classification o f 79.3%, a positive predictive value of 71.4% and a negative predictiv e value of 83.1%. The results of this study indicated that the specifi ed variables and factors may be useful in the differentiation of clini cal cyathostomiasis from other causes of chronic diarrhoea, based on c ase history alone.