See also the health economic study selection flow chart in Appendix D. 6.1.1.5 Evidence statements Clinical Two studies were identified for inclusion within the review. The quality of the evidence ranged from low to very low due to risk of bias, imprecision due to wide confidence intervals surrounding the effect estimate and indirectness of the study population. One study including 38 people with HFREF or HFPEF on optimally tolerated medical therapy with normal serum sodium compared a moderate salt intake (2300mg/day sodium) with low salt intake (1500mg/day sodium). In reality, participants in either arm reduced salt to a relatively similar extent (median difference 63mg/day). The outcome QoL (as measured by the KCCQ) showed a clinically important reduction in quality of life with the low sodium diet. The low sodium diet also showed no clinical effect on renal function. Imprecision could not be assessed for these outcomes as the study reported the results as median and interquartile range. The results of this pilot study were used to inform the larger SODIUM-HF trial, which is currently recruiting The second study which included 25 people, who were already enrolled in a trial of an intrathoracic impedance monitoring device and who had been hospitalised within the previous 6 months, compared an education programme providing support to maintain fluid restriction at 1.5-2L (intervention) with general support unrelated to the fluid restriction (control). The outcome QoL (as measured by the EQ5D VAS) showed a clinically important reduction in quality of life with the fluid restriction programme (associated with wide confidence intervals around the effect estimate). The fluid restriction programme had no clinical effect on the outcome oedema (again associated with wide confidence). Economic No relevant economic evaluations were identified. Chronic Heart Failure Beta-blockers in heart failure and concomitant atrial fibrillation NICE 2018. All rights reserved. 