What do snow plowing patterns have to do with gender? A lot, as it turns out.

A number of municipalities in Sweden have evaluated their practice of first plowing major highways, then large surface streets and finally, side streets, walkways and bike paths. Pretty typical. But then they took a closer look at the data.

What they found was that women had markedly different driving patterns than men and were also much more likely to walk, often with children in tow, along snowy sidewalks. The women were much more likely to drive on the side streets getting children to and from school or daycare, running household errands and checking on elderly family members, then the men who typically drove on large surface streets to major employment areas and back home.

They also found that there were three times as many people injured while walking in icy conditions (again, predominately women) than there were injuries sustained while driving on icy roads.

Numerous municipalities in Sweden have reversed the order in which they plow the streets and neighborhoods and have seen a corresponding drop in mishaps and emergency room visits.

The original plowing plan was not designed to harm women, of course. It was seen as a neutral, common sense choice, one that made logical sense. But, through collecting and analyzing additional data, it became clear that the original decision had a decided, although invisible, gender bent.

Caroline Criado Perez’s latest book, “Invisible Women: Data Bias in a World Designed for Men,” lays bare some of the many ways that women have been and are, invisible.

She says: “Starting with the theory of Man the Hunter, the chroniclers of the past have left little space for women’s role in the evolution of humanity, whether cultural or biological. Instead, the lives of men have been taken to represent those of humans overall. When it comes to the lives of the other half of humanity, there is often nothing but silence.”

Just like snow plowing roads for the “default male,” there are almost endless examples of how men are seen as the example for humankind. Car crash dummies? Male. Heart attack symptoms? Male. Drug testing? Almost exclusively done on men. A decades-long longitudinal study on aging? 1,000 men, zero women.

How about the “standard office temperature”? Turns out that the formula used to calculate the ideal setting on the thermostat was a formula developed in the 1960s — based on the metabolic resting rate of the average man. A 2015 Dutch study found that the formula overestimates female metabolic rates by as much as 35% — resulting in offices that are too cold for female workers.

While some of these data biases are inconvenient — cold offices, cupboard shelves that are too high, tools too big to fit comfortably in female hands — some are downright deadly. Women having heart attacks have been mis-diagnosed for years because their presenting symptoms are quite different from men’s. The most frequently reported symptom in a 2003 study, for example, was not chest pain, but “unusual fatigue, sleep disturbances and anxiety,” with nearly 80% reporting that they had experienced at least one symptom for more than a month before their full-blown heart attack. And the advice that taking low-dose aspirin could reduce your risk for heart disease? That was based on a study of 22,000 men — and zero women.

Men are more likely to be in a car crash, but when a woman is in a crash, she is 47% more likely to be seriously injured, 71% more likely to be moderately injured and 17% more likely to die. Why? Because cars are designed for the “average” male — taller and heavier than the average woman. It was not until 2011 that the U.S. started using a female test dummy — but instead of actually making a representative model, manufacturers just scaled down the male version. And almost all tests put her in the passenger seat.

For most of recorded history, humankind has told only half the story. It’s way past time to tell the whole story.

| Courtesy Holly Richardson, op-ed mug.

Holly Richardson is a regular contributor to The Salt Lake Tribune.