assign_timepoint.RdGiven a data set that has a measure collected over time and you want to extract, for example the 3 month measurement, this function will find the measure closest to 3 months within a defined window.
assign_timepoint(
data,
id,
ref_date,
measure_date,
timepoints,
windows,
time_units = c("days", "weeks", "months", "years"),
new_var = "timepoint"
)data frame
id variable name, such as "mrn"
baseline or reference date column name
date the measure was collected
vector of timepoint to identify
list of windows around a timepoint that are acceptable
one of c("days", "weeks", "months", "years")
name of new variable, default is "timepoint"
data frame passed in data with additional column new_var
ggplot2::economics_long %>%
dplyr::group_by(variable) %>%
dplyr::mutate(min_date = min(date)) %>%
dplyr::ungroup() %>%
assign_timepoint(
id = "variable",
ref_date = "min_date",
measure_date = "date",
timepoints = c(6, 12, 24),
windows = list(c(-2, 2), c(-2, 2), c(-2, 2)),
time_units = "months"
) %>%
dplyr::filter(!is.na(timepoint))
#> # A tibble: 15 × 4
#> variable min_date date timepoint
#> <chr> <date> <date> <dbl>
#> 1 pce 1967-07-01 1968-01-01 6
#> 2 pce 1967-07-01 1968-07-01 12
#> 3 pce 1967-07-01 1969-07-01 24
#> 4 pop 1967-07-01 1968-01-01 6
#> 5 pop 1967-07-01 1968-07-01 12
#> 6 pop 1967-07-01 1969-07-01 24
#> 7 psavert 1967-07-01 1968-01-01 6
#> 8 psavert 1967-07-01 1968-07-01 12
#> 9 psavert 1967-07-01 1969-07-01 24
#> 10 uempmed 1967-07-01 1968-01-01 6
#> 11 uempmed 1967-07-01 1968-07-01 12
#> 12 uempmed 1967-07-01 1969-07-01 24
#> 13 unemploy 1967-07-01 1968-01-01 6
#> 14 unemploy 1967-07-01 1968-07-01 12
#> 15 unemploy 1967-07-01 1969-07-01 24