Data on lifespan of over 11 million cats and dogs (Banfield Hospitals USA)

The information from this enormous study from Banfield Pet hospitals in the USA regarding the life expectancy for dogs and cats derived from clinical data, is very surprising to me. I've produced a little table below which summarises the data. There are two rather odd findings.

Firstly, the lifespan of cats is shorter than that of dogs according to this study which doesn't make sense to me. I have always thought that in general cats have longer lifespans than dogs but comparisons are hard to make due to different lifestyles. 

And secondly the lifespan of ideal weight cats is shorter than the lifespan of obese cats which certainly does not make sense in any shape or form.

I produce it here because the information is on the Internet and you can make what you will of it.

The study itself produces some very fine detailed information which you can read about by clicking on this link if you wish.

The advantages of this study is that the data set comprised 8.9 million dogs and 2.4 million cats which is more than 10 fold greater than the dataset used to generate life expectancy tables for Japanese dogs for example.

As I say above, I can't trust this information despite the enormous amount of information collected from this hospital chain.

They admit to limitations and "a degree of uncertainty of pet age for dogs and cats required as rescued animals or adopted from animal shelters and the inherent limitations of body condition scoring." My guess is that the info is unreliable 😒😢🙄 But maybe I am being too gung ho in saying that.

That would imply that a lot of the cats and dogs were adopted from animal rescue centres and these animals had non-specific ages. I assume that their ages were estimated but I don't know.

I have a better study on another page, on another website which shows that the Birman and the Burmese are the two cat breeds with the best life expectancies of the purebred cats. In both these cat breeds did better than random bred cats in terms of life expectancy but once again I find that information questionable.

And once again I am presenting it here because it might interest people despite my doubts.

It would seem that the one certainty which has been found in other studies is that female dogs and cats live longer than male cats and dogs and this is evident in the table below. I have another page on that topic on another associated website.

Companion animal	Life expectancy
All dogs	12.69 years
Mixed-breed dogs	12.71
All cats	11.18
Mixed-breed cats	11.12
Female dogs	12.76
Male dogs	12.63
Female cats	11.68
Male cats	10.72
Obese dogs	11.71
Overweight dogs	13.14
Ideal weight dogs	13.18
Overweight cats	13.67
Obese cats	12.56
Ideal weight cats	12.18

Citation: Life expectancy tables for dogs and cats derived from clinical data.

https://doi.org/10.3389/fvets.2023.1082102

P.S. please forgive the occasional typo. These articles are written at breakneck speed using Dragon Dictate. I have to prepare them in around 20 mins.