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Calculate p-values with cluster wild bootstrapping for meta-regression models.

Source: R/Wald_test_wildmeta.R
Wald_test_cwb.Rd

Calculate p-values for single coefficient and multiple contrast hypothesis tests using cluster wild bootstrapping.

Usage

Wald_test_cwb(
  full_model,
  constraints,
  R,
  cluster = NULL,
  auxiliary_dist = "Rademacher",
  adjust = "CR0",
  type = "CR0",
  test = "Naive-F",
  seed = NULL,
  future_args = NULL
)

Arguments

full_model

Model fit using robumeta::robu(), metafor::rma.mv(), or metafor::rma.uni() that includes the full set of moderators in the meta-regression model.

constraints

A q X p constraint matrix be tested. Alternately, a function to create such a matrix, specified using clubSandwich::constrain_equal() or clubSandwich::constrain_zero().

R

Number of bootstrap replications.

cluster

Vector of identifiers indicating which observations belong to the same cluster. If NULL (the default), then the clustering variable will be inferred based on the structure of full_mod.

auxiliary_dist

Character string indicating the auxiliary distribution to be used for cluster wild bootstrapping, with available options: "Rademacher", "Mammen", "Webb six", "uniform", "standard normal". The default is set to "Rademacher." We recommend the Rademacher distribution for models that have at least 10 clusters. For models with less than 10 clusters, we recommend the use of "Webb six" distribution.

adjust

Character string specifying which small-sample adjustment should be used to multiply the residuals by. The available options are "CRO", "CR1", "CR2", "CR3", or "CR4", with a default of "CRO".

type

Character string specifying which small-sample adjustment is used to calculate the Wald test statistic. The available options are "CRO", "CR1", "CR2", "CR3", or "CR4", with a default of "CRO".

test

Character string specifying which (if any) small-sample adjustment is used in calculating the test statistic. Default is "Naive-F", which does not make any small-sample adjustment.

seed

Optional seed value to ensure reproducibility.

future_args

Optional list of additional arguments passed to the future_*() functions used in calculating results across bootstrap replications. Ignored if the future.apply package is not available.

Value

A data.frame containing the name of the test, the adjustment used for the bootstrap process, the type of variance-covariance matrix used, the type of test statistic, the number of bootstrap replicates, and the bootstrapped p-value.

Examples

library(clubSandwich)
library(robumeta)

model <- robu(d ~ 0 + study_type + hrs + test,
             studynum = study,
              var.eff.size = V,
              small = FALSE,
              data = SATcoaching)

C_mat <- constrain_equal(1:3, coefs = coef(model))

Wald_test_cwb(full_model = model,
              constraints = C_mat,
              R = 12)
#>   Test Adjustment CR_type Statistic  R     p_val
#> 1  CWB        CR0     CR0   Naive-F 12 0.3333333

# Equivalent, using constrain_equal()
Wald_test_cwb(full_model = model,
              constraints = constrain_equal(1:3),
              R = 12)
#>   Test Adjustment CR_type Statistic  R     p_val
#> 1  CWB        CR0     CR0   Naive-F 12 0.3333333