9 The evidence

Introduction

The evidence statements from 3 reviews are provided by the London School of Hygiene and Tropical Medicine.

This section lists how the evidence statements and expert papers link to the recommendations and sets out a brief summary of findings from the economic analysis.

How the evidence and expert papers link to the recommendations

The evidence statements are short summaries of evidence, in a review, report or paper (provided by an expert in the topic area). Each statement has a short code indicating which document the evidence has come from.

Evidence statement number 1.1 indicates that the linked statement is numbered 1 in review 1. Evidence statement number 2.1 indicates that the linked statement is numbered 1 in review 2. Evidence statement EP1 indicates that expert paper 1 is linked to a recommendation.

If a recommendation is not taken directly from the evidence statements, but is inferred from the evidence, this is indicated by IDE (inference derived from the evidence).

Recommendation 1: evidence statements 1.1, 1.11, 1.13, 2.10, 3.5; EP1, EP3, EP4, EP6, EP7

Recommendation 2: evidence statements 1.1, 1.10, 1.11, 1.12, 1.13, 2.10, 3.5; EP3, EP4, EP6, EP8

Recommendation 3: evidence statements 1.1, 1.10, 1.11, 1.12, 1.13, 2.10; EP3, EP4, EP5, EP6, EP8

Recommendation 4: evidence statements 3.2, 3.5; EP3, EP4, EP6, EP7

Recommendation 5: evidence statements 1.3, 1.6, 1.9, 1.12, 1.14, 2.1, 2.3, 2.7; EP1, EP2, EP3, EP4

Recommendation 6: evidence statement 3.5; EP4, EP6, EP8

Recommendation 7: EP4, EP6

Recommendation 8: evidence statement 3.5; EP4, EP6

Recommendation 9: evidence statement 3.5; EP4, EP8

Recommendation 10: EP4

Recommendation 11: evidence statements 2.6, 3.5; EP3, EP4, EP5, EP6

Recommendation 12: evidence statement 2.10; IDE

Economic modelling

Providing home heating and insulation interventions to households where someone has chronic obstructive pulmonary disease, heart disease or is older than 65 was found to be cost effective from the perspective of the health sector. (This assumes that the health sector does not bear the full costs of the physical changes to the building fabric.) In some cases, the full cost of the intervention could potentially be justified solely on the basis of the health benefits alone.

One of the key factors in determining cost effectiveness is whether the potential indoor air pollution caused by altering ventilation rates during energy efficiency upgrades can be avoided. (If ventilation is poor and this leads to health problems, the interventions will not necessarily be cost effective.)

The modelling compared programmes targeting low SAP homes where people were at risk of ill health with programmes aimed at all homes where people were at risk of ill health. The targeted approach was much more cost effective.

Fuel subsidies are less cost effective than home energy efficiency measures, but the former may be more suitable over shorter time frames. That's because they avoid a large capital investment cost for people who may have a comparatively short life expectancy, or who expect to move home in a comparatively short period.

Quantification of the risks and benefits associated with home energy efficiency and fuel subsidy interventions is based on a model involving a complex chain of assumed causal links. For some of those links, the evidence base is limited and the results should, therefore, be interpreted as indicative only. However, they do provide a guide to the relative merits of broad interventions.

The specific scenarios considered and the full results can be found in the economic modelling report.

  • National Institute for Health and Care Excellence (NICE)