PennHIP vs. OFA: Better medicine vs. better marketing
It’s like VHS over Betamax, the US standard microchips vs. the world’s ISO, the PC’s dominance over the Macs’ operating system, the Kwerty keyboard over other more intuitive models…
Though you may disagree with me on some of the above examples, the history of technological standards is littered with ways in which arguably far better models lost out over their lesser rivals. And it usually comes down to marketing.
Sometimes it means getting government to buy into one standard over the other, distributing your model at a low cost to a high-use industry (reference porn and VHS) or shouldering out competitors with disingenuous practices (á la AVID microchips). Sometimes it’s just a matter of marketing-dedicated dollars and a nimble marketing arm (Microsoft vs. Mac).
Where am I going with this? For those of you whose breeds are predisposed to hip dysplasia, you might know that the OFA (Orthopedic Foundation for Animals) and PennHIP models represent rival technologies for assessing dog hips. You should also know that I consider the PennHIP model superior.
No, it’s not because I went to the University of Pennsylvania and had this method drummed into me (indeed, they did almost no chest-beating on this issue while I was there). And it’s not because Dr. Gail Smith, the veterinary surgeon originator of the PennHIP approach, was a popular prof there.
Nope. It’s because I believe that any rational person who would compare the two technologies would be hard-pressed to side with the OFA method. Here’s why:
PennHIP patients’ X-rays are assessed via objective measurements while the OFA X-rays are graded by a small panel of radiologists based on subjective impressions of the dogs’ individual hip conformation.
PennHIP requires any veterinarian who undertakes this method to have his or her X-rays included in a database of cases, regardless of hip quality. This improves not only the value of the database but its value to dogs at large for its more accurate representation of the real incidence of hip disease. Result accuracy for individual dogs are continually refined as more enter the database.
The OFA’s approach effectively allows veterinarians to select the best images or decline to submit poor quality hips for evaluation, thus skewing their database towards better hips. This selection bias renders this database somewhat useless.
3. Early prediction of future disease
The OFA method does not purport to accurately predict future disease. Moreover, it cannot be undertaken until an animal is two years old and well into its breeding years. This means that many dogs will enter the show ring before its hips are evaluated, thus increasing the chance that poor hips will enter the genetic pool through award-based incentives.
PennHIP can be employed as early as 16 weeks for an accurate prediction of future changes to the hips. Therein lies its most valuable asset: its ability to eliminate hip dysplasia entirely from the genetic pool if everyone used this method on their pre-pubescent dogs.
But PennHIP does have some downsides and detractions. Here’s a run-down of these:
OFA can be used by any veterinarian with an X-ray machine while PennHIP vets must be certified after completing a one to two day course. In my area (Miami) only one vet is certified. I counted about 25 PennHIP veterinarians in the whole state of Florida.
OFA requires a simple fee for evaluation and certification on one X-ray. If the hips are judged obviously poor by the general practitioner veterinarian taking the X-ray, many elect not to send in the film and incur an additional expense. Many vets don’t sedate or anesthetize for this X-ray (though I do).
PennHIP requires the dog’s owner to commit to the entire service: anesthesia, three X-rays and the evaluation fee. Tack on any additional fees to reimburse the veterinarian for his or her certification status and you’ve got a pricier procedure, sometimes two to three times what OFA costs.
I’ve already mentioned this one but it deserves a special mention for those who choose to limit their dogs’ anesthetic experiences. While I would not undertake OFA X-rays without anesthesia or sedation, many vets do. Dog owners unwilling to have their dogs anesthetized can usually find veterinarians to perform drug-free OFA X-rays. Not so for PennHIP.
OFA says PennHIP causes pain while the animal’s limbs are submitted to the more natural weight-bearing position required for these X-rays. But PennHIP denies this, citing only a handful of cases where patients were more than minimally lame for a day or more (with no lasting discomfort for any). I can’t vouch for this, but I will attest to having some OFA patients experience some discomfort after their X-rays if their hips were poor.
(To check out what the different styles of X-ray positioning looks like, check out this previous post of mine.)
For me, it seems the OFA procedure is so inferior a method that if we were comparing treatment regimens instead of diagnostics, there would be little doubt that the newer, pricier model would have been overwhelmingly accepted years ago as the ideal alternative. But it’s not.
Hip replacements over FHOs, TPLOs over extra-capsular repairs, cyclosporine instead of perianal fistula surgery, hyposensitization over serial steroid therapy…
These are some off-the-top-of-my-head examples of where more expensive therapeutic regimens won out in favor of far less effective methods. In fact, it would be fair to say that NOT offering the more effective choice in these cases could be construed as malpractice…or at least as depriving clients of their right to informed consent.
Not so with PennHIP. The minimal access clients have to this superior diagnostic tool (at least in my area) means that veterinarians are justified in ignoring its clear superiority in favor of the more accessible, less expensive alternative.
If I were to give Dr. Gail Smith some unsolicited advice for his PennHIP program, from one marketing-minded veterinarian to another, I’d…
1. ...infuse his not-for-profit program with enough emergency donor cash to increase the marketing and distribution of his course.
2. ...reduce the barriers to entry for veterinarians (like me) who want to play but find few opportunities to do so at my local conferences.
3. ...minimize the evaluation cost for each patient submission.
4. ...market my method to savvy pet health insurance providers who have incentives to better understand the hip risk each patient faces.
5. ...make sure every veterinary student left vet school knowing which method was best. After all, when even Penn vets like me leave school with a fuzzy idea as to whether PennHIP is really superior or not, you can’t expect veterinary graduates of other programs to know any better.
6. ...enlist breed clubs, have a presence at major dog shows and write articles for pet owner publications (and blogs like this one) to raise demand for the service at it's source: responsible dog owners.
These are just a few broad ideas. Sounds to me as if Dr. Smith could use a few students from across the street at Wharton to help bang out his plan. Maybe one of these days he’ll take some serious steps to keep PennHIP from going the way of the Betamax. I really wish he would. Our dogs deserve better.
OK, so PennHIP vs. OFA…what do you do?