Merritt Clifton -- when the numbers just don't add up

Reporters looking to write articles about 'pit bulls' often find themselves looking to report "both sides" of the story.  Essentially, every expert organization in the country agrees that there is nothing inherently dangerous about 'pit bull type" dogs and that breed specific laws aren't the solution -- which leaves only a couple of independent sources to refer to when trying to find the 'pit bulls are dangerous" side of the equation.

One of those sources is Merritt Clifton. I've written about Clifton before, and his tendency to misuse data to support his personal agenda (or, possibly, because having the lone dissenting point of view is possibly the only way he has any relevancy at all to the conversation). Others have written about the inaccuracies of his data too --- and I'll mention those later.

While an initial look at Clifton's methodology shows some glaring flaws, the deeper you look at the numbers, the more glaring those flaws become.

In December 2009 the Clifton Report featured 2,694 "attacks doing bodily harm" and 1,493 "Maimings) in the 27 year stretch from 1982 to 2009.   There were several "interesting" things about these numbers:

1)  Clifton issued a 2006 report that suggested there were 2,209 "attacks doing bodily harm" and 1,323 "maimings".  A little math then shows that from 2006-2009, there were 485 'attacks doing bodily harm" and 170 "maimings" -- however, during the same timeframe, showed that the total numbers attributed to 'pit bulls, rottweilers and presa canarios" went up by 509 and 215 respectively - or more than the grand total of all dogs combined. This is, of course, mathematically impossible.

2) While HCUP estimates show that there have been an average of about 7800 hospitalizations (requiring an overnight stay) in the past 16 years, Clifton's study only included less than 100 per year -- or about 1% of the total hospitalizations -- and because he relies primarily on media reports for his information (and not, say, hospital reports), his numbers are statistically not representative.  Now, Clifton will say that his study isn't meant to be all inclusive, but only cover the "worst of the worst", he is basing which incidents to include off of media report information. It seems like it would be impossible to decide which incidents to include, and which ones to not include, based on media reports on the injuries, and impossible to assume that every, or even most, major attacks are covered by the media.

But let's assume for a minute that Clifton's report is somehow, miraculously, still valid.  We still have some issues to clear up on this 2011 report.

So, I got a copy of the 2011 report directly from Clifton - -this is an updated version of the report from one published a couple of months ago that had a glaring mathematical 'gremlin' in it that even I felt guilty about beating him up over the numbers. So I pointed out that a couple of numbers were clearly wrong, and he went back and redid his math to come up with more 'accurate' numbers.  Which are still, well, odd.

Below are the numbers -- the first number is based on the December 2009 report linked to above, the second number is for the August 2011 report I received from Clifton himself. The third number is my calculation of the difference between the 2 numbers that would reflect the actual number of incidents in each category for the 19 months of 2010 and through the first week of August, 2011.

                                                                2009            2011        19 month total

Attacks causing bodily harm     2694              3383             689

Deaths                                                345                  451            106

Maimings                                         1493               1917            424

So does anything stand out to you about these numbers? 

Does it seem odd to anyone else that a full 20% of the "attacks causing bodily harm" over the past 29 years have happened in the past 19 months?  To put this in perspective, for the first 27 years of this report, Clifton reported an average of just under 100 of these "worst case attacks" each year -- but in the past 19 months it averages out to be about 450 per year -- a 450% increase.

Clifton is now reporting that 22% of all "maimings" over the past 29 years have occurred in just the past 19 months, and 24% of all fatalities.  There is just absolutely no data, anywhere, that reflects anything near this type of increase. The HCUP numbers listed above have shown a gradual 89% increase over the past 15 years -- but nothing close to the 450% that Clifton is showing, and nothing that would show a sudden increase like these number project.

There could be any number of reasons for this -- here are a couple that come to mind:

1) There is no valid statistical way to gather the information Clifton seems to be trying to gather.

2) There is much better access to information via the internet now than there has been historically -- which means that all of Clifton's historical data is majorily incomplete (which we've all known for years).

There are several other questionable numbers that don't add up in the 2011 report. He's showing an increase in 'attacks causing bodily harm" among "pit bulls, rottweilers, presa canarios, Dogo Argentinos, Fila Brasiliero and Cane Corsos" had an increase of 446 incidents over the past 19 months.  He's added more breeds to this category, but if you back out the 16 incidents of the added breeds, you have 430 incidents that have increased in this category.  However, the total number for "pit bulls, rottweilers and wolf Hybrids" went up by 614 -- which would lead to one to believe that there were around 170 incidents involving Wolf Hybrids over the past 19 months, but Clifton only has 81 total by these types of dogs over the past 29 years.

Then, there is the notes section. I got clarification from Clifton that the cases in the Notes section are included in the actual numbers.  So among the incidents that Clifton uses to mention how vicious 'pit bulls are' include:

1) A woman whose horse was startled by a pit bull and the horse kicked the woman

2) a girl who ran from a dog that never bit her and ran in front of a school bus and was hit by a bus (the girl likely ran from the dog because of the same hysteria that Clifton has helped create)

3) An attack incident involving 12 mixed breed dogs and 1 'pit bull' -- this shows up in Clifton's numbers as only a 'pit bull' attack because Clifton does not count mixed breed dogs in his reports.

4) An animal control officer who died from head injuries she suffered when she fell while trying to catch a dog.

5) A police officer who died from blood infection he received as part of a dog bite

6) And several incidents where the victims died from heart attacks

7) A person who was hit by a train when the dog they were walking took off after its owner (who was on a bicycle) and pulled the dog walker in front of an oncoming train.

8) A case where a dog's breed ID was labeled as an Akita, Weimaraner, Pit Bull and various combinations of mixes of these breeds -- but Clifton includes this case as a 'pit bull' even though he specifically notes that cases in which the breed of dog is uncertain are not included in the report.

All (and who knows what else) are bizarrely added to Clifton's report -- along with a host of other non-bite related deaths and injuries. This, I guess is fine, except he then used the data to support that certain types of dogs are more aggressive than other types of dogs based on a collection of data that includes non-bite-related incidents.

Clifton has also has apparently heard other peoples' criticisms that his data does not take into account breed population numbers -- and this time has decided to use, catch this, online classified advertisements for puppy sales, as a method to determine populations of various breeds. While I acknowledge that there is no good way to determine the number of dogs per breed, I am more than willing to acknowledge that online classified ads is a ridiculous method of trying to get that information.

Clifton has for years used his report to drive hysteria about 'pit bull' type dogs, however, every bit of actual research and science disagrees with his report.

Actual scientific studies indicate that there are few differences in aggression between different breeds of canines.  The Science of DNA testing has also proven that visual identification of dogs (which all breed ID was solely done by until the past couple of years) is an unreliable way to identify a dog's heritage.  Clifton acknowledges in his 'analysis" that breed specific legislation is very difficult to enforce because for 'pit bulls' there is no breed standard -- and yet, doesn't acknowledge that his data is completely skewed by this same complete inability to identify types of dogs.

But Clifton carries on - ignoring science and ignoring the faulty numbers in his own reporting. And yet, because he is nearly the lone voice for the 'pit bulls are mean" crowd, the press eats it up. 

A lot of others have written a lot about Clifton's "report" over the past few years, most focused on his failed information gathering methods and other innaccuracies in the report (particularly in the Analysis section) and here are a few of my favorites:

No Pit Bull Bans -- which has a great part about his analysis about 'pit bulls' and his failed logic on that front.

Lassie Get Help -- has a great report that walks through the failures of the numbers -- but at a one-time glance at the 2006 report.  They just continue to look worse over time. She then takes on the inaccuracies in the analysis section in her part 2 -- including the false idea that German Shepherds are herding breeds.  There is also the strangeness that Clifton apparently thinks Bull Mastiffs and Presa Canarios are the same breed.

One other thing about Clifton's "analysis", Clifton uses insurance issues to justify the need for breed-specific legislation. Clifton seems completely unaware that several national insurance companies have no breed restrictions or premiums, and many of the ones that do have done so because a handful of people like Clifton have created an unfounded hysteria around certain types of dogs. 

Clifton then goes on to compare 'pit bulls' to "pumas" (yes, pumas) even though the dogs are clearly domesticated and Pumas are not....but hey, if you're numbers aren't going to really make sense, then why should the analysis of those numbers?

So this is Merritt Clifton. Possibly the leading voice in the "Breed Specific Laws are a good thing" movement - and these are his numbers. Filled with numbers that don't add up, an under-represented sample size, breed identification issues, reports of aggressive incidents that weren't, data periods in which more pit bull attacks are counted than total dog attacks, 19 months worth of data accounting for 20-25% of the report, random analysis statements and comparisons between dogs and pumas.

THIS is the leading voice of the anti-pit bull movement.  The people who oppose such legislation include professional dog training organizations, professional veterinary organizations, the national animal control association, animal welfare groups and real scientists.

Sometimes there is only one real side to an argument. This is one of those cases.

Comments

[Karen]

Excellent article Brent. Thank you. We've linked to it on our facebook page (American Pit Bull Terrier Association Inc NZ) in the hope some of our media representatives will read it! Now you need to sort out Colleen Lynn!

[Brent]

Thanks Karen. Here's the breakdown on Colleen:

http://btoellner.typepad.com/kcdogblog/2010/03/the-truth-behind-dogsbiteorg.html

[Jennifer Brighton]

And Karen, you might find this little gem a worthwhile read about Colleen Lynn from Pit Bulletin Legal News. I believe he references Brent's blog, as well.

http://pitbulletinlegalnews.com/pro-bsl-experts/dogbiteorg/109-collen-lynn-seattle-animal-control-records

[Mike]

"Sometimes there is only one real side to an argument. This is one of those cases."

I love your blog. This might be my new favorite anti-bsl quote!

[Jennifer Brighton]

Brent, I haven't had time to read your blog carefully, but will do. However, aren't Cliffton's numbers skewed just by the fact they are so out of line with what the CDC reports as far as # of dog bites per year?

From the CDC website (and I've also seen this reported in medical journal blogs):

"About 4.5 million people are bitten by dogs each year. Of one in five of those who are bitten, a total of 885,000 require medical attention for dog bite-related injuries.

In 2006, more than 31,000 people underwent reconstructive surgery as a result of being bitten by dogs."

If 31,000 in 2006 underwent reconstructive surgery for dog bites, and assuming 2006 wasn't much different than other years as far as attacks, wouldn't the rate of hospitalizations be much higher than what Cliffton reports? How can he even hold himself out as providing accurate information with this type of discrepancy? I guess I'm not clear if his numbers you cite are supposedly the result of only pit bull attacks, but even so, what about those other 885,000 dogs that have bitten, requiring that the person seek medical attention, 31,000 of which required surgery?

I don't know how anyone can take him seriously. I'm no mathematician (just ask my husband), and maybe I'm just plain dumb, but his statistics make no logical sense to me. I guess that's what you are getting at.

Thanks for your hard work in sifting through all this.

[Brent]

Yes Jennifer -- I get to that but I used the HCUP report instead of the CDC -- but yes, regardless of which of these reports you use, Clifton's "study" covers less than 1% of the total reports requiring an overnight stay in the hospital. Clifton counters this by saying he only covers the "worst of the worst", but his qualification of this isn't based on hospital data, it's based on media reports...and even then, he seems pretty arbitrary in his inclusions because how could someone being hit by a car while fleeing a dog that never bit them fall under "the worst of the worst" dog attacks? This of course is all in addition to the new reality that 20% of all all the incidents he's covered have now allegedly happened in the past 19 months. There is no way anyone with any discernment at all could take these numbers seriously.

[EmilyS]

are you away of the trend, prominently instituted by Animal Farm Foundation (which now owns NCRC) to accept the appellation of any dog as a "pit bull" if the media, animal control or anyone else calls it a "pit bull"? Don Cleary of NCRC repeatedly asserted "there is no such breed as a "pit bull" in his recent presentation, and indeed the new NCRC publication promotes the same point of view, using DNA evidence of "breeds" Their position, to the extent I can understand it, is that "you can't tell what breed an unregistered dog is"; "pit bulls are more discriminated against than any other dog" and "we can fight bdl by encompassing ALL the dogs as a pit bull so insurance companies will lose business if they discriminate"

Im not sure they're aware of how much this stance plays into the hands of the Cliftons and Lynns of the world, because AFF cannot dispute the notion that it's inaccurate or unfair to attribute bites to "pit bulls" when the dog is a mastiff, Cane Corso or something else.

(BTW, that 4.5 million dogbite statistics that CDC is using is in itself highly suspect)

[Brent]

Emily,

I spent a lot of time talking to AAF people last month, and I'm not sure your interpretation of their stance is completely accurate (could be, but certainly not my impression from talking to several of their members). They still actively speak about Victoria Voith's research, and have more research on the way about faulty breed ID. It's still very much highlighted on their webpage:

http://nationalcanineresearchcouncil.com/resources/breed-identification/

You could be right, but this is certainly not indicative of any exposure I've had with them.

[Dianne R.]

Although there is no breed called "pit bull" the breed "American Pit Bull Terrier" does have breed standards under UKC and ADBA

http://www.apbtconformation.com/standardcomparison.htm

Just because the AKC due to its elitist nature does not recognize APBT does not mean it is not a breed. I'm old enough to remember when "border collie" was not an accepted AKC breed. The CFC does not recognize Bengal cats as a breed, yet they are the most popular pure breed in the US. So I wish people would familiarize themselves with the standard, so when the media says "an 120 pound pit bull" you can call them on it. Breed standard is 30 to 60 lbs.

[Brent]

Dianne -- I, for one, won't be in the conversation of "there is no such thing as a 'pit bull'". However, the problem is that so much of what is being called a 'pit bull' is nowhere near any type of breed standard. There is far too much of the "a pit bull is what we say it is" type of mentality out there (which is, I think, what Emily is referring to) -- when the majority of these dogs are simply mixed-breed dogs and should be labeled as such.

But yes, earlier this week I had a commenter saying that a Presa Canario was a "pit bull" type dog. When you start broadening a category that much, you end up with anything with short hair that weighs between 30 and 130 lbs being labeled a 'pit bull' -- which is exactly what Lynn, Clifton, Skeldon and the media have essentially done. With that type of criteria, no wonder they would be high in bite numbers.

[Pit Bull=APBT]

"When you start broadening a category that much, you end up with anything with short hair that weighs between 30 and 130 lbs being labeled a 'pit bull' -- which is exactly what Lynn, Clifton, Skeldon and the media have essentially done. With that type of criteria, no wonder they would be high in bite numbers."

And groups like Animal Farm Foundation are legitimizing this by going along with the whole "There is no such breed as a Pit Bull" and "A Pit Bull is whatever dog someone has labeled a Pit Bull" BS. They are not helping the cause, they are helping the enemy.

[Pit Bull=APBT]

Diane, The AKC recognizes the American Staffordshire Terrier, a breed so close to the APBT that many dogs are dual registered as APBTs in the UKC and ASTs in the AKC.

[MaryH]

Doesn't anyone find the Voith study suspect due to the fact that the dogs tested were of unknown ancestry and there is no way to prove that the DNA test results were actually indicative of the genetic breed makeup of the dogs? Unless I missed something.....

BTW, I recently read a statement written by a person in the field of genetics, specifically working with dogs, and she claimed the breed tests were complete nonsense.

And maybe I am completely misinterpreting AFF's stance, but as far as I can tell, they are actively embracing the notion of "it's a pit bull if someone says it is and that's all that matters". One of their reps recently stated on FB that the goal was to get as many dogs as possible regardless of breed under the umbrella term of "pit bull". FWIW

Who knows what all this will mean for the Pit Bull in the long term, but now more than ever, bite stats that assign bites to breeds are IMO utterly useless.

[Brent]

I've got all kinds of mixed reviews on DNA tests -- but I know that they have made a lot of improvements to the genetic markers over the past several years and I think they are a lot more accurate than they used to be. That said, regardless, I find it ridiculous that someone thinks they can identify the ancestory of a mixed breed dog based on what it looks like when DNA struggles to tell the difference. The biggest problem with the Voith study is, IMO, the small sample size...but my experience tells me that if you did 10x the sample size you'd end up with a similar result.

[MaryH]

My point re: the Voith study is this: there was no way to prove one way or the other if those DNA results were accurate because the dogs had UNKNOWN HISTORIES. If a bunch of shelter workers were asked to ID a bunch of mixed and purebred dogs of KNOWN history, then that study would have meant something to me.

I've not seen anything to lead me to believe that DNA tests are anything other than a waste of money.

Right now, all these dogs (even purebred, registered dogs of known ancestry) are coming up all kinds of wacky mixes not even close to what the dog looks like or is known to be. On Facebook the other day, there was a 67 lbs Pit Bull mix-looking dog that was supposedly 75% Bichon according to his DNA results. This dog was brindle, btw, and none of the breeds that came up in the DNA results were breeds that could genetically come in brindle AFAIK - it's my understanding that brindle is dominant and it's not going to just randomly pop up in breeds that do not come in brindle (if I'm wrong, someone please feel free to correct me!)

I just ignore DNA tests and never use them in any argument against BSL. And I can't help thinking, "Jeez, what if one day they actually ARE accurate, and the tables get turned and they are used to target and destroy certain breeds....?"

Sorry, I know this blog wasn't about DNA testing, kinda went off on a tangent.

[Brent]

Mary -- what test did they use on the one on Facebook?

Most of the tests are complete crap...I do think the Mars Wisdom Panel test has a depth of breeds that others don't have, and better genetic markers, based on my experience with the various tests.

I used to be scared of DNA testing for exactly the reason you mention above...but now, more than ever, I think truth and honestly will come out in our favor every time.

[MaryH]

I'm not sure what test they used, Brent, but yes, it is my understanding that the Wisdom test is the best relatively speaking on the market. (They have tests that can supposedly ID purebred dogs, now. Used to just be mixed breeds.)

And I 100% agree with you that truth and honesty is the way to go, no matter what.

[EmilyS]

for 100 years, "pit bull" has meant only "American pit bull terrier".

Deciding now that the term should be used for any dog with a bighead, fat chest and short hair is just a bad bad tactic.

Call it a "mixed breed" unless you have good reason to believe it's an APBT (based on appearance and behavior). Indeed, most shelter/rescue dogs are mixed breed dogs, whatever their superficial appearance (even some of the vaunted Vick dogs are clearly not purebred APBTs if you know anything)

Then insist to the Cliftons/Lynns and all the other deceivers and haters that the dogs they are collecting statistics on are MIXED breed dogs (with some few exceptions).

It's weird to see NCRC promoting "no such thing as a pit bull" (Don Cleary proclaims this in their webinar) ... at the same time their parent organization is promoting "everything is a pit bull". I believe they think that if all dogs are pit bulls, there can't be discrimination in things like insurance because companies would lose all that business. Not the way life works, at all.

To call everything a pit bull absolutely plays into the hands of those who want to make "pit bulls" the villain... because OH LOOK! all these nasty biting dogs are "pit bulls".

As for the DNA tests, I'm just extremely skeptical. Few dog "breeds" are older than 100 years and they all derive from a few types (and ultimately of course from ONE species); how does DNA get to be distinguishable in that time? A dog is a "breed" based on physical characteristics and temperament according to a standard. What I'd love is to see DNA comparisons of extremely similar, but separate breeds: rough/smooth collie - border collie- English shepherd - Sheltie - Australian shepherd. English setters-Irish setters. Or bull terrier- APBT-AST-SBT . If this were about science, someone would be doing those kinds of comparisons.

[Brent]

Emily -- without the DNA differences, there would be no difference in appearance among breeds. Dogs with identical DNA will be very similar in appearance (although behavior/temperament will vary). So if these DNA differences exist to adjust appearances, then they should, in theory, exist as markers to distinguish the breeds.

I am curious on certain things like comparisons between similar breeds, and how related breeds show those distinctions. I think Mars is more concerned about marketing this to raise money while the breed clubs (who I would think would have an interest in this) seem more concerned about saying DNA testing is bunk than actually doing their own testing.

I agree with your stance on the 'pit bulls' vs "american pit bull terriers' and that it does not benefit us to call everything a 'pit bull'. And you may very well be right about AFF having this stance....but I certainly haven't seen this be a focus from them...

[Pit Bull=APBT]

This is directly copied and pasted from AFF's Facebook page:
""Pit bull" is not a breed or breed mix, but an ever expanding group that includes whatever an animal control officer, shelter worker, dog trainer, politician, dog owner, police officer or newspaper says it is."

AFF is most definitely of the opinion that a Pit Bull is whatever someone calls a Pit Bull.

[EmilyS]

re DNA: I dunno Brent.. I'd like to see the actual science, explained by someone who doesn't have a financial interest in this. Sure there are genetic markers for appearances.. which is why Dawn's purebred AST tested as a border collie/boston terrier (they are all black/white) Considering that all mammals share about 96% of genetic material, chimps and humans share about 99% and dogs descend directly from wolves and are even more closely related genetically (related example: it took some very close, and somewhat controversial, testing to determine that the "red wolf" is probably a wolf-coyote hybrid)... I retain my skepticism.

[myra]

Great post exposing Clifton garbage numbers.

[KDelise]

I can't believe some of these comments, assumptions and accusations.

AFF and NCRC's mission and goal has always been to help dogs, especially those in the most dire need of help, that being dogs that are labeled "pit bulls."

Our stance is clear: We should never assume we know more than we do, especially when it comes to breed.

When we know a dog is an "American Pit bull Terrier," or an American Staffordshire Terrier" we have no problem calling it that.

"Breed" by it's very definition means a closed and defined group. And the term "pit bull" today does NOT refer to a closed group - it is used to define all dogs that someone thinks is a "pit bull" - regardless of its genetics.

If you bothered to look at NCRC's 2010 Investigative Report we clearly show how we label dogs: Was there any pedigree on the dog? Did the owner have papers or purchase the dog from a breeder? Does our expert advisor think the dog is a purebreed dog?

Bottom line: If there is reliable evidence that a dog is a particular breed we have no problem calling it that, but we are not going to label a dog a "pit bull," or any breed for that matter- unless we know that to be a fact.

[KDelise]

This is directly copied and pasted from AFF's Facebook page:
""Pit bull" is not a breed or breed mix, but an ever expanding group that includes whatever an animal control officer, shelter worker, dog trainer, politician, dog owner, police officer or newspaper says it is."

AFF is most definitely of the opinion that a Pit Bull is whatever someone calls a Pit Bull.

No. You have totally misunderstood this. We are saying that the recent and common practice of calling all types of dogs, regardless of their true pedigree or genetics, a "pit bull" is exactly why "pit bull" is not a breed.

[Brent]

PB+APBT -- while Karen addressed this, I think there's a huge difference between making a statement that is, undoubtely, how breed specific legislation is enforced in this country, and actualy endorsing that practice.