Britain’s statistics quango faces an official investigation over a faulty census question which appears to have drastically overestimated the number of trans people in the country.
A campaign group has written to a watchdog to demand it take regulatory action in order to secure public confidence in national statistics.
They said action was required to ensure the faulty question is not replicated in future years.
It comes after the 2021 census in England and Wales reported there were 262,000 trans people, equivalent to 0.5 per cent of the population.
It was the first time the survey had asked whether people identified as a gender that was different from their registered birth sex.
The Office for National Statistics (ONS) has admitted there were “patterns in the data consistent with some respondents not interpreting the question as we had intended”.
The ONS census asked: “Is the gender you identify with the same as your sex registered at birth?”
People whose first language was not English were four times more likely to say they were trans than those with English as their main language.
It led to anomalies such as a greater proportion of people in the London boroughs of Newham and Brent declaring themselves trans, than in places such as Brighton.
Despite this, the ONS declared it still had “confidence in the gender identity estimates as a national level”.
‘The data on gender identity are worse than useless’
The gender-critical group Sex Matters has written to Ed Humpherson, the head of the Office for Statistical Regulation, to demand an investigation.
Maya Forstater, its executive director, also called for the Commons public administration and constitutional affairs committee to open an inquiry into what went wrong.
She said: “Despite warnings from many that its questions and guidance on sex and and gender identity were confusing, and the categories were muddled, the ONS bullishly went ahead with them in the census. This was a costly mistake.
“The resulting data on gender identity are worse than useless, as they give the impression of certainty and detail on which decisions can be made.
“The ONS has dug in and refused to admit that this data is unreliable, so we are calling on the national statistics regulator to properly investigate and determine whether they meet the grade for national statistics.”
ONS investigation ‘undermined confidence in national statistics’
In their letter, the group said: “Our conclusion is that data on gender identity (including the sex of the people identified as transgender) is not fit for purpose.
“It was driven by the adoption of concepts and questions promoted by lobby groups that seek to replace sex with gender identity.
“This investigation by the ONS is inadequate and undermines confidence in national statistics. It lays the groundwork for further erosion of clarity on sex, and the wider adoption of a gender identity question, and use of associated data, that has been demonstrated to be unreliable.
“The ONS has proved itself unwilling to accept clear indications that the gender identity question produced unreliable answers.
“We call on the Office for Statistics Regulation to take regulatory action in order to secure public confidence in national statistics, and to prevent the faulty question being replicated.”
They said the question on gender identity should be removed from future censuses, “with an apology and an explanation to discourage others from using the same wording”.
They added that a warning should be put on the data, that it should not be designated as national statistics, and the ONS definition of “sex” must be changed to mean biological sex.
The letter is signed by Ms Forstater along with Helen Joyce, Sex Matters’ director of advocacy, and Michael Biggs, an advisory group member.
The ONS was approached for comment.