\name{cumul.rma.uni}
\alias{cumul.rma.uni}
\title{Cumulative Meta-Analysis for rma.uni Objects}
\description{
   The function \code{cumul.rma.uni} repeatedly fits the specified model, adding one observation at a time to the model.
}
\usage{
\method{cumul}{rma.uni}(x, order, digits=x$digits, transf=FALSE, targs, \dots)
}
\arguments{
   \item{x}{an object of class \code{"rma.uni"}.}
   \item{order}{optional vector with indices giving the desired order for the cumulative meta-analysis.}
   \item{digits}{integer specifying the number of decimal places to which the printed results should be rounded (the default is to take the value from the object).}
   \item{transf}{optional argument specifying the name of a function that should be used to transform the model coefficients and interval bounds (e.g., \code{transf=exp}). Defaults to \code{FALSE}, which means that no transformation is used.}
   \item{targs}{optional arguments needed by the function specified under \code{transf}.}
   \item{\dots}{other arguments.}
}
\details{
   The model specified by \code{x} must be a model without moderators (i.e., either a fixed- or a random-effects model).
}
\value{
   An object of class \code{c("list.rma","cumul.rma")}. The object is a list containing the following components:
   \item{estimate}{estimated coefficients of the model.}
   \item{se}{standard errors of the coefficients. \code{NA} if \code{transf} is used to transform the coefficients.}
   \item{zval}{test statistics of the coefficients.}
   \item{pval}{p-values for the test statistics.}
   \item{ci.lb}{lower bounds of the confidence intervals for the coefficients.}
   \item{ci.ub}{upper bounds of the confidence intervals for the coefficients.}
   \item{QE}{test statistics for the tests of heterogeneity.}
   \item{QEp}{p-values for the tests of heterogeneity.}
   \item{tau2}{estimated amounts of (residual) heterogeneity (only for random-effects models).}
   \item{I2}{values of \eqn{I^2}.}
   \item{H2}{values of \eqn{H^2}.}

   The object is formated and printed with \code{\link{print.list.rma}}. A forest plot showing the results from the cumulative meta-analysis can be obtained with \code{\link{forest.cumul.rma}}.
}
\author{
   Wolfgang Viechtbauer \email{wvb@metafor-project.org} \cr
   package homepage: \url{http://www.metafor-project.org/} \cr
   author homepage: \url{http://www.wvbauer.com/}
}
\references{
   Chalmers, T. C., & Lau, J. (1993). Meta-analytic stimulus for changes in clinical trials. \emph{Statistical Methods in Medical Research}, \bold{2}, 161--172.

   Lau, J., Schmid, C. H., & Chalmers, T. C. (1995). Cumulative meta-analysis of clinical trials builds evidence for exemplary medical care. \emph{Journal of Clinical Epidemiology}, \bold{48}, 45--57.

   Viechtbauer, W. (2010). Conducting meta-analyses in R with the metafor package. \emph{Journal of Statistical Software}, \bold{36}(3), 1--48. \url{http://www.jstatsoft.org/v36/i03/}.
}
\seealso{
   \code{\link{cumul}}, \code{\link{forest.cumul.rma}}
}
\examples{
### load BCG vaccine data
data(dat.bcg)

### calculate log relative risks and corresponding sampling variances
dat <- escalc(measure="RR", ai=tpos, bi=tneg, ci=cpos, di=cneg, data=dat.bcg)

### random-effects model
res <- rma(yi, vi, data=dat, method="REML")

### cumulative meta-analysis
cumul(res, transf=exp, order=order(dat$year))
}
\keyword{methods}