NPPB and hydrops fetalis: The current results using primary care data are consistent with the findings of a large systematic review of NP testing for chronic HF across ambulatory settings, published in 2018.18 The review included 39 diagnostic accuracy studies of NP testing, five of which were conducted in primary care and reported a pooled sensitivity of 95% (95% CI = 90 to 98) for the BNP ≥100 pg/mL referral threshold, very similar to the current study, but with no difference between BNP and NT-proBNP test performance overall.