Apresentação do Prof. Dr. Olavo Bohrer Amaral na Reunião de Editores Científicos do CRICS10, em 04/12/2018
http://crics10.org/eventos/pt/event/reuniao-de-editores-cientificos/
Reprodutibilidade em resultados de pesquisa (Olavo Bohrer Amaral)
1. Olavo B. Amaral
Reunião de Editores Científicos
CRICS10
Dezembro 2018
Research reproducibility
and scientific publication
2. • We are used to hearing that scientific articles are the most
reliable source of evidence to which we have access.
• That said, we have surprisingly little empirical evidence for
this claim.
An established paradigm
8. • 11 published studies:
- 4 mostly replicated
- 3 partially replicated
- 2 non-replicated
- 2 not interpretable
Some numbers
9. An empirical conclusion...
• In the few areas of biomedical science studied, we cannot
presume that most published findings are true.
10. The rotten apple fallacy
• Retractions for misconduct have become more common,
but their frequency does not begin to explain the problem.
11. The standardization fallacy
• An opposite approach is to try to explain irreproducibility by
purely methodological questions that can’t be controlled
across laboratories.
(that said...)
12. Hell is in the grey zone
• The most useful way to
approach irreproducibility
is to look at the grey zone
between methodological
diffficulties and
misconduct.
13. Chance and bias
• With loose statistical standards, the sum of our biases can
easily turn chance into scientific ‘truth’.
14. The tragedy of p < 0.05
• The definition of ‘significance’ used by most life scientists
means that, with enough data and ways to analyze it, one can
prove basically anything.
15. • With sufficient experiments, ‘significant’ results will occur in
1 out of 20 experiments by definition, even if nothing is true.
16. • Analyzing the same experiment in 20 different ways, it is
usually not hard to find a ‘significant’ result either.
18. A basic flaw
Replication
Citations
Impact
Changed plans
Data exploration
Analysis options
Obstacles
Negative results
Failed experiments
Criticism
• When reading a scientific article, we do not know the
original hypotheses, the number of comparisons and the
number of analysis options.
19. Like a Tinder profile
• This is not all that different from other ‘non-scientific’
syntheses of reality.
Replication
Citations
Impact
Changed plans
Data exploration
Analysis options
Obstacles
Negative results
Failed experiments
Criticism
20. Unmasking ‘impact’
• Traditional peer review conflates the evaluation of methods
and results (and of data and stories).
• Beautiful stories with lots of shaky data tend to trump solid,
well-performed experiments.
Volume
Novelty/Impact
- Number of
experiments,
methods, etc.
- Coherence of results
- Novelty of theory
- Potential impact
Rigor/Reproducibility
- Experimental design
- Protocol registration
- Data availability
- Statistical rigor
21. Doomed to fail
• Irreproducibility is the natural outcome in a system in which
impact and novelty count but truth does not.
22. Wrong time, wrong place
• Even when peer review does work, it comes at the wrong
time (after results are in) and behind closed doors.
Registered Reports
23. The death of prepublication peer review?
• It is time to discuss whether prepublication peer review
should not give way to different forms of quality control.
24. Time to experiment
• Do we lose that much by giving up on prepublication peer
review?
Score(%applicableitems)
bioRxiv PubMed
0
20
40
60
80
100
Quality of reporting of methods/results in
preprints vs. peer-reviewed articles
bioRxiv 59.4% vs. 63.9% PubMed
p = 0.019, r2 = 0.036
Carneiro et al., in prep.
https://osf.io/rxqn4/
25. Actual peer review
• We urgently need better data on reproducibility in various
scientific environments.
• 71 lab-strong initiative to reproduce 50-100 experiments from
Brazilian life sciences articles over the last 20 years.
• Each experiment reproduced in 3 labs to estimate interlab
variability.
• http://reprodutibilidade.bio.br
26. No need to fear change
• Unlike with democracy, we have not really tried out anything
different for the last century.
27. Barriers are cultural, not scientific
• Peer review has become more important for science as a form
of branding than of actual quality control.
28. Conclusions
• The current model of article peer review as a barrier to
publication based is more harmful than helpful for science.
• Changing the way we publish science to make it more
reproducible and accessible is an ethical imperative.
• These changes must be accompanied by changes in how we
evaluate science.
• The barriers to change are cultural rather than financial or
technological.
29. The tide is changing
• It is time to decide whether to cling to a sinking ship or to
help building new ones.
• http://asapbio.org