*! version 1.0.0 19feb2019

Title

bmi -- Body Mass Index

Syntax

Compute BMI using variables:

bmi
newvarname
,
ht(varname:heightvar)
wt(varname:weightvar)
[
metric
category(newvarname:newvarname)
]

Immediate form for computing BMI:

bmii
#ht #wt
,
[
metric
category
]

bmi

* ht(varname:heightvar) variable defining height (in either inches or in meters)

* wt(varname:weightvar) variable defining weight (in either pounds or in kilograms)

metric indicates that height and weight are in metric units (i.e. meters and kilograms, respectively); default is English standard units (inches and pounds)

category(newvarname:newvarname) generates a new variable containing BMI categories

* ht(heightvar) and wt(weightvar) are required.

bmii

metric indicates that height and weight are in metric units (i.e. meters and kilograms, respectively); default is English standard units (inches and pounds)

category displays the BMI category corresponding to the computed BMI

Description

bmi computes body mass index (BMI) values for adults, which is defined as weight in kilograms divided by the square of height in meters (kg/m^2). When the
metric option is not applied, bmi will convert the English standard measurements for height (inches) and weight (pounds) into their respective metric equivalents and
then compute BMI. Additionally, bmi can provide categories (classification) of BMI values according to the World Health Organization
(see: http://apps.who.int/bmi/index.jsp?introPage=intro_3.html).

bmii is the immediate form of bmi; see immed.

Options

metric indicates that height and weight are in metric units. More specifically, height must be in meters and weight must be in kilograms. The default is that
height is in inches and weight is in pounds.

category(newvarname) generates a new variable containing weight categories according to WHO classification criteria (see: http://apps.who.int/bmi/index.jsp?introPage=intro_3.html).

Examples

1) BMI using variables

load data

. use http://www.stata-press.com/data/r15/nhanes2.dta, clear

generate a variable converting height in centimeters to height in meters

. gen ht_m = height/100

compute BMI values from metric units in a new variable called BMI2 and generate a new variable for BMI categories

. bmi BMI2, wt(weight) ht(ht_m) metric cat(bmi_cat)

graph BMI categories using catplot (downloadable from SSC)

. catplot bmi_cat

generate variables in which height is converted from centimeters to inches and weight is converted from kilograms to pounds

. gen ht_in = height / 2.5400013716

. gen wt_lbs = weight * 2.20462

compute BMI values from standard units in a new variable called BMI3 and generate a new variable for BMI categories

. bmi BMI3, wt(wt_lbs) ht(ht_in) cat(BMI_CAT)

graph BMI categories as percent of total

. catplot BMI_CAT, percent

2) BMI using immediate form

compute BMI for an individual who is 68 inches tall and weighs 180 pounds. Display category

. bmii 68 200, cat

compute BMI for an individual who is 1.75 meters tall and weighs 62.50 kilograms. Display category

. bmii 1.75 62.50, cat metric

Stored results

bmii stores the following in r():

Scalars

r(bmi) computed BMI value

Citation of bmi

bmi is not an official Stata command. It is a free contribution
to the research community, like a paper. Please cite it as such:

Linden A. (2019). BMI: Stata module for computing body mass index.

Author

Ariel Linden

President, Linden Consulting Group, LLC

alinden@lindenconsulting.org

Also see

Online: catplot if installed, mibmi if installed