The review was unable to formally assess heterogeneity of the results split by age due to reliance on aggregate data from one of the existing meta-analyses, but the low levels of heterogeneity in the overall (not age- stratified) results gave the committee some confidence that considering the trials together was a valid approach. Chronic Heart Failure Monitoring NICE 2018. All rights reserved. Subject to Notice of rights. ISBN: 978-1-4731-3093-7 Recommendations Consider measuring NT-proBNP (N-terminal pro-B-type natriuretic peptide) as part of a treatment optimisation protocol only in a specialist care setting for people aged under 75 who have heart failure with reduced ejection An assessment of possible sources of bias showed that the randomisation and allocation concealment was either unclear or inadequate in many studies. The level of missing data was also not clear for some of the included studies, and there was limited detail in the existing meta-analyses on how the authors minimised the effects of missing data. Together these factors led to a high risk of bias assessment for many of the outcomes, including the mortality and quality of life evidence. The assessment showed generally low risk of bias in the subset of studies that contributed to the age-stratified all- cause hospitalisation data. The confidence intervals around most of the effect estimates were relatively wide, which further reduced the overall GRADE quality rating for all outcomes (with the exception of quality of life and renal function) and reduced the committee s confidence in the evidence. In particular, adverse events were not consistently reported, with many results based on only one trial, resulting in particularly large confidence intervals around the estimates of effect for those data. 