In response to a 2013 question from a reader, I blogged about the complete lack of evidence that OR staff hair caused wound infections or any other problem. After a similar question from another reader three years later, I pointed out nothing had changed.
Finally a 2017 paper in the journal Neurosurgery appeared online comparing the incidence of wound infections in clean cases for the 13 months before and the 13 months after the institution of a ban on the wearing of the traditional surgeons’ ca`p. Over 15,000 patients were included in the study which found no statistically significant difference in the rate of wound infections.