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Replication studies in psychological science sometimes fail to reproduce prior findings. If these studies use methods that are unfaithful to the original study or ineffective in eliciting the phenomenon of interest, then a failure to replicate may be a failure of the protocol rather than a challenge to the original finding. Formal pre-data-collection peer review by experts may address shortcomings and increase replicability rates. We selected 10 replication studies from the Reproducibility Project: Psychology (RP:P; Open Science Collaboration, 2015) for which the original authors had expressed concerns about the replication designs before data collection; only one of these studies had yielded a statistically significant effect (p< .05). Commenters suggested that lack of adherence to expert review and low-powered tests were the reasons that most of these RP:P studies failed to replicate the original effects. We revised the replication protocols and received formal peer review prior to conducting new replication studies. We administered the RP:P and revised protocols in multiple laboratories (median number of laboratories per original study = 6.5, range = 3–9; median total sample = 1,279.5, range = 276–3,512) for high-powered tests of each original finding with both protocols. Overall, following the preregistered analysis plan, we found that the revised protocols produced effect sizes similar to those of the RP:P protocols (Δr= .002 or .014, depending on analytic approach). The median effect size for the revised protocols (r= .05) was similar to that of the RP:P protocols (r= .04) and the original RP:P replications (r= .11), and smaller than that of the original studies (r= .37). Analysis of the cumulative evidence across the original studies and the corresponding three replication attempts provided very precise estimates of the 10 tested effects and indicated that their effect sizes (median r= .07, range = .00–.15) were 78% smaller, on average, than the original effect sizes (median r= .37, range = .19–.50).

Does convincing people that free will is an illusion reduce their sense of personal responsibility? Vohs and Schooler (2008) found that participants reading from a passage “debunking” free will cheated more on experimental tasks than did those reading from a control passage, an effect mediated by decreased belief in free will. However, this finding was not replicated by Embley, Johnson, and Giner-Sorolla (2015), who found that reading arguments against free will had no effect on cheating in their sample. The present study investigated whether hard-to-understand arguments against free will and a low-reliability measure of free-will beliefs account for Embley et al.’s failure to replicate Vohs and Schooler’s results. Participants (N= 621) were randomly assigned to participate in either a close replication of Vohs and Schooler’s Experiment 1 based on the materials of Embley et al. or a revised protocol, which used an easier-to-understand free-will-belief manipulation and an improved instrument to measure free will. We found that the revisions did not matter. Although the revised measure of belief in free will had better reliability than the original measure, an analysis of the data from the two protocols combined indicated that free-will beliefs were unchanged by the manipulations, d= 0.064, 95% confidence interval = [−0.087, 0.22], and in the focal test, there were no differences in cheating behavior between conditions, d= 0.076, 95% CI = [−0.082, 0.22]. We found that expressed free-will beliefs did not mediate the link between the free-will-belief manipulation and cheating, and in exploratory follow-up analyses, we found that participants expressing lower beliefs in free will were not more likely to cheat in our task.

As part of the Many Labs 5 project, we ran a replication of van Dijk, van Kleef, Steinel, and van Beest’s (2008) study examining the effect of emotions in negotiations. They reported that when the consequences of rejection were low, subjects offered fewer chips to angry bargaining partners than to happy partners. We ran this replication under three protocols: the protocol used in the Reproducibility Project: Psychology, a revised protocol, and an online protocol. The effect averaged one ninth the size of the originally reported effect and was significant only for the revised protocol. However, the difference between the original and revised protocols was not significant.

The self-concept maintenance theory holds that many people will cheat in order to maximize self-profit, but only to the extent that they can do so while maintaining a positive self-concept. Mazar, Amir, and Ariely (2008, Experiment 1) gave participants an opportunity and incentive to cheat on a problem-solving task. Prior to that task, participants either recalled the Ten Commandments (a moral reminder) or recalled 10 books they had read in high school (a neutral task). Results were consistent with the self-concept maintenance theory. When given the opportunity to cheat, participants given the moral-reminder priming task reported solving 1.45 fewer matrices than did those given a neutral prime (Cohen’s d= 0.48); moral reminders reduced cheating. Mazar et al.’s article is among the most cited in deception research, but their Experiment 1 has not been replicated directly. This Registered Replication Report describes the aggregated result of 25 direct replications (total N= 5,786), all of which followed the same preregistered protocol. In the primary meta-analysis (19 replications, total n= 4,674), participants who were given an opportunity to cheat reported solving 0.11 more matrices if they were given a moral reminder than if they were given a neutral reminder (95% confidence interval = [−0.09, 0.31]). This small effect was numerically in the opposite direction of the effect observed in the original study (Cohen’s d= −0.04).

Srull and Wyer (1979) demonstrated that exposing participants to more hostility-related stimuli caused them subsequently to interpret ambiguous behaviors as more hostile. In their Experiment 1, participants descrambled sets of words to form sentences. In one condition, 80% of the descrambled sentences described hostile behaviors, and in another condition, 20% described hostile behaviors. Following the descrambling task, all participants read a vignette about a man named Donald who behaved in an ambiguously hostile manner and then rated him on a set of personality traits. Next, participants rated the hostility of various ambiguously hostile behaviors (all ratings on scales from 0 to 10). Participants who descrambled mostly hostile sentences rated Donald and the ambiguous behaviors as approximately 3 scale points more hostile than did those who descrambled mostly neutral sentences. This Registered Replication Report describes the results of 26 independent replications (N= 7,373 in the total sample; k= 22 labs and N= 5,610 in the primary analyses) of Srull and Wyer’s Experiment 1, each of which followed a preregistered and vetted protocol. A random-effects meta-analysis showed that the protagonist was seen as 0.08 scale points more hostile when participants were primed with 80% hostile sentences than when they were primed with 20% hostile sentences (95% confidence interval, CI = [0.004, 0.16]). The ambiguously hostile behaviors were seen as 0.08 points less hostile when participants were primed with 80% hostile sentences than when they were primed with 20% hostile sentences (95% CI = [−0.18, 0.01]). Although the confidence interval for one outcome excluded zero and the observed effect was in the predicted direction, these results suggest that the currently used methods do not produce an assimilative priming effect that is practically and routinely detectable.

The comparative efficacy and safety profiles of selected daily 1000 IU, weekly 7000 IU and monthly 30,000 IU vitamin D3—not previously investigated—will be evaluated. Here, a prospective, randomized clinical trial, comparing efficacy and safety of a daily single dose of 1000 IU (group A) to a once-weekly 7000 IU dose (group B), or monthly 30,000 IU dose (group C) of vitamin D3. The present study is a controlled, randomized, open-label, multicenter clinical trial, 3  months in duration. Sixty-four adult subjects with vitamin D deficiency (25OHD<20 ng/ml), were included according to the inclusion and exclusion criteria. Dose-responses for increases in serum vitamin 25OHD were statistically equivalent for each of the three groups: A, B and C. Outcomes were 13.0 ± 1.5; 12.6 ± 1.1 and 12.9 ± 0.9 ng/ml increases in serum 25OHD per 1000 IU, daily, weekly and monthly, respectively. The treatment of subjects with selected doses restored 25OHD values to levels above 20 ng/ml in all groups. Treatment with distinct administration frequency of vitamin D3did not exhibit any differences in safety parameters. The daily, weekly and monthly administrations of daily equivalent of 1000 IU of vitamin D3provide equal efficacy and safety profiles.