Both liberals and conservatives accuse their political opponents of partisan bias, but is there empirical evidence that one side of the political aisle is indeed more biased than the other? To address this question, we meta-analyzed the results of 51 experimental studies, involving over 18,000 participants, that examined one form of partisan bias-the tendency to evaluate otherwise identical information more favorably when it supports one's political beliefs or allegiances than when it challenges those beliefs or allegiances. Two hypotheses based on previous literature were tested: an asymmetry hypothesis (predicting greater partisan bias in conservatives than in liberals) and a symmetry hypothesis (predicting equal levels of partisan bias in liberals and conservatives). Mean overall partisan bias was robust ( r = .245), and there was strong support for the symmetry hypothesis: Liberals ( r = .235) and conservatives ( r = .255) showed no difference in mean levels of bias across studies. Moderator analyses reveal this pattern to be consistent across a number of different methodological variations and political topics. Implications of the current findings for the ongoing ideological symmetry debate and the role of partisan bias in scientific discourse and political conflict are discussed.

This retrospective chart-review study examined patient-level correlates of initiation and completion of evidence-based psychotherapy (EBP) for posttraumatic stress disorder (PTSD) among treatment-seeking U.S. veterans. We identified all patients (N = 796) in a large Veterans Affairs PTSD and anxiety clinic who attended at least 1 individual psychotherapy appointment with 1 of 8 providers trained in EBP. Within this group, 91 patients (11.4%) began EBP (either Cognitive Processing Therapy or Prolonged Exposure) and 59 patients (7.9%) completed EBP. The medical records of all EBP patients (n = 91) and a provider-matched sample of patients who received another form of individual psychotherapy (n = 66) were reviewed by 4 independent raters. Logistic regression analyses revealed that Iraq and Afghanistan veterans were less likely to begin EBP than veterans from other service eras, OR = 0.48, 95% CI = [0.24, 0.94], and veterans who were service connected for PTSD were more likely than veterans without service connection to begin EBP, OR = 2.33, 95% CI = [1.09, 5.03]. Among those who began EBP, Iraq and Afghanistan veteran status, OR = 0.09, 95% CI = [0.03, 0.30], and a history of psychiatric inpatient hospitalization, OR = 0.13, 95% CI = [0.03, 0.54], were associated with decreased likelihood of EBP completion.

The current study examined false memories in the week preceding the 2018 Irish abortion referendum. Participants ( N = 3,140) viewed six news stories concerning campaign events—two fabricated and four authentic. Almost half of the sample reported a false memory for at least one fabricated event, with more than one third of participants reporting a specific memory of the event. “Yes” voters (those in favor of legalizing abortion) were more likely than “no” voters to “remember” a fabricated scandal regarding the campaign to vote “no,” and “no” voters were more likely than “yes” voters to “remember” a fabricated scandal regarding the campaign to vote “yes.” This difference was particularly strong for voters of low cognitive ability. A subsequent warning about possible misinformation slightly reduced rates of false memories but did not eliminate these effects. This study suggests that voters in a real-world political campaign are most susceptible to forming false memories for fake news that aligns with their beliefs, in particular if they have low cognitive ability.

Within the Veterans Health Administration, post-traumatic stress disorder (PTSD) treatment decisions are left to the patient and provider, allowing substantial variability in the way treatment decisions are made. Theorized to increase treatment engagement, shared decision-making interventions provide a standardized framework for treatment decisions. This study sought to develop (phase 1) and pilot test the feasibility and potential effectiveness (phase 2) of a brief shared decision-making intervention to promote engagement in evidence-based PTSD treatment. An initial version of the intervention was developed and then modified according to stakeholder feedback. Participants in the pilot trial were 27 Iraq and Afghanistan Veterans recruited during an intake assessment at a Veterans Affairs PTSD clinic. Participants randomized to the intervention condition (n = 13) participated in a 30-minute shared decision-making session, whereas patients randomized to the usual care condition (n = 14) completed treatment planning during their intake appointment, per usual clinic procedures. Among the 20 study completers, a greater proportion of participants in the intervention condition preferred an evidence-based treatment and received an adequate (≥9 sessions) dose of psychotherapy. Results provide preliminary support for the feasibility and potential effectiveness of the intervention and suggest that larger-scale trials are warranted.

This crowdsourced project introduces a collaborative approach to improving the reproducibility of scientific research, in which findings are replicated in qualified independent laboratories before (rather than after) they are published. Our goal is to establish a non-adversarial replication process with highly informative final results. To illustrate the Pre-Publication Independent Replication (PPIR) approach, 25 research groups conducted replications of all ten moral judgment effects which the last author and his collaborators had "in the pipeline" as of August 2014. Six findings replicated according to all replication criteria, one finding replicated but with a significantly smaller effect size than the original, one finding replicated consistently in the original culture but not outside of it, and two findings failed to find support. In total, 40% of the original findings failed at least one major replication criterion. Potential ways to implement and incentivize pre-publication independent replication on a large scale are discussed

Both liberals and conservatives accuse their political opponents of partisan bias, but is there empirical evidence that one side of the political aisle is indeed more biased than the other? To address this question, we meta-analyzed the results of 51 experimental studies, involving over 18,000 participants, that examined one form of partisan bias --the tendency to evaluate otherwise identical information more favorably when it supports one's political beliefs or allegiances than when it challenges those beliefs or allegiances. Based on previous literature, two hypotheses were tested: an asymmetry hypothesis (predicting greater partisan bias in conservatives than liberals) and a symmetry hypothesis (predicting equal levels of partisan bias in liberals and conservatives). Mean overall partisan bias was robust (r = .245) and there was strong support for the symmetry hypothesis: liberals (r = .235) and conservatives (r = .255) showed no difference in mean levels of bias across studies. Moderator analyses reveal this pattern to be consistent across a number of different methodological variations and political topics. Implications of the current findings for the ongoing ideological symmetry debate, and the role of partisan bias in scientific discourse and political conflict are discussed.

Both liberals and conservatives accuse their political opponents of partisan bias, but is there empirical evidence that one side of the political aisle is indeed more biased than the other? To address this question, we meta-analyzed the results of 51 experimental studies, involving over 18,000 participants, that examined one form of partisan bias— the tendency to evaluate otherwise identical information more favorably when it supports one’s political beliefs or allegiances than when it challenges those beliefs or allegiances. Two hypotheses based on previous literature were tested: an asymmetry hypothesis (predicting greater partisan bias in conservatives than in liberals) and a symmetry hypothesis (predicting equal levels of partisan bias in liberals and conservatives). Mean overall partisan bias was robust (r = .245), and there was strong support for the symmetry hypothesis: Liberals (r = .235) and conservatives (r = .255) showed no difference in mean levels of bias across studies. Moderator analyses reveal this pattern to be consistent across a number of different methodological variations and political topics. Implications of the current findings for the ongoing ideological symmetry debate and the role of partisan bias in scientific discourse and political conflict are discussed.

Three studies investigated lay people's perceptions of the relative strength of various conclusions that a forensic scientist might present about whether two items (fingerprints, biological samples) have a common source. Lay participants made a series of judgments about which of two conclusions seemed stronger for proving the items had a common source. The data were fitted to Thurstone-Mosteller paired comparison models to obtain rank-ordered lists of the various statements and an indication of the perceived differences among them. The results reveal the perceived strength of several types of statements, relative to one another, including verbal statements regarding strength of support (e.g. 'extremely strong support for same source'), source probability statements (e.g. 'highly probable same source'), random match probabilities (e.g. RMP ¼ 1 in 100 000), likelihood ratios, and categorical statements (e.g. 'identification'). These comparisons in turn provide insight into whether particular statements about the strength of forensic evidence convey the intended meaning and will be interpreted in a manner that is justifiable and appropriate.