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    LSM - Sample Size Calculation using GPower (3+2 hours)

    Wednesday, 15 May, 2019 - 09:30 to Wednesday, 15 May, 2019 - 15:30
    Campus: Brussels Health Campus
    Jette campus, Informatica lokaal 2
    Informatica lokaal 2

    Target audience: PhD students and Post-Docs.

    Place: Jette campus, Informatica lokaal 2

    Date/Time: 15 May 2019

    part 1:   9:30-12:30

    part 2: 13:30-15:30 [optional – more info below]

    Sandwich lunch and coffee break drinks are provided.

    Format: instructor-led presentation, peer-to-peer exercises

    Language of instruction: English

    Max. participants: 20

    Instructors: Wilfried Cools (ICDS) & Sven Van Laere (BiSI)

    Sample size can be calculated to ensure that a study will provide sufficient information to answer the questions of interest. This workshop aims to introduce researchers to this topic of sample size calculation, both in theory and practice.  

    Concepts related to sample size calculation like power, effect sizes, and error types are discussed and exemplified using the free tool GPower. Small exercises with GPower challenges participants to reason with these concepts and offer relevant practice.

    A first part (3 hours) addresses the main ideas in sample size calculation for an independent means t-test. A second and optional part (2 hours) will offer, for those interested, an introduction to various extensions, including t-tests for paired data and ANOVA.

    Completion of this workshop will allow participants to do sample size calculations themselves using GPower for simple but common research settings. It will also prepare participants for a more advanced workshop on sample size calculation in the future.


    The workshop on sample size calculations is an advanced workshop which requires participants to understand statistics on a level that allows daily use in research. In particular, for this workshop, participants should understand what a t-test does, and how to interpret its results. When in doubt, please consider the entry-level questions below to ensure yourself that this workshop is suitable for you. Participation in the optional part two is only allowed for those that already participated in part one.

    If you want to use your own device; GPower should be downloaded and ready to use on your laptop. PC with GPower installed will be provided.

    Download G*Power for Windows XP, Vista, 7, 8, and 10 (about 20 MB) here. Please make sure to choose “unpack with folders” in your unzip tool.

    Download G*Power for Mac OS X 10.7 to 10.13 (about 2 MB) here.

    The most recent version of G*Power can be found on http://www.gpower.hhu.de/


    Register here

    Priority will be given to PhDs and Post-docs of the VUB, but others interested can apply as well.

    Entry-level questions:

    Please check out these examples to verify for yourself whether you have a sufficient understanding of distributions and t-tests to participate in this workshop on sample size calculations.


    We kindly ask you to register only once and only when you can actually participate. In case you have already registered but are not able to participate, please be so kind as to notify us by sending an e-mail to lsm@vub.be so we can offer your place to one of your PhD/Post-doc colleagues on the waiting list.

    Please be aware of the fact that the cancellation and no-show policy of VUB applies. Cancellation of your participation is only allowed up to 48 hours before the start of the course. Otherwise, the policy as described on the doctoral school website will be followed.

    Registration Rules: https://student.vub.be/en/phd/doctoral-training#registration
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