All Wales Injury Surveillance System revised: development of a population-based system to evaluate single-level and multilevel interventions.

BACKGROUND: Injury surveillance has been established since the 1990s, but is still largely based upon single-source data from sentinel sites. The growth of electronic health records and developments in privacy protecting linkage technologies provide an opportunity for more sophisticated surveillance systems. OBJECTIVE: To describe the evolution of an injury surveillance system to support the evaluation of interventions, both simple and complex in terms of organisation. METHODS: The paper describes the evolution of the system from one that relied upon data only from emergency departments to one that include multisource data and are now embedded in a total population privacy protecting data linkage system. Injury incidence estimates are compared by source and data linkage used to aid understanding of data quality issues. Examples of applications, challenges and solutions are described. RESULTS: The age profile and estimated incidence of injuries recorded in general practice, emergency departments and hospital admissions differ considerably. Data linkage has enabled the evaluation of complex interventions and measurement of longer-term impact of a wide range of exposures. CONCLUSIONS: Embedding injury surveillance within privacy protecting data linkage environment can transform the utility of a traditional single-source surveillance system to a multisource system. It also facilitates greater involvement in the evaluation of simple and complex healthcare and non-healthcare interventions and contributes to the growing evidence basis underlying the science of injury prevention and control.

Unusual trend in the prevalence of trisomy 13 in mothers aged 35 and older: A population based study of national congenital anomaly data.

BACKGROUND: Trisomy 13 is one of the three autosomal trisomies compatible with viability. It is associated with structural anomalies, learning disability and poor survival. Advanced maternal age is the most frequently suggested risk factor. This is a population based register study to investigate the temporal trends of trisomy 13. METHODS: Chromosomal trisomies were reviewed by the Welsh Congenital Anomaly Register using data from 1998-2012. All pregnancy outcomes were included. Prevalence rates and trends for all cases and for cases with mothers aged below 35 years and those aged 35 years and older were plotted for trisomy 13, 18 and 21. Possible risk factors contributing to the trend in older mothers were compared in the early and late period of the study. RESULTS: There were 124 cases of trisomy 13 over the 15 year period with 55 mothers aged 35 years and older. Overall prevalence was 2.5 per 10,000 total births. A significant declining trend in the prevalence of trisomy 13 in mothers aged 35 and older (χ(2) trend = 4.98, p=0.026) was noted. Rates for younger mothers were lower and remained stable. Prevalence of trisomy 18 and 21 in older mothers remained stable. CONCLUSION: The unexpected declining trend in trisomy 13 in older mothers could not be explained by the risk factors examined in this study. There have been no other reports of trends in the prevalence of trisomy 13 in older mothers in recent years. There is further need for surveillance of trends in future and in other populations.