bmi_fun_cat {cchsflow}

Categorical BMI (international standard)

Description

This function creates a categorical derived variable (HWTGBMI_der_cat4) that categorizes derived BMI (HWTGBMI_der).

Usage

bmi_fun_cat(HWTGBMI_der)

Arguments

HWTGBMI_der

derived variable that calculates numeric value for BMI. See bmi_fun for documentation on how variable was derived.

Details

The categories were based on international standards and are divided into four categories: underweight for BMI < 18.5 (1), normal weight for BMI between 18.5 to 25 (2), overweight for BMI between 25 to 30 (3), and obese for BMI over 30 (4).

HWTGBMI_der_cat4 uses the derived variable HWTGBMI_der. HWTGBMI_der uses height and weight that have been transformed by cchsflow. In order to categorize BMI across CCHS cycles, height and weight variables must be transformed and harmonized.

Value

value for BMI categories in the HWTGBMI_der_cat4 variable.

Examples

 
# Using bmi_fun_cat() to categorize BMI across CCHS cycles
# bmi_fun_cat() is specified in variable_details.csv along with the 
# CCHS variables and cycles included.

# To transform HWTGBMI_der_cat4 across all cycles, use rec_with_table() for 
# each CCHS cycle.
# Since HWTGBMI_der is also a derived variable, you will have to specify 
# the variables that are derived from it.

library(cchsflow)

bmi_cat_2009_2010 <- rec_with_table(
  cchs2009_2010_p, c(
    "HWTGHTM",
    "HWTGWTK",
    "HWTGBMI_der",
    "HWTGBMI_der_cat4"
  )
)

head(bmi_cat_2009_2010)

bmi_cat_2011_2012 <- rec_with_table(
  cchs2011_2012_p,c(
    "HWTGHTM",
    "HWTGWTK",
    "HWTGBMI_der",
    "HWTGBMI_der_cat4"
  )
)

tail(bmi_cat_2011_2012)

combined_bmi_cat <- suppressWarnings(merge_rec_data
(bmi_cat_2009_2010,bmi_cat_2011_2012))

head(combined_bmi_cat)
tail(combined_bmi_cat)