Principles for Designing Randomized Preventive Trials in Mental Health: An Emerging Developmental Epidemiology Paradigm

An emerging population-based paradigm is now being used to guide the design of preventive trials used to test developmental models. We discuss elements of the designs of several ongoing randomized preventive trials involving reduction of risk for children of divorce, for children who exhibit behavioral or learning problems, and for children whose parents are being treated for depression. To test developmental models using this paradigm, we introduce three classes of design issues: design for prerandomization, design for intervention, and design for postintervention. For each of these areas, we present quantitative results from power calculations. Both scientific and cost implications of these power calculations are discussed in terms of variation among subjects on preintervention measures, unit of intervention, assignment, balancing, number of pretest and posttest measures, and the examination of moderation effects.     

Party Identification in Emotional and Political Context: A Replication

While testing an affective measure of party identification Burden and Klofstad (2005 ) found that using the phrase, "feel that you are," in place of, "think of yourself as," significantly shifted PID in a Republican direction. I adopt the theoretical framework of Affective Intelligence ( Marcus, Neuman, & MacKuen, 2000 ) to specify how the timing of their question-wording experiment may have influenced the results. I suggest that the outcome was a function of (a) anxiety present during the survey, which ran just after 9/11 of 2001, coupled with (b) a political environment that favored Republicans. In a 2005 survey I replicate the experiment and collect new measures with which to test expectations. I find no significant shift in PID, and provisional support for the Affective Intelligence explanation. The results validate Burden and Klofstad's measure, qualify their findings, and test the application of the theory of Affective Intelligence to party dispositions. Alternative explanations and directions for further research are discussed.     

Oral approach‐avoidance: A replication and extension for European–Portuguese phonation

Previous research revealed that mouth movements influence attitudes. Covert subvocal articulations inducing muscular contractions resembling ingestion movements were preferred over expectoration‐like movements, unveiling a relationship between vocal muscles' wandering and motivational states such as approach and avoidance. These findings, explained in terms of embodied cognition, suggest that specific movements are directly connected to, and more importantly, automatically activate concordant motivational states. The oral approach‐avoidance effect was replicated using the original stimulus set and a new set of stimulus developed for Portuguese. Results from two high‐powered (total N = 407), independent replications, revealed that the preference for inward words (over outwards) exists in both sets but to a greater extent in the pool phonetically adapted for Portuguese.     

Addressing selective attrition in the enhanced response time‐based concealed information test: A within‐subject replication

The response time‐based concealed information test can reveal when a person recognizes a relevant item among other, irrelevant items, based on comparatively slower responding. Thereby, if a person is concealing the knowledge about the relevance of this item (e.g., recognizing it as a murder weapon), this deception can be revealed. A recent study, conducted online and using a between‐subject design, introduced a significantly enhanced version by including additional items in the task. While this modified version outperformed the original version, it also resulted in a much higher rate of participant dropouts (i.e., participants leaving the experiment's website without completing the task). The grave implication is that the perceived enhancement is perhaps merely due to selective attrition. Therefore, the current experiment replicates the original one, but using a within‐subject design. The results show that there is a large enhancement even when selective attrition is prevented.     

Sidman or statistics?

Murray Sidman's statements regarding variability, experimental control, and generality are interwoven with examples from the literature on conditional discrimination. Sidman's position was that statistical inferences from group studies produce no information about the behavior of individual subjects and that statistical treatment of individual subject data masks variability which may represent conditions that are not controlled. Sidman's work on conditional discrimination provides excellent examples of how complex discriminations should be examined in detail with accuracy levels obtained for each type of discrimination within an experiment. Sidman made important contributions to the foundation of behavior analysis with extensive basic research as well as applications of methods and principles to clinical and educational settings.     

The first direct replication on using verbal credibility assessment for the detection of deceptive intentions

Verbal deception detection has gained momentum as a technique to tell truth‐tellers from liars. At the same time, researchers' degrees of freedom make it hard to assess the robustness of effects. Replication research can help evaluate how reproducible an effect is. We present the first replication in verbal deception research whereby ferry passengers were instructed to tell the truth or lie about their travel plans. The original study found truth‐tellers to include more specific time references in their answers. The replication study that closely mimicked the setting, procedure, materials, coding, and analyses found no lie–truth difference for specific time references. Although the power of our replication study was suboptimal (0.77), Bayesian statistics showed evidence in favor of the null hypothesis. Given the great applied consequences of verbal credibility tests, we hope this first replication attempt ignites much needed preregistered, high‐powered, multilab replication efforts.     

Priming Risky Choice: Do Risk Preferences Need Inferences?

The notion that subtle influences, often falling outside awareness, can bias behaviour has a strong grip on both theoretical perspectives and the public imagination. We report three experiments that examined this idea in the context of risky choice. Experiment 1 (N = 100) appeared to find evidence for an interaction whereby participants primed but not reminded of the prime showed an assimilation effect (e.g. participants primed to be risk seeking became more risk seeking) whereas those who were primed and reminded showed a contrast effect (e.g. became less risk seeking). However, two further experiments (N = 180, N = 128) failed to find any evidence for this interaction, and none of the experiments found evidence for the asymmetry in awareness predicted by an ‘unconscious’ assimilation but ‘conscious’ contrast account. The data were analysed using both Null Hypothesis Significance Testing and Bayesian methods, and the implications of the conclusions arising from each are discussed. Whatever one's statistical predilection, the results imply a reduction of confidence in the belief that risk preferences need no inferences. Copyright © 2016 John Wiley & Sons, Ltd.     

FIELD REPLICATION OF CLASSWIDE PEER TUTORING

We conducted a large-scale field replication study of classwide peer tutoring applied to spelling instruction (Greenwood, Delquadri, & Hall, 1984). Two hundred and eleven inner-city students in four schools participated during their first- and second-grade school years. The effects of classwide peer tutoring were compared to teacher instructional procedures and pretest probes using a group replication design (Barlow, Hayes, & Nelson, 1984). Analysis of group and individual results indicated that (a) both teacher instructional procedures and classwide peer tutoring were effective in increasing spelling performance above pretest levels, (b) peer tutoring produced statistically greater gains relative to the teachers' procedures for both low and high student groups formed on pretest levels, (c) these outcomes were representative of groups, classes, individuals, and years during the project, and (d) participant satisfaction with the program was generally high. A separate analysis of the social importance of treatment outcome revealed differential findings for low and high groups related to pretest levels. Implications of these findings are discussed.     

Robustness of the rule-learning effect in 7-month-old infants: A close,multicenter replication of Marcus et al. (1999)

We conducted a close replication of the seminal work by Marcus and colleagues from 1999, which showed that after a brief auditory exposure phase, 7-month-old infants were able to learn and generalize a rule to novel syllables not previously present in the exposure phase. This work became the foundation for the theoretical framework by which we assume that infants are able to learn abstract representations and generalize linguistic rules. While some extensions on the original work have shown evidence of rule learning, the outcomes are mixed, and an exact replication of Marcus et al.'s study has thus far not been reported. A recent meta-analysis by Rabagliati and colleagues brings to light that the rule-learning effect depends on stimulus type (e.g., meaningfulness, speech vs. nonspeech) and is not as robust as often assumed. In light of the theoretical importance of the issue at stake, it is appropriate and necessary to assess the replicability and robustness of Marcus et al.'s findings. Here we have undertaken a replication across four labs with a large sample of 7-month-old infants (N = 96), using the same exposure patterns (ABA and ABB), methodology (Headturn Preference Paradigm), and original stimuli. As in the original study, we tested the hypothesis that infants are able to learn abstract “algebraic” rules and apply them to novel input. Our results did not replicate the original findings: infants showed no difference in looking time between test patterns consistent or inconsistent with the familiarization pattern they were exposed to.     

A replication of the use of public posting in traffic speed control

In an attempt to replicate several previous studies, a reversal design was used to assess the effects of publicly posted feedback on vehicle speed reduction. The intervention phases consisted of daily posted feedback that supplied drivers with either accurate or inaccurate information regarding the percentage of vehicles exceeding the speed limit on the road. Results from the two feedback conditions indicated no speed reduction in comparison to baseline levels. These results are discussed in light of previous studies that found strong effects for such feedback. Baseline levels of driver compliance and methodological differences may limit the effectiveness of posted feedback in reducing speeding.