E-value for meta-analysis with multiple biases
Usage
multibias_evalue(
yi,
vi,
sei,
cluster = 1:length(yi),
biased = TRUE,
selection_ratio,
q = 0,
favor_positive = TRUE,
alpha_select = 0.05,
ci_level = 0.95,
small = TRUE,
bias_max = 20,
assumed_bias_type = NULL
)
Arguments
- yi
A vector of point estimates to be meta-analyzed.
- vi
A vector of estimated variances (i.e., squared standard errors) for the point estimates.
- sei
A vector of estimated standard errors for the point estimates. (Only one of
vi
orsei
needs to be specified).- cluster
Vector of the same length as the number of rows in the data, indicating which cluster each study should be considered part of (defaults to treating studies as independent; i.e., each study is in its own cluster).
- biased
Boolean indicating whether each study is considered internally biased; either single value used for all studies or a vector the same length as the number of rows in the data (defaults to all studies).
- selection_ratio
Ratio by which publication bias favors affirmative studies (i.e., studies with p-values less than
alpha_select
and estimates in the direction indicated byfavor_positive
).- q
The attenuated value to which to shift the point estimate or CI. Should be specified on the same scale as
yi
(e.g., ifyi
is on the log-RR scale, thenq
should be as well).- favor_positive
TRUE
if publication bias are assumed to favor significant positive estimates;FALSE
if assumed to favor significant negative estimates.- alpha_select
Alpha level at which an estimate's probability of being favored by publication bias is assumed to change (i.e., the threshold at which study investigators, journal editors, etc., consider an estimate to be significant).
- ci_level
Confidence interval level (as proportion) for the corrected point estimate. (The alpha level for inference on the corrected point estimate will be calculated from
ci_level
.)- small
Should inference allow for a small meta-analysis? We recommend always using
TRUE
.- bias_max
The largest value of
bias
, on the additive scale, that should be included in the grid search. The bias has the same units asyi
.- assumed_bias_type
List of biases to consider for computing evalues (objects of
bias
as returned byEValue::confounding()
,EValue::selection()
,EValue::misclassification()
) (defaults to NULL, i.e. agnostic as to the nature of the internal bias). If not NULL, theyi
argument must be on the log-RR scale (ifyi
is not already on that scale, useEValue::convert_measures()
to make it so).
Value
An object of class metabias::metabias()
, a list containing:
- data
A tibble with one row per study and the columns
yi
,vi
,sei
,cluster
,biased
.- values
A list with the elements
selection_ratio
,q
,favor_positive
,alpha_select
,ci_level
,small
,bias_max
.- stats
A tibble with the columns
bias_est
,bias_ci
,evalue_est
,evalue_ci
.
Details
For more on the functions passed as assumed_bias_type
, see the
EValue
package multiple-bias vignette:
vignette("multiple-bias", package = "EValue")
References
Mathur MB (2022). “Sensitivity analysis for the interactive effects of internal bias and publication bias in meta-analyses.” doi:10.31219/osf.io/u7vcb .
Ding P, VanderWeele TJ (2016). “Sensitivity analysis without assumptions.” Epidemiology (Cambridge, Mass.), 27(3), 368.
Smith LH, VanderWeele TJ (2019). “Bounding bias due to selection.” Epidemiology (Cambridge, Mass.), 30(4), 509.
VanderWeele TJ, Li Y (2019). “Simple sensitivity analysis for differential measurement error.” American journal of epidemiology, 188(10), 1823--1829.
Examples
# \donttest{
# specify confounding as internal bias
evalues <- multibias_evalue(yi = meta_meat$yi,
vi = meta_meat$vi,
biased = !meta_meat$randomized,
selection_ratio = 4)
evalues$stats
#> # A tibble: 1 × 2
#> bias_est bias_ci
#> <dbl> <dbl>
#> 1 0.539 0.270
# specify confounding as internal bias
evalues_confounding <- multibias_evalue(yi = meta_meat$yi,
vi = meta_meat$vi,
biased = !meta_meat$randomized,
selection_ratio = 4,
assumed_bias_type = list(EValue::confounding()))
evalues_confounding$stats
#> # A tibble: 1 × 4
#> bias_est bias_ci evalue_est evalue_ci
#> <dbl> <dbl> <dbl> <dbl>
#> 1 0.539 0.270 2.82 1.95
# }