Elsewhere in today's New York Times today--a very nice of example of how Occam's Razor isn't always sharp, in Lisa Sanders' medical mystery column.
When making a diagnosis, doctors frequently cite the principle of Occam’s razor: the simplest answer is most likely to be the right answer, and a single diagnosis is more likely than a collection of diagnoses. This principle, however, doesn’t necessarily hold with older patients. High blood pressure is seen in 80 percent of those over age 70. Nearly half over 60 are overweight. A quarter are depressed. One in six Americans over age 40 will have cataracts in one or both eyes. Given these numbers, having a 76-year-old patient with all of these distinct diseases — as was the case with this patient — is common, and a doctor might not feel the need to look for a single, unifying disease process.She goes on to say about the patient in question--
As one of her daughters wrote in an e-mail to friends: “We were told that her psychological state, her neurological problem, her circulation issues and her excessive bleeding were an unrelated bunch of unfortunate circumstances conspiring to make this woman ill. It happens when you are old, we were told more than once.” This thinking was familiar to many readers. Jonquil of Utopia wrote: “ ‘It happens when you are old’ is such a dangerous diagnosis, yet it’s given every day. . . . G.P.’s need to be better trained in geriatrics.”Occam's razor isn't an all purpose good principle, but only good in certain cases.
Readers know that this column often reads like a detective story in which a single criminal (one disease) is responsible for a variety of crimes (symptoms). As a result, the reader has an advantage over a doctor, who has to figure out which patient, out of all those she has seen that day, has many individual problems without a unifying cause, and which will need Occam’s razor. While that distinction may not be sufficient, it is the necessary start of diagnosis.***
Happy Mother's Day!