alphaOutcome allows you to access the αlpha database and to specify the outcomes of all pregnancies screened, and to record details of the presence or absence of birth defects. It provides a range of audit facilities which are useful in monitoring screening performance.
For example, with alphaOutcome you can:-
- Produce summaries of pregnancies with specified abnormalities, according to the screening result
- Print a list of screened pregnancies whose outcomes are not yet known, according to the date of screening or the expected date of delivery
- Examine the uptake of different prenatal diagnostic procedures, according to the screening result
- Compare the observed risk of Down's syndrome (determined after the outcome of pregnancy is known) with the risk predicted by αlpha
Recording the pregnancy outcomes
The figure below shows a pregnancy outcome being recorded in Outcome. The 10th Edition of the International Classification of Diseases is used to classify the birth defect.
The figure below shows an Outcome screening audit. Summaries of pregnancies with specified abnormalities can be made.
Validating a screening program using αlpha Outcome
Studies have demonstrated that risk estimates for Down's syndrome produced by αlpha are accurate (see references). Now αlpha users can perform this validation for themselves provided a sufficiently large number of women have been screened. This technique is a complete validation of the screening method.
The figure below shows a validation plot for a screening program. The graph shows the observed prevalence of Down's syndrome according to the median risk in groups of pregnancy ranked by the predicted risk. The diagonal line represents perfect agreement between the predicted risk of Down's syndrome and the birth prevalence of Down's syndrome in the absence of screening.