This function creates a derived variable (time_quit_smoking_der) that calculates the approximate time a former smoker has quit smoking based on various CCHS smoking variables. This variable is for CCHS respondents in CCHS surveys 2003-2014.

time_quit_smoking_fun(SMK_09A_B, SMKG09C)

Arguments

SMK_09A_B

number of years since quitting smoking. Variable asked to former daily smokers who quit <3 years ago.

SMKG09C

number of years since quitting smoking. Variable asked to former daily smokers who quit >=3 years ago.

Value

value for time since quit smoking in time_quit_smoking_der.

Examples

# Using time_quit_smoking_fun() to create pack-years values across CCHS 
# cycles.
# time_quit_smoking_fun() is specified in variable_details.csv along with the
# CCHS variables and cycles included.

# To transform time_quit_smoking across cycles, use rec_with_table() for each
# CCHS cycle and specify time_quit_smoking, along with each smoking variable.
# Then by using merge_rec_data(), you can combine time_quit_smoking across
# cycles.

library(cchsflow)

time_quit2009_2010 <- rec_with_table(
  cchs2009_2010_p, c(
    "SMK_09A_B", "SMKG09C", "time_quit_smoking"
  )
)
#> No variable_details detected.
#>               Loading cchsflow variable_details
#> Using the passed data variable name as database_name
#> NOTE for SMKG09C: Don't know (7) and refusal (8) not included in CCHS 2015-2016 and CCHS 2017-2018

head(time_quit2009_2010)
#>   SMK_09A_B SMKG09C time_quit_smoking
#> 1     NA(a)   NA(a)                NA
#> 2     NA(a)   NA(a)                NA
#> 3     NA(a)   NA(a)                NA
#> 4         4       2                 8
#> 5         4       3                12
#> 6         4       3                12

time_quit2011_2012 <- rec_with_table(
  cchs2011_2012_p, c(
    "SMK_09A_B", "SMKG09C", "time_quit_smoking"
  )
)
#> No variable_details detected.
#>               Loading cchsflow variable_details
#> Using the passed data variable name as database_name
#> NOTE for SMKG09C: Don't know (7) and refusal (8) not included in CCHS 2015-2016 and CCHS 2017-2018

tail(time_quit2011_2012)
#>     SMK_09A_B SMKG09C time_quit_smoking
#> 195         4       3                12
#> 196     NA(a)   NA(a)                NA
#> 197     NA(a)   NA(a)                NA
#> 198         4       2                 8
#> 199     NA(a)   NA(a)                NA
#> 200     NA(a)   NA(a)                NA

combined_time_quit <- suppressWarnings(merge_rec_data(time_quit2009_2010,
 time_quit2011_2012))

head(combined_time_quit)
#>   SMK_09A_B SMKG09C time_quit_smoking
#> 1     NA(a)   NA(a)                NA
#> 2     NA(a)   NA(a)                NA
#> 3     NA(a)   NA(a)                NA
#> 4         4       2                 8
#> 5         4       3                12
#> 6         4       3                12
tail(combined_time_quit)
#>     SMK_09A_B SMKG09C time_quit_smoking
#> 395         4       3                12
#> 396     NA(a)   NA(a)                NA
#> 397     NA(a)   NA(a)                NA
#> 398         4       2                 8
#> 399     NA(a)   NA(a)                NA
#> 400     NA(a)   NA(a)                NA