The Office for National Statistics (ONS) has confirmed that the 2021 census may have overestimated the number of transgender individuals in the UK because of some respondents misunderstanding the question, the BBC reports.
The census indicated that approximately one in 200 people aged over 16 identified as a different gender from their sex at birth.
However, a subsequent review revealed that individuals who do not speak fluent English might have misinterpreted the census question and incorrectly identified as transgender. Despite earlier defense of its methodology by the ONS, concerns about its accuracy had been raised by some academics.
In the 2021 census, residents of England and Wales were asked: "Is the gender you identify with the same as your sex registered at birth?" The ONS reported that 262,000 people—about 0.5% of the population—answered "no."
On Wednesday, Mary Gregory, a deputy director at the ONS, suggested that some individuals might have misunderstood the question. On the ONS's website, she noted that there was "potential bias" in responses from those with lower levels of English proficiency, some of whom may have inadvertently indicated they were transgender.
Gregory acknowledged that the number of mistaken responses was likely "relatively small" but significant enough to distort the data in areas with higher numbers of non-English speakers.
In April, Michael Biggs, a professor of sociology at Oxford University, publicly questioned the census statistics. Writing in the British Sociological Society journal, he observed that a disproportionate number of those recorded as transgender did not speak English (or Welsh in Wales) as their first language. While only 10% of respondents reported not speaking English as their main language, they constituted 29% of the transgender population, according to Prof. Biggs.
For instance, the London Borough of Newham, which had the highest proportion of people identifying as transgender (1.51%), also has one of the highest rates of non-English speakers—35%, compared to 9% nationally.
In response, the Office for Statistics Regulation has reclassified the data from "accredited official statistics" to "official statistics in development" to reflect these potential issues. However, the regulator affirmed that other statistics from the 2021 census remain fully accurate.
The ONS had previously claimed that its estimates of the transgender population were consistent with “international comparators.”