Supplementary Material for: Prevalence of Cerebral Palsy in Quebec: Alternative Approaches

<b><i>Aim:</i></b> To provide an estimate of the period prevalence of cerebral palsy (CP) in the province of Quebec. <b><i>Methods:</i></b> Children with CP were identified from three consecutive birth cohorts (1999–2001) from the Quebec CP Registry, covering 6 of the 17 administrative health regions of the province. Two inferential approaches were applied for period prevalence estimation, frequentist and bayesian. <b><i>Results:</i></b> 228 children were identified with CP. Using a frequentist approach, the overall prevalence of CP was 1.84 per 1,000 children aged 9–11 years living in those areas in 2010 (95% CI 1.60–2.08). Using a bayesian approach taking into account the uncertainty about the registry’s sensitivity in capturing all cases, the overall prevalence is higher at 2.30 per 1,000 children with a 95% CI (1.99–2.65). <b><i>Conclusion:</i></b> Using a bayesian approach to adjust for the registry’s known high specificity and lower sensitivity, the prevalence estimate is in concordance with worldwide estimates and estimates using administrative databases in western Canadian provinces. Future studies are needed to validate the diagnosis of CP within administrative databases and to evaluate possible regional trends across Canada in both prevalence and health service utilization, which may highlight disparities in healthcare delivery.