[jedberg]

> I was not expecting that the median threshold (hue 174) would be so deep into the greens.

You're not asking gender of the test taker. Your results will be skewed because you're probably getting more men than women. Women in general have more ability to detect green vs blue.

[dentemple]

Even more fundamentally, red-green colorblindness is a recessive trait on the X chromosome, thereby affecting biological males in far greater number than females.

It could be a high enough percentage to make the results from this site noticeably different between the sexes.