Trade-off between net clinical effects and costs No previously published economic evaluations were identified for this review. The committee agreed that domiciliary oxygen therapy is likely to be expensive as it requires regular visits to deliver new tanks of oxygen and associated equipment, as well as safe installation, risk assessment and maintenance of the oxygen. In addition, people on oxygen therapy should be regularly reviewed to assess their oxygen levels. The clinical evidence suggested there was no clinically important effect on quality of life, although this was highly uncertain. Due to the poor quality of the clinical evidence the committee could not assess the cost effectiveness of domiciliary oxygen therapy in people with advanced heart failure. However, due to the potentially high cost, and the known risks of oxygen therapy (described in the trade-off between clinical benefits and harms above) the committee decided that long term oxygen therapy should not be routinely offered to people with advanced heart failure. Current practice is thought to be widely variable, but is not commonly used as part of routine care in people with heart failure. The committee considered that this recommendation would not substantially change current practice, but could lead to some small cost savings. Other considerations The committee felt that it was important to be aware that people with advanced heart failure with other comorbid conditions may benefit from oxygen therapy. Examples where this may be the case include chronic lung disease such as COPD (https://www.nice.org.uk/guidance/cg101), or patients with pneumonia or pulmonary embolism. In addition to this, people who are in the last weeks of life may find oxygen therapy of symptomatic benefit and comfort and should be referred to the care of the dying adult guideline (https://www.nice.org.uk/guidance/ng31). 