This function creates a categorical derived variable (HWTGBMI_der_cat4) that categorizes derived BMI (HWTGBMI_der).
bmi_fun_cat(HWTGBMI_der)derived variable that calculates numeric value for BMI.
See bmi_fun for documentation on how variable
was derived.
value for BMI categories in the HWTGBMI_der_cat4 variable.
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.
# 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"
)
)
#> No variable_details detected.
#> Loading cchsflow variable_details
#> Using the passed data variable name as database_name
#> NOTE for HWTGHTM: Height is a reported in meters from 2005 CCHS onwards
head(bmi_cat_2009_2010)
#> HWTGHTM HWTGWTK HWTGBMI_der HWTGBMI_der_cat4
#> 1 1.778 54.45 17.22401 1
#> 2 1.702 56.00 19.33165 2
#> 3 1.626 90.00 34.04093 4
#> 4 NA NA NA NA(b)
#> 5 1.880 99.00 28.01041 3
#> 6 1.575 72.00 29.02494 3
bmi_cat_2011_2012 <- rec_with_table(
cchs2011_2012_p,c(
"HWTGHTM",
"HWTGWTK",
"HWTGBMI_der",
"HWTGBMI_der_cat4"
)
)
#> No variable_details detected.
#> Loading cchsflow variable_details
#> Using the passed data variable name as database_name
#> NOTE for HWTGHTM: Height is a reported in meters from 2005 CCHS onwards
tail(bmi_cat_2011_2012)
#> HWTGHTM HWTGWTK HWTGBMI_der HWTGBMI_der_cat4
#> 195 1.600 64.35 25.13672 3
#> 196 1.880 80.10 22.66297 2
#> 197 1.753 78.75 25.62635 3
#> 198 1.651 83.70 30.70657 4
#> 199 1.930 74.25 19.93342 2
#> 200 1.575 76.50 30.83900 4
combined_bmi_cat <- suppressWarnings(merge_rec_data
(bmi_cat_2009_2010,bmi_cat_2011_2012))
head(combined_bmi_cat)
#> HWTGHTM HWTGWTK HWTGBMI_der HWTGBMI_der_cat4
#> 1 1.778 54.45 17.22401 1
#> 2 1.702 56.00 19.33165 2
#> 3 1.626 90.00 34.04093 4
#> 4 NA NA NA NA(b)
#> 5 1.880 99.00 28.01041 3
#> 6 1.575 72.00 29.02494 3
tail(combined_bmi_cat)
#> HWTGHTM HWTGWTK HWTGBMI_der HWTGBMI_der_cat4
#> 395 1.600 64.35 25.13672 3
#> 396 1.880 80.10 22.66297 2
#> 397 1.753 78.75 25.62635 3
#> 398 1.651 83.70 30.70657 4
#> 399 1.930 74.25 19.93342 2
#> 400 1.575 76.50 30.83900 4