In recent years, since the early 2010s, the scientific community has drawn attention to the existence of a crisis of replicability in science, especially in psychology and medicine: the results of many investigations are impossible to replicate or there are simply no attempts to do so.
However, the problems related to the confirmation of hypotheses are not the only ones that are included in the replication crisis, but rather it has a broader nature. In this sense, it is worth highlighting the relevance of the falsification of results, particularly in the field of social psychology, and other very significant methodological factors.
One of the foundations of the scientific method is the replication of results. Although many people have a marked tendency to take the conclusions of a single study as credible and definitive, the truth is that a hypothesis only becomes truly solid when it is confirmed by several valid studies from different research teams.
In the same sense, negative results, that is, the refutation of hypotheses, are as important as their verification. However, the proportion of studies that refute approaches seems to have been reduced in science in general; Consequently, there is a clear primacy of publications that corroborate experimental hypotheses.
Many of the publications that have been carried out around the replication crisis highlight the magnitude that it has taken on psychology. However, it is necessary to explain that This crisis affects science as a whole and that also has a particular intensity in the case of medicine. This is due to a number of interrelated factors.
A meta-analysis carried out by Daniele Fanelli (2009) concludes that publication fraud is more common in medical and pharmaceutical research than in the rest of the fields. The author suggests that this may be due to the large magnitude of financial incentives for publications or a greater degree of awareness in these areas.
There are, however, various factors that influence the replicability crisis beyond the explicit falsification of data. One of the most significant is the selectivity of the publications: in general, positive and striking results have a greater potential to appear in journals and provide recognition and money to researchers.
This is why the “box effect” frequently occurs, whereby Studies that do not support the expected hypotheses are discarded while those that do are selected by the authors and more commonly published. Furthermore, non-replication of positive studies reduces the risk of hypotheses being refuted.
Other common practices that have similar objectives are selecting a large number of variables and then focusing only on those that correlate, modifying sample sizes (for example, including subjects until the results are positive), or carrying out multiple statistical analyzes and report exclusively on those that support the hypotheses.
Why is it so serious in psychology?
The replication crisis in psychology is considered to date back to the early 2010s. During this period Numerous cases of fraud emerged involving relevant authors ; For example, social psychologist Diederik Stapel falsified the results of several publications
A meta-analysis by Makel, Plucker, and Hegarty (2012) found that only about 1% of psychology studies published since the beginning of the 20th century are replications of previous studies. This is a very low figure since it strongly suggests that many of the conclusions obtained by isolated studies cannot be taken as definitive.
The number of successful independent replications is also low, standing around 65%; On the other hand, more than 90% of those carried out by the original research team corroborate the hypotheses. On the other hand, works with negative results are also especially rare in psychology; The same can be said of psychiatry.
Solutions to the research crisis
The crisis of replicability in psychology and science in general not only compromises the results of a large number of studies, but can lead to the legitimation of hypotheses that have not been confirmed with the necessary rigor. This could lead to the widespread use of incorrect hypotheses, altering the development of science.
Currently there are many economic interests (and others also related to prestige) that favor the maintenance of the replication crisis. As long as the criteria followed regarding the publication of studies and the dissemination of their results in large media continue to have this monetarist character, the situation will hardly change.
Most of the proposals that have been made to help solve this crisis are associated with the rigor in the methodology in all its phases, as well as with the participation of other members of the scientific community; In this way, the aim would be to enhance the “peer-review” process and try to encourage replication efforts.
Concluding
It must be taken into account that in the field of psychology we work with many variables, on the one hand, and it is difficult to establish a context in which the starting point is similar to that of another study, on the other. This makes it very easy for elements that are not taken into account in the research to “contaminate” the results.
On the other hand, the limitations of the ways in which it is decided whether there are real phenomena or only statistical phenomena mean that false positives sometimes appear: the simple fact that the p value is significant does not have to be enough to indicate that it reflects a real psychological phenomenon.
