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

Aim: To provide an estimate of the period prevalence of cerebral palsy (CP) in the province of Quebec. Methods: 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. Results: 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). Conclusion: 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.

研究目的：估算魁北克省（Quebec）脑性瘫痪（cerebral palsy, CP）的时期患病率。
研究方法：从魁北克脑性瘫痪登记库（Quebec CP Registry）的3个连续出生队列（1999–2001年）中筛选脑性瘫痪患儿，该队列覆盖该省17个行政卫生区域中的6个。本研究采用两种推断策略开展时期患病率估算：频率学派（frequentist）方法与贝叶斯（bayesian）方法。
研究结果：共计识别出228名脑性瘫痪患儿。采用频率学派方法估算，2010年居住于上述区域的9–11岁儿童中，脑性瘫痪总体患病率为1.84/1000（95%置信区间（confidence interval, CI）：1.60–2.08）。考虑到登记库在捕获全部病例时存在敏感性不确定性，采用贝叶斯方法估算的总体患病率更高，为2.30/1000，95%置信区间为1.99–2.65。
研究结论：通过贝叶斯方法校正登记库已知的高特异性与较低敏感性后，本次患病率估算结果与全球范围内的相关估算结果，以及加拿大西部省份利用行政数据库得到的估算结果均保持一致。未来需开展相关研究以验证行政数据库中脑性瘫痪诊断的准确性，并评估加拿大全国范围内患病率与医疗服务利用情况的潜在区域差异，这有助于揭示医疗服务供给环节的公平性失衡问题。