Zebras, hoof-beats and Dr. House: Differential Diagnosis

Differential Diagnosis: WHAT is it?

and WHY do I care?

by Madelyn Griffith-Haynie,
#1 of a 2-parter in the Comorbities Series

(To find out how the Zebras relate, read the article!!) 

differential diagnosis is one which examines all of the possible reasons for a set of symptoms in order to arrive at an identification of the cause (or combination of causes) of a presenting problem.

It’s a fairly simple process of elimination that can become unblievably complex in an eye-blink, “simply” because so many diseases and disorders present with similar symptoms,

Although the term “differential diagnosis” initially referred to issues of physical health, today many doctors in the mental health field also use this system of diagnosis.

Diagnosticians specialize in differential diagnosis.

Everybody’s favorite Diagnostician

And who would that be?

Why, House, of course!

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House — the Cliff Notes:

In the popular TV show, House, a diverse team of unusually attractive doctors works under a brilliant but cantankerous head of neurosurgery in a metropolitan hospital.

Each week the team examines various symptoms and clues, looking for underlying causes that might help them figure out what is wrong and what they must do to restore the health of this week’s patient.

  • This week’s patient lands in their care through a variety of unexpected means – always suddenly urgent. Both patient and problem are introduced to us at the very top of every show.
  • The team immediately convenes in a sort of hospital “situation room” to play a fast round of “WHAT could possibly account for these bizarre symptoms?” as House writes each possibility on a whiteboard, crossing things out as the team argues for and against theory after theory.  An initial diagnosis is agreed upon, and treatment begins urgently.
  • The patient’s condition is monitored throughout the process, of course, and when he or she fails to improve – or when the condition worsens – House and team go back to the drawing board. Treatment failure becomes another clue in the process of putting the pieces together in a way that solves the puzzle.  Just like in life – with a few little differences.

Even for a crackerjack team like House, et. al, it is not uncommon to be misled, going back to the drawing board several times (literally, during each episode of this particular TV series), before a treatment protocol can be suggested with any confidence that it might be expected to work this time.

“When you hear hoof-beats, look for horses, not zebras.”

Most real-world doctors are familiar with the above quote from their medical training.  It is often cited to impress upon young med students one of the cardinal rules of “real life” differentials:

Always begin by considering the most common diagnosis first.

Don’t move on to the more exotic possibilities until the simplest diagnoses have been ruled out — for legitimate, well-thought-out reasons.

Except on House, of course!

Since the producers and sponsors of House are more concerned with delivering an hour of dramatic television than providing an accurate example of the differential diagnostic process, the show’s writers ignore that particular “simplest first” caveat.

As the audience, we love to play right along. We just know that whatever is wrong with the patient with the toothache is definitely more likely to be a brain tumor than a cavity.

House “regulars” know that each episode follows a pattern: 

  1. The team will rule out the obvious in the first fifteen minutes, brow-beaten by a scowling, scornful, addicted-to-pain-pills-but-too-brilliant-to-fire Dr. House;
  2. One of the team will suggest something like neuropathy right before or after the first commercial;
  3. Shortly before the halfway point, when the patient’s symptoms don’t quite fit the parameters of a neurological diagnosis, House’s shrink colleague and buddy will be called in to check out psychiatric issues;
  4. When (just before we break for another commercial) the patient almost dies, a junior member of the team will campaign for treating the patient for something cryptic – like atypical meningitis –  and
  5. When a FATAL treatment mistake is just about to be made . . .
  6. ANOTHER member of the team will save the day by determining that some kind of genetic mutation has been activated by exposure to an esoteric strain of bird-flu because
  7. SOMEONE else from the team was sent to investigate the home of the patient (now lingering on his deathbed) to discover that the basement is full of pigeon poop!

Yep, that’s a differential diagnosis in a nutshell!
(minus the drama, the commercials, and the pigeon poop)

“real life” differential follows the House pattern:

  1. It starts by reviewing the patient’s case: beginning with the presenting problem.
  2. Along with examining the patient, the clinician will probably  interview all concerned  as s/he  catalogues all the symptoms, which generally leads to
  3. Compiling a patient history – which provides a picture of the patient’s background, family of origin, personal quirks, hobbies and habits, social interactions and practices;
  4. Certain tests are sometimes ordered as part of the drill, to obtain specific information about the patient’s current condition;
  5. Additional interviews with friends and coworkers might be compiled in a particularly puzzling or complicated case, or when the patient isn’t able to provide adequate information for any reason;
  6. Other specialists are sometimes called in, to draw upon a wider body of knowledge and experience; and
  7. It sometimes becomes necessary to examine the patient’s environment to look for causes that nobody thought important enough to mention in this particular context.

WHY Differential diagnosis?

The most obvious answer – to make sure you’re not being treated for something that’s not the problem – is only the beginning.

IN ADDITION to identifying the source accurately, a first-rate differential diagnosis
will allow you, the patient, to:

  • work with your treatment team more effectively, since everyone is clear about which condition (or combination of conditions) they are working ON;
  • understand the source of your symptoms, as well as an appropriate list of  interventions available to make you more comfortable and effective;
  • make decisions about your future based on a realistic assessment of the progression likely with your diagnosis;
  • eliminate more frightening possibilities so you can stop worrying about them;
  • develop an effective treatment plan;
  • enable you and your loved ones to plan around your condition while you are working on strategies designed to clear up the worst of the problems.

So what does all this have to do with ADD, and why should we care?

Ah, hang onto your hats – for those of us with executive functioning deficits, here’s where it begins to get dicey!  [CLICK HERE  for Part II]

IN ANY CASE, stay tuned. There’s a lot to know, and a lot more to come.

As always, if you want notification of new articles in the Basics Series – or any new posts on this blog – give your email address to the nice form on the top of the skinny column to the right. (You only have to do this once, so if you’ve already asked for notification about a prior series, you’re covered for this one too). STRICT No Spam Policy

If you’d like some one-on-one (couples or group) coaching help with anything that came up while you were reading this article (either for your own life, that of a loved one, or as coaching skills development), scroll down to click the Brain-based Coaching Link below, with a contact form at the bottom, or click the E-me link <—here (or on the menubar at the top of every page). I’ll get back to you ASAP (accent on the “P”ossible!)

Related articles right here on ADDandSoMuchMore.com

Working with your Doctor

Related articles ’round the ‘net

BY THE WAY: I revisit all my content periodically to update links — when you link back, like, follow or comment, you STAY on the page. When you do not, you run a high risk of getting replaced by a site with a more generous come-from.

About Madelyn Griffith-Haynie, MCC, SCAC
Award-winning ADD Coach Training Field founder; ADD Coaching field co-founder; [life] Coaching pioneer -- Neurodiversity Advocate, Coach, Mentor & Poster Girl -- Multi-Certified -- 25 years working with EFD [Executive Functioning disorders] and struggles in hundreds of people from all walks of life. I developed and delivered the world's first ADD-specific coach training curriculum: multi-year, brain-based, and ICF Certification tracked. In addition to my expertise in ADD/EF Systems Development Coaching, I am known for training and mentoring globally well-informed ADD Coach LEADERS with the vision to innovate, many of the most visible, knowledgeable and successful ADD Coaches in the field today (several of whom now deliver highly visible ADD coach trainings themselves). For almost a decade, I personally sponsored and facilitated seven monthly, virtual and global, no-charge support and information groups The ADD Hours™ - including The ADD Expert Speakers Series, hosting well-known ADD Professionals who were generous with their information and expertise, joining me in my belief that "It takes a village to educate a world." I am committed to being a thorn in the side of ADD-ignorance in service of changing the way neurodiversity is thought about and treated - seeing "a world that works for everyone" in my lifetime. Get in touch when you're ready to have a life that works BECAUSE of who you are, building on strengths to step off that frustrating treadmill "when 'wanting to' just doesn't get it DONE!"

14 Responses to Zebras, hoof-beats and Dr. House: Differential Diagnosis

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    • Thanks, Angelena. You probably know this already, given the nature of your site, but “creatives” include a statistically significant percentage of ADDers. A great use for collage is mind-mapping goals in pictures rather than words (frequently better for Visual processors). If you have any content related to that process, I’d love to feature you as a Guest Blogger (with a link back to your bio and your site.) Let me know.

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      I keep looking for a place to post a comment on your site – no luck so far. Want you to know that I’ve linked you to “ABOUT Alphabet Disorders” here – because PAIN affects cognition!

      Loved the video of the doctor’s wife’s “miracle” btw. Thanks for taking the time to comment so I’d know about you.


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    • Hi there – Akismit marked you as spam, but it sure looks like you’ve got a legit site going (even though I can’t read a word of it!) ::grin::

      RE: using my stuff: I’m assuming you’d have to translate, yes? As long as you include “from Madelyn Griffith-Haynie by permission” and link back to the original post (maybe with a “Read it in English HERE”), I’d be thrilled to think those who prefer to read in a language other than English (as well as those who don’t speak English) would have access to what I’ve learned in the last 20 years. Help yourself – let me know and I’ll post a link to your site saying Read it in [Polish?] – so sorry – we don’t teach languages well in the US, so I’m ignorant about just about anything besides English or Spanish. And thanks for asking!


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    • THANKS – and thank you for taking the time to let me know a nice quiet color scheme works for you. I’m working hard to implement ADD-friendly design concepts (despite the fact that WordPress seems not to like it , so it is HIGHLY labor-intensive to do so!! :-))

      I’m new to this format, so forgive me for stripping your link code. Akismet marked you as spam, and until I know what I am doing, I’m not allowing “live” links in those cases. I left enough so that someone could get to you if they were really eager to do so. (Hopefully, I’ll get the hang of this soon!)


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