General suspected heart failure population BNP and NT-proBNP are used as a triage test, with people whose results are above a certain threshold being referred for echocardiography and specialist clinical assessment, following which a definitive diagnosis can be made. The committee noted that the threshold for referral to echocardiography and specialist clinical assessment in the 2010 guideline was 400 pg/mL. The committee agreed that from a clinical perspective, a lower test threshold would mean fewer patients with heart failure would have their diagnoses missed or delayed, avoiding unnecessary hospitalisations and mortality. However, the committee recognised that if the test threshold was set lower than clinically necessary, many people may be unnecessarily referred for echocardiography and specialist clinical assessment. This could cause unnecessary worry for people and their families, as well as delaying diagnosis of an true underlying condition, and having resource and economic implications (discussed below). The committee considered the clinical evidence with the aim to determine which NT-proBNP threshold was most appropriate for identifying patients who should be referred for echocardiography and specialist clinical assessment, focussing on sensitivity of the test. The pooled sensitivity at a threshold of 125pg/mL was 96% (72%-100%), at a threshold of 280pg/mL was 89% (41%-89%), and at a threshold of 400pg/mL was 79% (42%-96%). The committee noted that the pooled evidence was very low quality due to inconsistency between the included studies and consequently very wide confidence intervals around the meta-analysed data. At a threshold of 400pg/mL, the committee also noted that specificity was likely to be much higher (82% (52%-95%)) compared with specificity at the which would reduce any clinical harms of over-referral. 