# Wolfgang Viechtbauer

Marginally significant (p = .07)

### Sidebar

#### Other Sites/Profiles

Note: This course is rather specialized, so I haven't offered it in the past in Maastricht. However, I have taught this course on a number of occasions based on invitations at other universities/institutes and would be happy to do so in the future. Please get in touch if you are interested.

### General Information

 Course Date to be announced Course Location Maastricht, The Netherlands (details below) Registration Deadline to be announced Course Fee see below

### Course Description

The purpose of this course is to cover advanced methods for meta-analysis with particular emphasis on using the statistical software R for conducting the analyses. Therefore, course participants are expected to have an understanding of standard meta-analytic techniques and methodology (see below for course prerequisites).

We will start out by briefly reviewing standard meta-analytic models (i.e., equal-, fixed-, random-, and mixed-effects meta-regression models), focusing on how to fit these models in R. This will then be the starting point to delve into more complex data structures that one may encounter in practice and to consider appropriate models for analyzing such data. Models and techniques to be discussed in this context include multilevel and multivariate models, methods for dealing with dependent/correlated outcomes, network meta-analysis (or what is also known as multiple/mixed treatment comparisons), models with crossed random effects, phylogenetic meta-analysis, and spatio-temporal models. We will also examine the distinction between models that use the normal distribution as an asymptotic approximation to the sampling distribution of the observed outcomes and models that are based on alternative distributional assumptions (e.g., binomial and Poisson distributions, which then lead to random/mixed-effects (conditional) logistic and Poisson regression models).

This is typically a two-day course (starting at 9am and concluding around 5pm on each day), but an abridged one-day version of this course can also be given.

### Course Prerequisites

Course participants are expected to have an understanding of standard meta-analytic methods and ideally some prior experience with analyzing meta-analytic data. Most importantly, participants should be familiar with the computation and interpretation of outcome measures commonly used in meta-analyses (e.g., risk differences, log transformed risk/odds ratios, raw or standardized mean differences, response ratios, raw or Fisher's r-to-z transformed correlations) and the interpretation and application of equal-, fixed-, random-, and mixed-effects meta-regression models. I also offer a three-day meta-analysis course that covers these (and other topics) in great detail.

The primary software package to be used during the course for the analyses will be R (see below for more details). Although all commands to be used for the examples and illustrations will be explained, this is not a comprehensive R programming course. Therefore, if you are new to R, it would be useful to familiarize yourself with R a little bit ahead of time (here are some notes on preparing to use R). You could also consider following the introduction to R course first.

Finally, further below, you will find a list of references, which describe some of the models and methods that will be discussed during the course. If you have the time, feel very ambitious, and don't already know these papers in the first place, it would be ideal to at least skim through them ahead of time in preparation for the course (and to get a better idea of the course contents). But this is not a course prerequisites per se – all of the models and methods to be discussed will be introduced step by step during the course without assuming that you have already read each and every paper listed below.

### What to Bring to the Course

The course is very hands-on and participants will immediately put models and techniques into practice with several illustrative datasets. Therefore, please bring a laptop to the course. Moreover, you should have the current version of R installed on the laptop. More information about R can be found on the R Project Website. You can download R from the Comprehensive R Archive Network (CRAN).

It may also be useful to install an integrated development environment (IDE) for R. A popular choice these days is RStudio, which is available for Windows, MacOS, and Linux.

Once R is installed, please install the metafor package (an add-on package for conducting meta-analyses with R). More details about the package can be found on the metafor package website. If you have an internet connection, you should be able to install the package by starting R and then typing install.packages("metafor") (if you are prompted to choose a mirror, select the default option or a location that is nearby).

In addition, we are likely to make use of a number of additional packages during the course. You should be able to install all of the needed packages at once with the following command (this make take a few moments to complete):

install.packages(c("lme4", "numDeriv", "minqa", "nloptr", "dfoptim", "ucminf", "optimParallel", "CompQuadForm", "mvtnorm", "BiasedUrn", "igraph", "multcomp", "plyr", "ape", "sp"))

You can also pair up with another course participant for the computer exercises, so technically not everybody needs to bring a laptop. However, if at all possible, please bring your own laptop so we don't end up with the unfortunate situation that nobody brings one!

### Course Fee

The course fee is 400 Euros and includes lunch, refreshments (e.g., coffee, tea, water) during the breaks, but not dinner or accommodations.

### Course Location

The course will be held at the Department of Psychiatry and Neuropsychology at Maastricht University in the Netherlands.

#### Department Location

Vijverdalseweg 1
6226 NB Maastricht
The Netherlands

#### Arriving by Car

If you arrive by car, just use the Google Maps Link to obtain directions depending on your starting point. There is a freely accessible parking lot south of the building (where the roads form a P-shape just underneath the building).

#### Arriving by Train/Bus

If you arrive by train, you should leave the train at the main station in Maastricht. Exit the station and take bus number 8 in the direction Valkenburg (careful, the bus only leaves once every hour at hh:52 the last time I checked). Take the bus to the Vijverdal stop (takes about 10 minutes). The building is right across the road from the bus stop.

#### Finding the Department

Follow the walkway between the parking lot and the three-story building to the main entrance (the building is shown below; the walkway is to the left of the building). Inside, follow the signs for "Route 49" (at the reception, go right, then right again, follow the hallway, and then go up the stairs or take the elevator to the second floor). At the door, please ring the bell and wait for somebody to let you in.

#### Hotel Accommodations

If you need hotel accommodations, a useful website for hotel accommodations in and around Maastricht can be found here. Some possible options include the Novotel Hotel, Hotel van der Valk, and Hotel in den Hoof. All three hotels are located around 1.7km from the course location (note that Hotel in den Hoof is really on the outskirts of the city). For a map showing the course location and the location of these hotels, click here.

### References

Begg, C. B., & Pilote, L. (1991). A model for incorporating historical controls into a meta-analysis. Biometrics, 47(3), 899–906. link

Berkey, C. S., Hoaglin, D. C., Antczak-Bouckoms, A., Mosteller, F., & Colditz, G. A. (1998). Meta-analysis of multiple outcomes by regression with random effects. Statistics in Medicine, 17(22), 2537–2550. link

Gleser, L. J., & Olkin, I. (2009). Stochastically dependent effect sizes. In H. Cooper, L. V. Hedges, & J. C. Valentine (Eds.), The handbook of research synthesis and meta-analysis (2nd ed., pp. 357–376). New York: Russell Sage Foundation.

Hasselblad, V. (1998). Meta-analysis of multitreatment studies. Medical Decision Making, 18(1), 37–43. link

Ishak, K. J., Platt, R. W., Joseph, L., Hanley, J. A., & Caro, J. J. (2007). Meta-analysis of longitudinal studies. Clinical Trials, 4(5), 525–539. link

Jackson, D., White, I. R., & Riley, R. D. (2013). A matrix-based method of moments for fitting the multivariate random effects model for meta-analysis and meta-regression. Biometrical Journal, 55(2), 231–245. link

Jackson, D., Barrett, J. K., Rice, S., White, I. R., & Higgins, J. P. (2014). A design-by-treatment interaction model for network meta-analysis with random inconsistency effects. Statistics in Medicine, 33(21), 3639–3654. link

Konstantopoulos, S. (2011). Fixed effects and variance components estimation in three-level meta-analysis. Research Synthesis Methods, 2(1), 61–76. link

Nakagawa, S., & Santos, E. S. A. (2012). Methodological issues and advances in biological meta-analysis. Evolutionary Ecology, 26(5), 1253–1274. link

Salanti, G., Higgins, J. P. T., Ades, A. E., & Ioannidis, J. P. A. (2008). Evaluation of networks of randomized trials. Statistical Methods in Medical Research, 17(3), 279–301. link

Senn, S., Gavini, F., Magrez, D., & Scheen, A. (2013). Issues in performing a network meta-analysis. Statistical Methods in Medical Research, 22(2), 169–189. link

Stijnen, T., Hamza, T. H., & Ozdemir, P. (2010). Random effects meta-analysis of event outcome in the framework of the generalized linear mixed model with applications in sparse data. Statistics in Medicine, 29(29), 3046–3067. link

Trikalinos, T. A., & Olkin, I. (2012). Meta-analysis of effect sizes reported at multiple time points: A multivariate approach. Clinical Trials, 9(5), 610–620. link

van Houwelingen, H. C., Zwinderman, K. H., & Stijnen, T. (1993). A bivariate approach to meta-analysis. Statistics in Medicine, 12(24), 2273–2284. link

van Houwelingen, H. C., Arends, L. R., & Stijnen, T. (2002). Advanced methods in meta-analysis: Multivariate approach and meta-regression. Statistics in Medicine, 21(4), 589–624. link

Viechtbauer, W. (2010). Conducting meta-analyses in R with the metafor package. Journal of Statistical Software, 36(3), 1-48. link