12/06/2026
It starts with a crash test dummy.
For decades, the standard crash test dummy used to design car safety systems was modelled on the average male body — the weight, the height, the proportions. Cars were tested for safety using that dummy. Safety ratings were issued based on that dummy. Millions of cars were sold on the strength of those ratings.
Women, on average, have different proportions. Different weight distribution. Different seated posture in vehicles.
When female crash test dummies were eventually introduced and studied, the data showed something that should have been obvious from the beginning: women were significantly more likely to be injured or killed in crashes that the male-modelled safety systems had rated as safe.
The cars weren't designed to be dangerous to women.
They were designed without women in mind at all.
That distinction — between deliberate exclusion and invisible exclusion — is the heart of what Caroline Criado Perez documented in her 2019 book Invisible Women: Data Bias in a World Designed for Men. It won the Royal Society Science Book Prize. It became an international bestseller. It changed how researchers, policymakers, and ordinary readers understood the architecture of a world they had always assumed was built for everyone.
It wasn't.
Invisible Women exposes the gender data gap — a gap in knowledge that sits at the root of perpetual, systemic discrimination against women, creating a pervasive but invisible bias with profound effects on women's lives. Carolinecriadoperez
The mechanism Criado Perez identified is what she calls the Default Male: the conscious and unconscious societal practice of treating men's bodies and experiences as the model standard, with women's bodies and experiences treated as abnormalities, niche use cases, or afterthoughts. American University
It sounds abstract. The examples make it concrete — and the examples are everywhere.
Smartphones were designed for average male hand sizes. The result is that the standard iPhone is difficult or impossible to operate with one hand for a significant proportion of women. Voice recognition software was trained predominantly on male voices and consistently performs worse for female ones. Piano keys were standardised to a width optimised for average male hand spans — quietly disadvantaging female pianists from the beginning.
These are not conspiracies. They are the predictable outputs of design processes that did not think to ask: does this work for women too?
The consequences range from inconvenient to fatal.
In medical research, women have largely been excluded from clinical studies and textbooks, leaving them chronically misunderstood, mistreated, and misdiagnosed. Heart attack symptoms present differently in women than in men — but the male presentation is the one taught in medical schools as standard. Women experiencing heart attacks are more likely to be sent home, told their symptoms are anxiety, told they are overreacting. Amazon
The data gap, in those cases, kills people.
Cities prioritise men's needs when designing public transportation, roads, and even snow removal, neglecting to consider women's safety or unique travel patterns and responsibilities. Amazon
When one Swedish city studied how people actually moved through their urban environment, they found that men typically made simple point-to-point commutes while women made complex multi-stop journeys — dropping children at school, visiting elderly relatives, running household errands — before arriving at their own workplaces. Snow clearance had historically prioritised main roads and commuter routes. When the city redesigned its snow clearance schedule to prioritise pedestrian paths and local routes first, injuries dropped significantly.
The original schedule had not been designed to disadvantage women.
It had been designed without asking how women moved.
The result was the same.
Criado Perez argues that women aren't being excluded intentionally — it is a natural outcome of men holding influential positions in government, business, and society, and defaulting, unconsciously, to their own experience as the universal standard. Readingraphics
That framing matters. It moves the conversation from accusation to systemic diagnosis. The problem is not that individual designers, researchers, or policymakers are malicious. The problem is that a world built primarily by one group, without systematically collecting data on the other, will inevitably — invisibly, persistently — serve that one group better.
The solution is also systemic: collect the data. Disaggregate it by s*x. Ask, at every design stage, whether this works for women too. Make the invisible visible.
Before Invisible Women, Criado Perez had already demonstrated what one woman armed with evidence and determination could accomplish. She successfully campaigned for women to be represented on British banknotes when all non-royal women were about to be removed from the currency. She campaigned for a statue of suffragist Millicent Fawcett in Parliament Square — the first statue of a named woman to stand there.
She was awarded an OBE for her services to gender equality.
She kept going.
Invisible Women was not a theoretical argument. It was a documented case — built on hundreds of studies across dozens of countries — that the world as currently designed is costing women their time, their money, their health, and their lives.
The data was always there.
Someone just had to make it visible.
