optrefine (version 1.1.1)

calc_smds: Calculate standardized mean differences for initial and refined strata

Description

Summarizes initial and/or refined strata in terms of standardized mean differences (SMDs).

Usage

calc_smds(
  object = NULL,
  z = NULL,
  X = NULL,
  base_strata = NULL,
  refined_strata = NULL,
  abs = TRUE
)

Value

List with two elements, "base" and "refined", each containing a matrix of standardized mean differences for each stratum (row) and covariate (column).

Arguments

object

an optional object of class strat, typically created using strat() or as a result of a call to prop_strat(). If not provided, z and X must be specified

z

vector of treatment assignment; only used if object is not supplied

X

covariate matrix/data.frame; only used if object is not supplied

base_strata

optional initial stratification for which to calculate SMDs; only used if object is not supplied

refined_strata

optional refined stratification for which to calculate SMDs; only used if object is not supplied

abs

boolean whether to return absolute standardized mean differences or raw values. Default is TRUE for absolute values

Examples

# Choose 800 patients and 5 covariates to work with for the example
set.seed(15)
samp <- sample(1:nrow(rhc_X), 800)
cov_samp <- sample(1:26, 5)

# Let it create propensity score strata for you and then refine them
ref <- refine(X = rhc_X[samp, cov_samp], z = rhc_X[samp, "z"])

# Look at covariate balance for propensity score and refined strata
calc_smds(object = ref)