Age-based differences in the predictive accuracy of a one-size-fits-all risk-cutoff value in prenatal integrated screening for Down syndrome.

OBJECTIVE

The objective of this study is to assess variation in detection and false positive rates and adverse pregnancy outcomes across different age groups when a one-size-fits-all risk-cutoff value, such as 1/270, is used in integrated screening for Down syndrome.

METHOD: A Monte Carlo simulation was utilized to estimate the detection and false positive rates as well as adverse pregnancy outcomes.

RESULTS

Using a one-size-fits-all risk-cutoff value, such as 1/270, can result in considerably high variations in detection and false positive rates across maternal ages and lead to a higher than the minimum possible total number of adverse outcomes.

CONCLUSION

Our findings indicate that the one-size-fits-all risk-cutoff value of 1/270, commonly used in DS screening, should be revisited and alternative (possibly age-based) cutoff values and strategies should be considered. © 2017 John Wiley & Sons, Ltd.