Review Warns of the Risks to Health Care and Justice Posed by Flawed Biological Sex Data in Public Records
Research indicates that the confusion between ‘sex’ and ‘gender’ in public records is impacting the reliability of government data.
According to an independent review, recording public sector data based on self-declared gender identity rather than biological sex could have significant consequences for health care and criminal justice.
“This is especially evident within health and social care, with minors being particularly vulnerable,” the review stated.
The review highlighted that NHS records tend to focus on gender identity rather than biological sex, leading to some patients missing essential health screenings such as cervical smear tests or prostate exams. In certain cases, this approach led to delays in cancer diagnoses.
Laboratory results were also misinterpreted due to the absence of sex-based data, resulting in inaccurate medical evaluations. The report emphasized that this poses a “serious safeguarding risk,” particularly for children and vulnerable patients.
To address this issue, the review recommended that the NHS refrain from altering a person’s recorded sex after gender surgery and instead consider recording both sex and gender identity separately for patient safety.
This practice of recognizing sex in data collection does not diminish respect for individuals’ gender identity, as per Streeting, who affirmed that the government will take action.
Concerns in Justice and Crime Data
Some police forces categorize crimes committed by male suspects as female offenses if the suspect identifies as a woman, potentially inflating female crime rates, according to the review.
There are also concerns in police investigations where officers may not be aware of a suspect’s criminal history if their sex has been changed in police databases, possibly resulting in offenders being released without proper scrutiny.
For example, Police Scotland confirmed that if a male suspect who identifies as a woman commits a crime like rape, it would be classified as a female offense.
The review also noted that certain government surveys, like the Royal Navy Sexual Harassment Survey, do not inquire about biological sex, only gender identity.

A registration form and a stethoscope at the Temple Fortune Health Centre GP Practice near Golders Green, London, on Sept. 10, 2014. Anthony Devlin/PA
Similarly, the NHS Staff Survey ceased collecting sex data in 2017, instead offering options like “non-binary” or “prefer to self-describe.”
To tackle these challenges, the review recommended that the home secretary mandate all police forces to include biological sex in crime data.
Evolution in Data Collection Practices
The report illustrated how data collection has evolved over the last 30 years.
In the 1990s, “gender” began replacing “sex” in records, with many organizations in the past decade combining sex and gender identity questions or substituting sex-based queries with gender identity ones.
The team led by Sullivan found that while some surveys still categorize sex as “male” or “female,” they also offer additional choices like “other.”
The report emphasized that this goes against official data standards, which advise against using sex and gender identity interchangeably.
Maya Forstater, CEO of the charity Sex Matters, commented that the review clearly demonstrates the harm caused by mishandling sex data.
“The issues span from NHS records that ignore biological sex to police forces labeling male sex offenders as women. Conflating sex and gender identity is not an act of kindness but a failure of duty,” Forstater added, urging the government to implement the review’s recommendations.
A government spokesperson highlighted the importance of accurate and relevant data collection, particularly concerning sex, for public services.
“We appreciate Professor Sullivan’s work, which has been shared with relevant government departments and public organizations, including the ONS [Office for National Statistics],” the spokesperson concluded.
PA Media contributed to this report.