[From the paper, “Ensuring the quality and specificity of preregistrations” by C.L.S. Veldkamp et al., posted at PsyArXiv Preprints]

“…we evaluated two preregistration formats that are available on the OSF: a lightweight format that maximizes flexibility for the researcher to define preregistration content that is most fitting for their research (“Standard Pre-Data Collection”), and a highly-defined format that provides a specific workflow and instructions for what must be preregistered (“Prereg Challenge”). We evaluated these two preregistration formats for their independent and comparative effectiveness at reducing researcher degrees of freedom in design and analysis that could affect the credibility of statistical inferences.”

“…To evaluate the extent to which Standard Pre-Data Collection Registrations (SPR) and Prereg Challenge Registrations (PCR) restricted potential opportunistic use of Researcher Degrees of Freedom (DFs), we constructed a coding protocol based on 29 of the 34 DFs from Wicherts et al. (2016; Table 1)…”

“…As expected, PCR generally restricted opportunistic use of DFs better than SPR. In addition, we examined for each DF separately whether it was restricted better in PCR or in SPR. Twenty-two of 29 DFs were better restricted by PCR than by SPR, but only 14 of 29 were significantly so (p < .05). Moreover, the median effect size by DFs was 0.17 (corresponding to a small effect size) and only two showed large effects in the expected direction …”

“…our conclusion: Preregistrations will be more effective at restricting researcher degrees of freedom by using protocols with specific, comprehensive instructions about what needs to be reported.”

To read the paper, click here.