Testing an active intervention to deter researchers' use of questionable research practices

Is N-Hacking Ever OK? The consequences of collecting more data in pursuit of statistical significance

Upon completion of an experiment, if a trend is observed that is "not quite significant," it can be tempting to collect more data in an effort to achieve statistical significance. Such sample augmentation or "N-hacking" is condemned because it can lead to an excess of false positives, which can reduce the reproducibility of results. However, the scenarios used to prove this rule tend to be unrealistic, assuming the addition of unlimited extra samples to achieve statistical significance, or doing so when results are not even close to significant; an unlikely situation for most experiments involving patient samples, cultured cells, or live animals. If we were to examine some more realistic scenarios, could there be any situations where N-hacking might be an acceptable practice? This Essay aims to address this question, using simulations to demonstrate how N-hacking causes false positives and to investigate whether this increase is still relevant when using parameters based on real-life experimental settings.

Testing an active intervention to deter researchers' use of questionable research practices

INTRODUCTION

In this study, we tested a simple, active "ethical consistency" intervention aimed at reducing researchers' endorsement of questionable research practices (QRPs).

METHODS

We developed a simple, active ethical consistency intervention and tested it against a control using an established QRP survey instrument. Before responding to a survey that asked about attitudes towards each of fifteen QRPs, participants were randomly assigned to either a consistency or control 3-5-min writing task. A total of 201 participants completed the survey: 121 participants were recruited from a database of currently funded NSF/NIH scientists, and 80 participants were recruited from a pool of active researchers at a large university medical center in the southeastern US. Narrative responses to the writing prompts were coded and analyzed to assist post hoc interpretation of the quantitative data.

RESULTS

We hypothesized that participants in the consistency condition would find ethically ambiguous QRPs less defensible and would indicate less willingness to engage in them than participants in the control condition. The results showed that the consistency intervention had no significant effect on respondents' reactions regarding the defensibility of the QRPs or their willingness to engage in them. Exploratory analyses considering the narrative themes of participants' responses indicated that participants in the control condition expressed lower perceptions of QRP defensibility and willingness.

CONCLUSION

The results did not support the main hypothesis, and the consistency intervention may have had the unwanted effect of inducing increased rationalization. These results may partially explain why RCR courses often seem to have little positive effect.