Adoption of SI Units

Rodney E. Willard, MD
JAMA. 1979;242(7):618. doi:10.1001/jama.1979.03300070016014.
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To the Editor.—  Metrication in US medicine is still proceeding at a painfully slow pace (240:1618, 1978). Physicians appear reluctant to accept a change for several reasons.

  1. The numbers reflecting the usually encountered ranges in health and various diseases will have to be revised. Decision points established by years of clinical experience must be altered.

  2. Clear-cut advantages in improving patient care are not immediately apparent. An older generation accepted a change in electrolyte reporting units because they could use Gamble's approach to electrolyte balance more conveniently. We lack similar schemes for easily showing the interrelationships of other laboratory data.

  3. Side issues in implementing the International System of Units (SI) distract attention from the main thrust. Molar vs mass units, Celsius vs Kelvin temperature, IU vs Katal enzyme units, and mm Hg or torr vs pascal pressure controversies have stirred emotions and divided efforts.

Metrication using the officially


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