A paramount goal of this blog is to understand the evidence
as it applies to the epistemology of medical knowledge, hypothesis testing, and
overarching themes in the so-called evidence based medicine movement. Swedberg et al report the results of a large[Amgen funded] randomized controlled trial of darbepoetin [to normalize
hemoglobin values] in congestive heart failure (published online ahead of print
this weekend) which affords us the opportunity to explore these themes afresh
in the context of new and prior data.
The normalization heuristic, simply restated, is the
tendency for all healthcare providers including nurses, respiratory therapists,
nutritionists, physicians, and pharmacists among others, to believe intuitively
or explicitly that values and variables that can be measured should be
normalized if interventions to this avail are at their disposal. As an extension, modifiable variables should be measured so that they can be normalized. This general heuristic is deeply flawed, and
indeed practically useless as a guide for clinical care.