Biotech Values

[biomaven0]

>>Ownership of a mixed-breed dog was associated with higher risk of CVD

Bingo.

Strongly suggests that there is a confounder here - likely wealth or socioeconomic status - that they haven't properly accounted for.

And of course the possibility of reverse causation that has been previously suggested here (if you are frail or perhaps very obese you are less likely to get a dog) is also lurking. And the multiplicity is of course another worry.

The twin part of the study was likely too underpowered to conclude much.

Peter