Statistically is the UK railway network now less safe?

positron said:

Well the railway definitely has a number they use, called the Value of preventing a fatality (VPF) the number in 2025 was £2,856,000 (happy to be corrected).

Click to expand...

APT618S said:

Interestingly that figure is significantly higher than what NICE (The National Institute for Health and Care Excellence) use to approve NHS treatment which is around the £25k-£30k per year or QALY (Quality Adjusted Life Year):

Changes to NICE’s cost-effectiveness thresholds confirmed

Changes to NICE’s cost-effectiveness thresholds confirmed

www.nice.org.uk

Given the average rail traveller probably has around 40 years ahead of them that would equate to just £1m - £1.2m.

Click to expand...

The difference between these two numbers is likely that the NICE Quality Adjusted Life Year (QALY) is their calculated value of the life to the individual, but the Value or preventing a fatality (VPF) will include the (average) cost of the consequences to the organisation as well as the QALY value to the individual. Fatal incidents will be very disruptive, so the VPF number will account for the cost of clearing and restoring the line, the emergency services activities, the legal costs related to the consequences, the costs to the RAIB and other investigative activity, and the lost revenue for the duration of the incident and recovery (the list is probably not exhaustive). Non fatal accidents also have a formalised value for prevention.

These values are calculated and set to allow the business case of safety improvements to be calculated and trade offs with other benefits made. For example, if a proposal to reduce the risks from over-speeding involved a slower approach to such junctions, the value of the safety benefit is a trade off against the extended journey time disbenefit, which can also be calculated using the Value of Time to determine whether it is reasonably practicable - the RP in 'ALARP' (As Low as Reasonably Practicable). In the UK the DfT publishes them as part of the Transport Analysis Guidance WebTAG:

This content contains guidance on the conduct of transport studies, supported by the appraisal, modelling and evaluation strategy for transport. The guidance includes or provides links to advice on how to:

• set objectives and identify problems
• develop potential solutions
• create a transport model for the appraisal of the alternative solutions
• how to conduct an appraisal that meets the requirements of the Department for Transport (DfT)

Projects or studies that require government approval are expected to make use of this guidance in a manner appropriate for that project or study. For projects or studies that do not require government approval, TAG should serve as a best practice guide.

Click to expand...

If I have time, I'll replace the above link with one to the specific section of the guidance...

notverydeep said:

The difference between these two numbers is likely that the NICE Quality Adjusted Life Year (QALY) is their calculated value of the life to the individual, but the Value or preventing a fatality (VPF) will include the (average) cost of the consequences to the organisation as well as the QALY value to the individual. Fatal incidents will be very disruptive, so the VPF number will account for the cost of clearing and restoring the line, the emergency services activities, the legal costs related to the consequences, the costs to the RAIB and other investigative activity, and the lost revenue for the duration of the incident and recovery (the list is probably not exhaustive). Non fatal accidents also have a formalised value for prevention.

Click to expand...

From the RSSB guidance I linked upthread: https://www.rssb.co.uk/-/media/Proj...ty-related-cost-benefit-analysis-guidance.pdf

Costs that can be included in a safety-related CBA
The table below captures the costs routinely included in industry CBAs to support SFAIRP judgements. The savings are used to offset the total cost figure used in the CBA.

Click to expand...

From the table that follows:

Cost: Avoided costs of accidents

Definition: A reduction in the cost of accidents that are mitigated by the measure

Examples: Avoided costs of asset damage and reinstatement

Click to expand...

Financial costs that would be incurred due to an accident that is avoided by a particular safety measure are offset against the costs of implementing that measure. If there is a net cost saving before the fatality and weighted injury costs are considered then the benefit to cost ratio goes negative.

So this can't explain the difference in the railways value of preventing a fatality from NICE's QALY. I don't know why they are different, but maybe because death from natural causes is seen as less shocking than deaths in an accident.

edwin_m said:

From the RSSB guidance I linked upthread: https://www.rssb.co.uk/-/media/Proj...ty-related-cost-benefit-analysis-guidance.pdf

From the table that follows:

Financial costs that would be incurred due to an accident that is avoided by a particular safety measure are offset against the costs of implementing that measure. If there is a net cost saving before the fatality and weighted injury costs are considered then the benefit to cost ratio goes negative.

So this can't explain the difference in the railways value of preventing a fatality from NICE's QALY. I don't know why they are different, but maybe because death from natural causes is seen as less shocking than deaths in an accident.

Click to expand...

If from true natural causes then that death is unlikely to result in legal and compensation costs.

The value per QALY used by NICE is essentially a cost-effectiveness threshold used as a rationing device when considering new drugs and medicines. I suspect many of the applications relate to drugs which improve quality of life somewhat for very large numbers of people (think particular brands of statins, blood pressure, thinners, anti-histamines etc). NICE uses higher values for drugs for treating rare life threatening conditions.

The value of preventing a fatality (VPF or VOSL) used in the transport sector includes a large component of the GDP costs (lost income) associated with fatalities and serious injuries. I suspect that this component is not included in the NICE values which are more like the value to the individual than the value to society.

The exile said:

If from true natural causes then that death is unlikely to result in legal and compensation costs.

Click to expand...

All deaths are likely to incur some cost for sorting out the estate, even if this is only the executor's time. But my point is that the railway guidance makes it explicit that the financial costs of the accident are not included in the figure for cost per fatality and weighted injury.