| Prepare_data {wcox} | R Documentation |
Prepare data for weight calculation using the population incidence.
Description
This function prepares the sample data for weight calculation using external information, i.e. the incidence in the population.
Usage
Prepare_data(dat, population_incidence, breaks)
Arguments
dat |
Data.frame with one row per individual which at least includes a column d with event indicator (1 for event, 0 for censored), a column y with event/censoring time. |
population_incidence |
A vector (in combination with breaks) or a data.frame (columns 1) 'start age group', 2) 'end age group', 3)'S_pop') with population incidence per 100,000 per interval k. |
breaks |
Cut-points for the (age/time) groups. Only needed when population_incidence is a vector. |
Details
Weights are based on a comparison between the survival between sample and population. Therefore, besides the sample data, the population incidence rate (per 100 000) is needed as input, as well as the cut-offs of the (age/time-to-event) groups for which this is available, unless this is provided in a data.frame.
Value
Data.frame ready for weight calculation using function 'Calculate_weights()': one row per individual and a.o. columns id unique ID; d non-censoring indicator; k interval of (age) group; S_k population interval-based proportion of individuals experiencing the event in intervals later than k; S_k. sample proportion of individuals experiencing the event in intervals later than k.