\title{studies on nedocromil sodium for preventing exercise-induced bronchoconstriction}
\description{results from 17 trials, 11 studies in children and 6 studies in adults, reporting the maximum fall in the forced expiratory volume in 1 second (fev_1) over the course of follow-up, expressed as a percentage.}
\bold{year}     \tab \code{character} \tab year of publication \cr
\bold{ne}       \tab \code{integer}   \tab number of participants in nedocromil sodium group \cr
\bold{me}       \tab \code{numeric}   \tab maximum fall in the fev_1 (nedocromil sodium) \cr
\bold{se}       \tab \code{numeric}   \tab standard deviation (nedocromil sodium) \cr
\bold{nc}       \tab \code{integer}   \tab number of participants in placebo group \cr
\bold{mc}       \tab \code{numeric}   \tab maximum fall in the fev_1 (placebo) \cr
\bold{agegroup} \tab \code{factor}    \tab age group (children or adults) \cr
\bold{order}    \tab \code{numeric}   \tab order of studies in table 1.1 in the cochrane review
spooner et al. (2002) conducted a cochrane review comparing nedocromil sodium (experimental treatment) with placebo (control) for preventing exercise-induced bronchoconstriction. primary outcome was the maximum fall in the forced expiratory volume in 1 second (fev_1) over the course of follow-up, expressed as a percentage. this outcome is available for 17 studies, 11 studies in children and 6 studies in adults. for each study, the mean value, standard deviation, and sample size are reported for both the experimental and control group. the authors conducted a random-effects meta-analysis with the mean difference as effect measure, i.e.\ mean value in the nedocromil sodium group minus mean value in the placebo group.
spooner, c., saunders, l. d., & rowe, b. h. (2002). nedocromil sodium for preventing exercise‐induced bronchoconstriction. \emph{cochrane database of systematic reviews}, \bold{1}, cd001183. \verb{https://doi.org/10.1002/14651858.cd001183}
### conduct random effects meta-analysis with age subgroups
data = dat.spooner2002, studlab = paste(author, year),
subgroup = agegroup, print.subgroup.name = false,
label.e = "nedocromil sodium", label.c = "placebo",