Get the right medical diagnosis

Physical complaints can be hard to describe, especially when they are vague or come and go. Like a car that works perfectly as soon as you take it to the mechanic, symptoms often disappear when we're at the doctor's office. But when you can't explain your symptoms, you increase the chances of unnecessary tests, needless trial-and-error treatments, and even misdiagnosis.

I find it much tougher to get at the root of a problem when a patient tells me that she has "trouble walking and it hurts all over" than when she provides a clear description, such as, "I've had low-back pain and heaviness in my legs for the past six months that gets worse after I walk two blocks, then improves when I sit down."

Though it's sometimes difficult to express why, when, or even where you hurt, knowing what questions your doctor will ask—and thinking about how to answer them—can help you get a quick, accurate medical diagnosis. Here's how to prepare for your office visit.

Your doctor will ask for several pieces of information. To figure out how to answer, remember the letters O-P-Q-R-S-T and jot down the answers before your appointment.

O: Onset

When did the symptoms start, and what were you doing at the time? Was the onset gradual, sudden, or a worsening of a chronic complaint?

P: Place

Where does it hurt?

Q: Quality

What type of discomfort is it? Sharp, stabbing, dull, achy, cramping, pulling, squeezing, or something else?

R: Radiation

Does the pain radiate to another part of the body? The answer can be a tip-off for your doctor. For example, a sudden, crushing chest pain that moves to the jaw can be a red flag for a heart attack; pain in the upper abdomen (particularly on the right side) that travels to the back and right shoulder may signal gallbladder problems.

S: Severity

How severe is your pain on a scale of 1 to 10, with 0 being no pain; 5, moderate pain; and 10, the worst possible pain? Though the perception of pain varies a great deal from person to person, that scale is useful for assessing your own pain over time (e.g., it began at a 3, and two days later, it's a 9) and to describe how effective a treatment may be (the pain was a 5, but after you took acetaminophen, or Tylenol, it reced­ed to a 1).

T: Time and triggers

How long have you had the symptom? How often does it occur, what is its duration, and does its intensity fluctuate? Is it more common at a certain time of day? Does something bring it on or make it worse? Is it present at rest or only with movement? Is it affected by activities such as walking, eating, getting out of bed, or climbing stairs?

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Identifying triggers can be challenging, so I often ask patients with migraines to track their headaches in a journal, online, or in one of the mobile apps that are available for this purpose. That helps each of us see patterns that casual ob­servation might miss.

When the symptom diary includes detailed attention to diet, for example, patients may discover a clear link between their symptoms and eating specific foods—or even dining out, because many restaurants use monosodium glutamate (MSG), which adversely affects many people. Other patients discover a connection with weather, realizing that their migraines correspond to changes in barometric pressure. And many women find a correlation with their menstrual cycles that is so precise that we can actually treat them preventively on vulnerable days.

Diaries also help in tracking non-pain symptoms, including those related to allergies, asthma, heart failure, Parkinson's disease, psoriasis, and many other conditions. Because you are not depending solely on memory, your doctor gets a more accurate view.

In medicine, a picture truly is worth a thousand words. Photographs and videos record physical findings—intermittent rashes, tremors, or muscle twitches—and can document an infection after surgery. That visual evidence will speak to your doctor much more directly than even the most eloquent verbal description and will help you get the most accurate medical diagnosis.