This article is more than 7 months old

This article is more than 7 months old

A national survey of rail passengers that has guided UK decisions on rail franchising for two decades has been condemned in a highly critical report by the statistics regulator.

The Office for Statistics Regulation said the national rail passenger survey (NRPS) was not yet fit to be designated as an official national statistic.

Writing to the passenger watchdog, Transport Focus, which compiles the biannual survey, the regulator warned there was “a substantial risk of misinterpretation and misuse” of the statistics.

The OSR’s director general, Ed Humpherson, said: “Statistics that inform and drive improvements across the rail network across Great Britain really matter and it is important that they are accurate, quality-assured and reflect the everyday experience of rail passengers. It is our view that statistics derived from the NRPS do not currently meet these expectations.”

The survey provides headline scores of passenger satisfaction with the railways, based on their last journey, allowing for comparisons by train operator. It also shows detailed changes in satisfaction with aspects of the journey, including value for money and onboard amenities.

Humpherson told the Guardian he was concerned that weight was being put on the survey results that, “within their parameters”, they could not really bear, adding: “Our primary concern is that the survey isn’t reflecting public passenger experience of rail travel.”

He said the survey only provided snapshots by inquiring about the last completed journey, and sampling only in spring and autumn, often outside key periods when passengers experience disruption that would negatively affect their experience.

Transport Focus, which had approached the regulator to conduct the assessment, said it welcomed the report, “which acknowledges our efforts to continuously improve and innovate”. The watchdog’s chief executive, Anthony Smith,said the survey led “the debate with the passenger’s voice”, but agreed that its accuracy would be improved if it was carried out throughout the year.

Smith said year-round polling would require approximately three times the £800,000 a year the survey receives from the Department for Transport.

A DfT spokesperson said: “We will work with Transport Focus to help it meet the recommendations set out in the report.”