compute_kmw_ncc: <Private function> Compute KM-type weight for NCC sample...

In nyilin/SamplingDesignTools: Tools for Dealing with Complex Sampling Designs

<Private function> Compute KM-type weight for NCC sample given information on underlying cohort

Description

<Private function> Compute KM-type weight for NCC sample given information on underlying cohort

Usage

compute_kmw_ncc(
  ncc,
  id_name,
  risk_table_manual,
  t_start_name = NULL,
  t_name,
  t_match_name = t_name,
  y_name,
  match_var_names = NULL,
  n_per_case,
  return_risk_table = FALSE,
  km_names = c(".km_prob", ".km_weight")
)

Arguments

ncc	NCC data. A data.frame or a matrix with column names. This data should not include the ID of each matched set, but should include the actual event/censoring time of each subject.
id_name	Name of the column of the subject ID. A string.
risk_table_manual	A data.frame with columns t_event (unique event times, possibly coarsened), n_at_risk (number of subjects at risk at each t_event in the underlying cohort), and additional columns for matching variables, if any. Make sure the matching variables have the same column names as in ncc_cases and match_var_names.
t_start_name	Name of the column for the start time of follow-up. A string. Default is NULL, i.e., every subject started the follow-up at time 0.
t_name	Name of the column of the exact event/censoring time of each subject. Note that for controls, this should not be the time of the event in the same matched set. A string.
t_match_name	Name of the column of event time in each matched set in ncc, possibly coarsened to the same level as t_event in risk_table_manual. A string. Default is t_name, i.e., not coarsened.
y_name	Name of the column of censoring status in each matched set in ncc, with 1 for event and 0 for censoring. A string.
match_var_names	Name(s) of the match variable(s) in ncc_cases used when drawing the NCC. A string vector.
n_per_case	Number of controls matched to each case.
return_risk_table	Whether the risk table should be returned. Default is FALSE.
km_names	Column names for the KM-type probability (the first element) and weight (the second element) computed, if these two columns are to be attached to each subject in the input data. Default is c(".km_prob", ".km_weight").

Value

If return_risk_table = FALSE (the default), returns a data.frame containing all the unique subjects selected in the NCC sample, with a column for the KM-type weight associated with each subject. If return_risk_table = TRUE, returns a list containing this subcohort (dat) and the risk table (risk_table), which is a data.frame containing the distinct (and exact) event time (t_event), matching variables (if any), and the number of subject at risk at each event time in each strata defined by matching variables (n_at_risk).

nyilin/SamplingDesignTools documentation built on Nov. 20, 2022, 8:07 a.m.