Dr. Ferris correctly points out that physicians are humans and that "like all humans, often prefer to think dichotomously about phenomena that are clearly continua." He also correctly points that many classifications require arbitrary distinctions. They do not, however, require artificial and arbitrary dichotomies. In the example of myocardial infarction, an understanding of the impact of that infarction on subsequent cardiac function and subsequent risk is better obtained by assessing the electrocardiogram, enzyme results, imaging results, and clinical presentation as continua rather than a simplistic "Q-wave/no Q-wave" system. Even, as Dr. Ferris suggests, a different dichotomy based on R-wave change would not be a suitable substitute.

Dr. Spodik, a distinguished teacher, scholar, and cardiologist, published an article intended to end dichotomous thinking. As he points out, however, the result, as perverted by others, was simply to translate the dichotomy to Q-wave and non-Q-wave infarction. Dr. Spodik goes on to point out that the loss of R-wave voltage is not specific for infarction. This is true, but the post-test probability of this reflecting infarction is substantially increased when viewed in the context of evolving ST-T wave abnormalities.

I am pleased that both respondents share the view that dichotomies deserve understanding.