Reproducibility Crisis
What Led to the Replication Crisis in Psychology?
Some scientists have warned for years that certain ways of collecting, analyzing, and reporting data, often referred to as questionable research practices, make it more likely that results will appear to be statistically meaningful even though they are not. Flawed study designs and a “publication bias ” that favors confirmatory results are other longtime sources of concern.
A series of replication projects in the mid-2010s amplified these worries. In one major project, fewer than half of the studies that replicators tried to recreate yielded similar results, suggesting that at least some of the original findings were false positives.
A variety of findings have come into question following replication attempts, including well-known ones suggesting that certain types of priming , physical poses, and other simple interventions could affect behavior in surprising or beneficial ways. It is important to note that psychology is not alone, however: Other fields, such as cancer research and economics, have faced similar questions about methodological rigor.
The growing awareness of how research practices can lead to false positives has coincided with extreme instances of willful misrepresentation and falsification—resulting, in some cases, in the removal or resignation of prominent scientists.
Understanding Research Methods
To better grasp the replication crisis, it’s worth exploring some of the statistical methods used in psychology experiments. Flexibility in research methodology can help explain why researchers unconsciously (and sometimes consciously) produce unreliable results.
When conducting an experiment, a researcher develops a hypothesis. For example, they may hypothesize that spending time with friends makes people happier. They then seek to reject the null hypothesis —the possibility that there is no association or effect of the sort the researchers propose. In this case, the null hypothesis would be that there is no relationship between happiness and spending time with friends.
A finding is said to be statistically significant if the results of a study based on a particular sample of people are thought to be likely to generalize to the broader population of interest. A traditional benchmark of statistical significance in psychology is a p-value of .05, though more stringent benchmarks have recently been proposed.
The p-value is a measure to determine statistical significance. Roughly speaking, a p-value is the probability of obtaining a study result by random chance if the null hypothesis is true. The smaller the p-value, the less likely it is that an observed result would be found in the absence of a real effect or association between variables. The threshold for significance is traditionally a p-value of less than .05 , although the replication crisis has led researchers to rethink relying on p-values or to propose changing the threshold for what counts as "significant" to a lower p-value (such as .005). The fact that .05 is an arbitrary benchmark is, for some, further evidence that p-values are given too much credence.
How Psychology Is Moving Forward
The replication crisis provoked heated internal debate in the field, with some arguing that it called for an overhaul of psychological science and others maintaining that the “crisis” was unreal or overblown. Nevertheless, psychologists interested in reform have pressed ahead with efforts to make the claims of psychological research more credible.
The reformers’ immediate aims include greater transparency in the study planning and data analysis, more routine follow-up testing of results to make sure they can be reliably observed, and study designs that are well-suited to the scientific questions at hand. It remains to be seen which approaches will ultimately be most useful in increasing the veracity of psychological findings.
Psychologists have developed an array of strategies to ensure that future findings have greater credibility. These include conducting more replications of emerging findings, relying on larger sample sizes, and leveraging thoroughly tested measures. Another is preregistration, delineating one’s hypothesis and study plans before conducting a study. Yet another is Registered Reports, in which journals agree to publish a transparently planned-out study no matter the results.
In addition to specific procedures to curb unreliable research practices, many organizations devoted to credibility and transparency have sprung up in the wake of the replication crisis. A few of those initiatives include the Open Science Collaboration , the Society for the Improvement of Psychological Science, and the Psychological Science Accelerator.
Explore More About Replication Crisis
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