mvmeta (version 0.4.7)

summary.mvmeta: Summarizing mvmeta Models

Description

Print and summary method functions for fitted univariate or multivariate meta-analytical models represented in objects of class "mvmeta".

Usage

"summary"(object, ci.level=0.95, ...)
"print"(x, digits=4, ...)
"print"(x, digits=4, ...)

Arguments

object

an object of class "mvmeta" produced by a call to mvmeta.

x

an object of class "mvmeta" or "summary.mvmeta", produced by calls to mvmeta or summary.mvmeta, respectively.

ci.level

a numerical value between 0 and 1, specifying the confidence level for the computation of confidence intervals.

digits

an integer specifying the number of digits to which printed results must be rounded.

...

further arguments passed to or from other methods.

Value

The summary method function for mvmeta objects produces a list of class "summary.mvmeta". The components of the lists are some of those stored in the related mvmeta object, plus the following:

coefficients

a matrix reporting point estimates, standard errors, z statistics and related p-values of the test, and confidence intervals for the $kp$ fixed-effects coefficients. Note this is different than the component with the same name stored in mvmeta objects, simply reporting the point estimates (see mvmetaObject).

AIC

the value of the Akaike information criterion for the fitted mvmeta model, obtained through a call to AIC.

BIC

the value of the Bayesian information criterion for the fitted mvmeta model, obtained through a call to BIC.

corFixed

the $kp x kp$ correlation matrix of the fixed-effects coefficients, obtained from the (co)variance matrix vcov (see mvmetaObject and vcov).

corRandom

the $k x k$ correlation matrix of the random effects, obtained from the between-study (co)variance matrix Psi (see see mvmetaObject).

qstat

results from the Cochran Q test for heterogeneity, namely a list corresponding to a qtest.mvmeta object without its class, obtained through qtest.

ci.level

the confidence level used for defining the confidence intervals for the estimates of the fixed-effects coefficients.

As usual, the print method functions for classes "mvmeta" and "summary.mvmeta" do not return any value.

Details

The print method function for class "mvmeta" only returns basic information on the fitted model, namely the call, estimated fixed-effects coefficients, dimensions and fit statistics (log-likelihood, AIC, BIC).

The summary method function computes additional statistics and tests, and produces a list object of class "summary.mvmeta". The print method function for this class shows additional information, such as tables reporting the estimates for the fixed and random-effects parts of the model, Cochran Q test for heterogeneity and $I^2$.

References

Gasparrini A, Armstrong B, Kenward MG (2012). Multivariate meta-analysis for non-linear and other multi-parameter associations. Statistics in Medicine. 31(29):3821--3839. [Freely available here].

See Also

See mvmeta and mvmetaObject.

Examples

# RUN THE MODEL 
model <- mvmeta(cbind(PD,AL)~pubyear,S=berkey98[5:7],data=berkey98)

# SIMPLE PRINT
model
# DEFINE DIGITS
print(model,digit=2)
# SUMMARY WITH 80TH CONFIDENCE INTERVALS
summary(model,ci.level=0.80)