The Devine Formula of 1974 was established to promptly establish the ideal body weight when calculating dosages of medications such as theophylline, digoxin, and gentamicin among others. Just like the Broca Index, Devine formula uses height only and has become the most commonly applied method for both scholarly and medical purposes. It is worth noting that the Divine formula was not empirically based on population data, but on estimates.
The only measurement required in Devine formula is height. The best equipment to get the actual height is a stadiometer.
The recommended procedure
Using a stadiometer, get the correct height and then apply the Devine formula below to calculate the ideal body weight.
Men: Ideal Body Weight (kg) = 50 kg + 2.3 kg per inch over 5 feet.
Women: Ideal Body Weight (kg) = 45.5 kg + 2.3 kg per inch over 5 feet.
Note: 1 kilogram (kg) = 2.2 pounds (lb), 1 meter = 3.28084 feet
Example, a 6-foot tall man should have an ideal body weight of 77.6 kilograms while a 6-foot tall woman should have an ideal weight of 73.1 kilograms.
Devine formula target population
The main target population that this formula applies to are those people who are taller than five foot (60 inches) or taller.
Pros of Device Formula
- The ideal weight can be determined easily using height only.
- It is very easy and can be determined fast especially when dosages need immediate administration.
Cons of Devine Formula
- Because the formula was based on estimation, it is only suitable for a very small population.
- Using the formula, the ideal body weight suggests values that are way too low in women and unacceptably lower for shorter women.
- Just like the Broca Index, the Devine formula does not factor anything that can be used to compensate the present weight and age.
While the formula has become one of the most applied, critiques have faulted it because it could not be supported using data. Indeed, even later formulae derived from it appear technically flawed.
While the application of the formula was invaluable in the past especially in field conditions, things have changed today, and additional factors such as weight, age, environment, and other diverse aspects should be included.
Since it is the most applied method, it is important always to point to the user that the results are only based on estimates.
Bhumika, S., Kathrn, S. and Clarie, B. (2006). Comparison of Ideal Body Weight Equations and Published Height-Weight Tables With Body Mass Index Tables for Healthy Adults in the United States. Nutritional Diabetics 1(3)312-319 Available at http://ncp.sagepub.com/content/21/3/312.abstract
Green B, Duffull S. (2002). Caution when lean body weight is used as a size descriptor for obese subjects. Clin Pharmacol Ther. 72:743–4.
Kirkpatrick, C., Duffull, B., and Begg, J. (1999). Pharmacokinetics of gentamicin in 957 patients with varying renal function dosed once daily. Available at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2014263/