An article in the Guardian reports this headline:
Women 32% more likely to die after operation by male surgeon, study reveals
The author of the original report also claims:
In our 1.3 million patient sample involving nearly 3,000 surgeons we found that female patients treated by male surgeons had 15% greater odds of worse outcomes than female patients treated by female surgeons
Which sounds less bad that the death ratio but might be explained by measuring a much wider range of outcomes than death.
The original study is reported in JAMA Surgery.
There are some reasons to be skeptical. Not least other reported results on similar issues show small effects (this question Are female surgeons less likely to kill you? referenced a study that reported much smaller differences, for example). And death rates are generally low making conclusions on the relative change in rates less reliable and potentially more subject to confounding. And is the difference in mortality consistent with the differences in other outcomes? And, what are the error bars on the result (the media reports leave that sort of important information out)?
So is it true in general that female surgeons do a better job operating on women than male surgeons? Or is this study a one-off anomaly? Is it merely an accidental correlation and not a causal effect?