Optimizing an algorithm for the identification and classification of pregnancy outcomes in German claims data.

PURPOSE: For studying drug utilization and safety in pregnancy based on administrative health care data, the reliable identification and classification of pregnancy outcomes in the data is essential. We aimed to optimize an existing algorithm for the identification and classification of pregnancy outcomes in the German Pharmacoepidemiological Research Database (GePaRD) with a particular focus on births. METHODS: We reconsidered all codes used by the original algorithm and applied it to data of GePaRD from 2006 to 2014. Longitudinal records of pregnancies were used to identify targets for enhancing the algorithm's specificity. We checked the plausibility of the results, eg, regarding the age distribution of persons with pregnancy outcomes. Based on 20 longitudinal records of pregnancies, we compared the outcome classification by clinical experts with the results of the modified algorithm. RESULTS: Our algorithm identified 1 235 261 pregnancy outcomes in the database, with the majority (94%) being live births, classified as preterm (10%), term (78%), and (12%) births after the expected delivery date. The median age of pregnant women was 32 years (Q1 28; Q3 35). Implausible sequence of outcomes (for example, an induced abortion within a pregnancy categorized as ending in a live birth) were rare (0.03%). The case profile review by clinical experts resulted in the same outcome type and date as the algorithm in 95%. CONCLUSIONS: Our algorithm led to plausible results regarding the identification and classification of pregnancy outcomes. It will be an important foundation for studies on drug utilization and drug safety during pregnancy based on GePaRD.

Epidemiology of influences on the performance in broiler flocks--a field study in Germany.

To establish which factors influence performance and bird welfare during a fattening period and to identify those factors to be investigated during routine monitoring of farms by veterinary authorities, a questionnaire-based field study was conducted in districts of Lower Saxony, Germany, with the highest density of broiler chickens. Mortality and BW of farms with different stocking densities (≤33, 33.1-39, and >39 kg/m(2)) were investigated. Analyses of 79 farms with 176 stables and 634 fattening periods revealed that flock mortality and BW appeared to be greatly influenced by weather conditions and litter material. In general, it is an advantage to grow broilers under warm weather conditions. However, the longer the fattening period lasts the more important it becomes that the outside weather conditions are not too warm. Therefore, weather conditions should be considered when determining the length of the fattening period, especially before the background of the growing demands of broilers regarding ventilation, absorption of feces by the litter material, and so on. Apart from the length of the fattening period, the weather conditions determine the choice of the litter material, as well. Under cold-humid weather conditions, it is better to use litter material other than wood shavings. In particular in older buildings it is not possible to provide the required conditions, which results in a lower weight gain the longer the fattening period lasts. The study identified differences in the final BW of flocks, which indicate different (farm) management policies. Regardless of the underlying policy, the performance of a fattening period can be improved by optimizing the farm management according to the prevalent conditions. Future routine monitoring, which should be cost effective regarding personnel and finance, should be generally risk based and consider weather conditions, litter material, the age of the building, and the length of the fattening period.