Navigating the garden of forking paths for data exclusions in fear conditioning research
- University Medical Center Hamburg-Eppendorf, Germany
- University of Würzburg, Germany
- KU Leuven, Belgium
- University of Amsterdam, Netherlands
- Ruhr University Bochum, Germany
- Utrecht University, Netherlands
- University of Greifswald, Germany
Abstract
In this report, we illustrate the considerable impact of researcher degrees of freedom with respect to exclusion of participants in paradimgs with a learning element. We illustrate this empirically through case examples from human fear conditioning research where the exclusion of 'non-learners' and 'non-responders' is common - despite a lack of consensus on how to define these groups. We illustrate the substantial heterogeneity in exclusion criteria based on a systematic literature search and highlight potential problems and pitfalls of different definitions through case examples based on re-analyses of existing data sets. Based on this, we propose a consensus on evidence-based rather than idiosyncratic criteria including clear guidelines on reporting details. Taken together, we illustrate how flexibility in data collection and analysis can be avoided, which will benefit the robustness and replicability of research findings and can be expected to be applicable to other fields of research that involve a learning element.
Data availability
The minimal data sets (data set 1 and data set 2, both represent re-analysis of existing data), which were analysed during the current study, as well as code for figure production are are available at OSF under https://osf.io/mkxqe/ and DOI 10.17605/OSF.IO/MKXQE.
Article and author information
Author details
Shira Meir Drexler
Christian Josef Merz
Funding
Deutsche Forschungsgemeinschaft (LO 1980/2-1)
- Tina B Lonsdorf
Deutsche Forschungsgemeinschaft (LO 1980/1-1)
- Tina B Lonsdorf
- Rachel Sjouwerman
Deutsche Forschungsgemeinschaft (44541416)
- Tina B Lonsdorf
Deutsche Forschungsgemeinschaft (316803389)
- Christian Josef Merz
Deutsche Forschungsgemeinschaft (WE 5873/1-1)
- Julia Wendt
Deutsche Forschungsgemeinschaft (WE 5873/5-1)
- Julia Wendt
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: Study 1: All participants gave written informed consent to the protocol which was approved by the local ethics committee (PV 5157, Ethics Committee of the General Medical Council Hamburg).Study 2: All participants gave written informed consent to the protocol which was approved by the Ethical Review Board of the German Psychological Association (TL072015).
Copyright
© 2019, Lonsdorf et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Navigating the garden of forking paths for data exclusions in fear conditioning research
eLife 8:e52465.
https://doi.org/10.7554/eLife.52465
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