Really, really, the last thing I want to write on OFA testing.

I have SO MUCH more to write about and think about and wrestle with than this topic. I hate the fact that it becomes The Thing instead of only a thing, most correctly a small thing. It’s like yelling “A! A! A! A!” and leaving off the rest of the alphabet. So I will continue to respond to comments or questions about hip testing but I don’t intend to write many more posts about it. I have PLENTY that is controversial to talk about without ever mentioning hips again, trust me.

So here’s my last thing, what I’ve tried to make a distillation of the questions I am asking.

Let me suggest what may be a helpful analogy:

I am a pharmaceutical company bringing a blood pressure drug to market. This drug, as all drugs do, has side effects.

I must answer the questions “Does this drug lower blood pressure?” and “Do its benefits outweigh its risks?”

Both of those are medical and statistical questions. The drug must be proven to be significantly better than a placebo AND it must be proven that its benefits produce greater health in the population of people taking it than its risks hurt that population.

The answer to both must be yes. A drug can work but have such significant side effects that it is rejected, and a drug can be very safe but not actually work.

The answers to those questions are NOT any of the following:

“I know someone with high blood pressure.”
“I know a doctor who was sued because one of his patients has high blood pressure.”
“I think we need to care more about high blood pressure.”
“If we don’t control blood pressure, we’re going to lose our jobs.”

And, because anecdotal evidence must always bow to studies, the answer is also not any variation on the following:

“I know someone who took this drug and he was fine.” or “I really respect Dr. Smith and he prescribes this drug.”

Any or all of those may be true statements, but they have nothing to do with whether this drug should be approved.

Let’s apply that to what I am hoping is the question here: Does following OFA’s recommendations
lower the proportion of painful hip changes in our breed?

THAT’S the only question that is relevant. Because following it DOES have side effects–we cull certain dogs and we favor the genetics of other dogs. Those are powerful and potentially dangerous decisions, so we shouldn’t be making them if we get no benefit.

And we most definitely should not be making the use of this “drug” a condition for being called a reputable breeder.

So we need to stop responding to that question with “I know a dog with hip dysplasia” or “I think we need to care more about hip dysplasia” or “I got a dog from breeder X and she had hip dysplasia” or “we’re all going to get sued if we don’t eliminate hip dysplasia.” And we need to reject, as a justification, “I really respect breeder Y and she has always OFAd.”

The OFA self-reports a decrease in failing scores over the last 30 years. However, a careful reading of the statistics shows that the vast majority of the “improvement” was before 1990. Since 1990, which is at least six generations and in some breeds more like ten, most breeds have shown only a tiny improvement. That strongly indicates to me that between 1970-whatever and 1990 was when breeders were figuring out which hips would fail, and learning not to submit them. I could be wrong, but it’s pretty striking how the “improvement” abruptly slowed to a tiny trickle.

Since 1990 there’s been a small improvement in most of the breeds. However, that result is not “controlled.”

If I look in my kitchen and the floor is dirty, and then ten hours later the floor is clean, I can’t give my husband credit if I know that both my daughters, my mom, my best friend, and the US hockey team was also in my house in those ten hours.

Since 1990, we’ve used OFA. We’ve ALSO changed the way we feed, vaccinate, exercise, supplement, and so on. We’ve also gotten even better at not submitting films we believe will fail.

That’s why the only number you can trust is one derived from an experiment where it is absolutely known that there’s only one factor in play, only one person on the house with access to the mop.

Some Cardigans are dysplastic.
Some Cardigans have painful hip arthritis (note that this is not the same as the statement above).
We are pretty constantly in danger of being legislated out of breeding.
We have responsibilities to our eventual puppy buyers.

None of those statements are being debated here, and unfortunately none of are relevant. The ONLY thing that is in question is “Does following the OFA’s recommendations decrease the proportional amount of painful hip arthritis in our breed?”

The best study I can find, the only one that is controlled, says that the influence of OFA’s recommendations is not statistically greater than zero, even in long-legged breeds it was designed to fit. If it were a drug, it would be rejected as being no more effective than a placebo. And it has demonstrable side effects.
So you tell me. Why are we pushing this “drug” as a sign of “good breeding”?
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One thought on “Really, really, the last thing I want to write on OFA testing.

  1. Not submitting failing hip radiographs will obviously skew the findings with respect to hip dysplasia stats, however, there has beeen a huge increase in the number of excellent hips being rated in many breeds. No doubt mostly all passing rads are being submitted. This shows improvement in a positive direction, or at the very least that OFAing dogs can produce better grades within PASSING hips. Whether the rate of HD is being reduced is unknown with incomplete data. However, that may change in time with CHOC registry encouraging people to submit failures and more and more are doing so. Time will tell.

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