Tests & diagnosis

Diagnosing fibromyalgia is difficult because there isn't a single, specific diagnostic laboratory test.  In fact, before receiving a diagnosis of fibromyalgia, you may go through several medical tests, such as blood tests and X-rays, only to have the results come back normal. 

Although these tests may rule out other conditions, such as rheumatoid arthritis, lupus and multiple sclerosis, they can't confirm fibromyalgia.

General classification guidelines for fibromyalgia, established in the 1990s by the American College of Rheumatology, are generally used in the assessment and study of the condition.  According to these guidelines, to be diagnosed with fibromyalgia you must have experienced widespread aching pain for at least three months. 

You will also have a minimum of 11 specific locations on your upper body and certain joints that are abnormally tender under relatively mild, firm pressure. Some physicians today will accept that tenderness in seven or eight of these points, alongside other symptoms presented,  is sufficient to warrant a diagnosis of fibromyalgia.

In addition to taking your medical history, a doctor checking for fibromyalgia will likely press firmly on specific points on your head, upper body and certain joints so that you can confirm which cause pain.

Not all doctors agree with these guidelines. Some believe that the criteria are too rigid and that you can have fibromyalgia even if you don't meet the required number of tender points. Others question how reliable and valid tender points are as a diagnostic tool.