A Pilot Randomized Controlled Trial of an mHealth Intervention to Improve PrEP Adherence Among Young Sexual Minority Men.

This randomized controlled study assessed the feasibility, acceptability, and preliminary impact of the PrEP iT! mHealth intervention designed to improve PrEP adherence among young men who have sex with men (YMSM). A national sample of 80 YMSM in the U.S. (Mage = 25 years; 54% racial/ethnic minority), recruited through social media ads, were randomized to either the PrEP iT! or usual PrEP care conditions. Participants completed online surveys and submitted self-collected dried blood sample (DBS) data as measures of PrEP adherence. Differences in PrEP adherence across treatment arms and between participants with high versus low engagement in PrEP iT! were assessed. Retention was high at the three (94%) and six (93%) month assessment, and participants in PrEP iT! reported satisfactory acceptability of the intervention. There were no significant differences in self-reported or DBS-derived PrEP adherence between randomized groups. However, YMSM in the PrEP iT! group with high PrEP adherence (the equivalent of four or more doses/week through self-report and DBS-derived measures) demonstrated significantly higher engagement in the intervention than those with low PrEP adherence (the equivalent of 3 or fewer doses/week). Overall, the PrEP iT! intervention demonstrated strong feasibility and acceptability. The finding that high PrEP iT! intervention engagement was associated with protective levels of PrEP adherence suggests it is a viable adherence support tool that should be further evaluated in definitive trial among YMSM who need basic support, or as part of a more comprehensive adherence support package for those who need greater assistance.Trial registration Clinical Trials # NCT04509076 (registered August 10, 2020).

Bayesian Analysis of Multi-Factorial Experimental Designs Using SEM.

Latent repeated measures ANOVA (L-RM-ANOVA) has recently been proposed as an alternative to traditional repeated measures ANOVA. L-RM-ANOVA builds upon structural equation modeling and enables researchers to investigate interindividual differences in main/interaction effects, examine custom contrasts, incorporate a measurement model, and account for missing data. However, L-RM-ANOVA uses maximum likelihood and thus cannot incorporate prior information and can have poor statistical properties in small samples. We show how L-RM-ANOVA can be used with Bayesian estimation to resolve the aforementioned issues. We demonstrate how to place informative priors on model parameters that constitute main and interaction effects. We further show how to place weakly informative priors on standardized parameters which can be used when no prior information is available. We conclude that Bayesian estimation can lower Type 1 error and bias, and increase power and efficiency when priors are chosen adequately. We demonstrate the approach using a real empirical example and guide the readers through specification of the model. We argue that ANOVA tables and incomplete descriptive statistics are not sufficient information to specify informative priors, and we identify which parameter estimates should be reported in future research; thereby promoting cumulative research.

Repeated Measures ANOVA with Latent Variables to Analyze Interindividual Differences in Contrasts.

Repeated measures analysis of variance (RM-ANOVA) is a broadly used statistical method to analyze data from experimental designs. RM-ANOVA aims at investigating effects of experimental conditions (i.e., factors) and predictors that affect the outcome of interest. It mainly considers contrasts that test standard main and interaction effects, even though more complex contrasts can in principle be used. Analyses, however, only focus on drawing conclusions about average effects and do not take into consideration interindividual differences in these effects. We propose an alternative approach to RM-ANOVA for analyzing repeated measures data, termed latent repeated measures analysis of variance (L-RM-ANOVA). The new approach is based on structural equation modeling and extends the latent growth components approach. L-RM-ANOVA enables the researcher to not only consider mean differences between different experimental conditions (i.e., average effects), but also to investigate interindividual differences in effects. Such interindividual differences are considered with regard to standard main and interactions effects and also with regard to customized contrasts that allow for testing specific hypotheses of interest. Furthermore, L-RM-ANOVA can include a measurement model for latent variables and can be used for the analysis of complex multi-factorial repeated measures designs. We conclude the presentation by demonstrating L-RM-ANOVA using a minimal repeated measures example.

Integrating minority stress theory and the tripartite influence model: A model of eating disordered behavior in sexual minority young adults.

Eating disorders are serious mental illnesses associated with high mortality rates and health complications. Prior research has found increased rates of eating pathology in sexual minority (SM; e.g., lesbian, gay, bisexual) individuals compared to sexual majority (i.e., heterosexual) individuals. Two prominent models have potential to explain these differences: the tripartite influence model and minority stress theory. While both models separately have promise for explaining the pathway of eating disordered behavior in SM individuals, research has indicated that both models have unexplained variance. Therefore, a comprehensive, integrative model could further explain unique variance. 479 men and 483 women between 18 and 30 years old were recruited through Qualtrics; all participants endorsed attraction to same-gender partners. Two models were estimated by gender using structural equation modeling. For men and women, community involvement accelerated the positive association of heterosexist discrimination with internalized homophobia. Minority stressors were associated with dissatisfaction and muscularity behavior, indicating the importance of incorporating minority stress. For women, community involvement accelerated both the association of pressures with muscularity internalization and the association of muscularity-based dissatisfaction with muscle building behaviors. If confirmed by prospective studies, this model could help refine prevention and intervention efforts with this vulnerable population.

Predicting psychosis-spectrum diagnoses in adulthood from social behaviors and neighborhood contexts in childhood.

Research showing that risk for schizophrenia, bipolar disorder with psychosis, and other psychosis-spectrum diagnoses in adulthood is multidetermined has underscored the necessity of studying the additive and interactive factors in childhood that precede and predict future disorders. In this study, risk for the development of psychosis-spectrum disorders was examined in a 2-generation, 30-year prospective longitudinal study of 3,905 urban families against a sociocultural backdrop of changing economic and social conditions. Peer nominations of aggression, withdrawal, and likeability and national census information on neighborhood-level socioeconomic disadvantage in childhood, as well as changes in neighborhood socioeconomic conditions over the lifespan, were examined as predictors of diagnoses of schizophrenia, bipolar disorder, and other psychosis-spectrum disorders in adulthood relative to developing only nonpsychotic disorders or no psychiatric disorders. Individuals who were both highly aggressive and highly withdrawn were at greater risk for other psychosis-spectrum diagnoses when they experienced greater neighborhood disadvantage in childhood or worsening neighborhood conditions over maturation. Males who were highly aggressive but low on withdrawal were at greater risk for schizophrenia diagnoses. Childhood neighborhood disadvantage predicted both schizophrenia and bipolar diagnoses, regardless of childhood social behavior. Results provided strong support for multiple-domain models of psychopathology, and suggest that universal preventive interventions and social policies aimed at improving neighborhood conditions may be particularly important for decreasing the prevalence of psychosis-spectrum diagnoses in the future.

APOE modifies the interaction of entorhinal cerebral blood flow and cortical thickness on memory function in cognitively normal older adults.

OBJECTIVE: The ε4 allele of the apolipoprotein E (APOE) gene increases risk for cognitive decline in normal and pathologic aging. However, precisely how APOE ε4 exerts its negative impact on cognition is poorly understood. The present study aimed to determine whether APOE genotype (ε4+ vs. ε4-) modifies the interaction of medial temporal lobe (MTL) resting cerebral blood flow (CBF) and brain structure (cortical thickness [CT], volume [Vo]) on verbal memory performance. METHODS: Multiple linear regression models were employed to investigate relationships between APOE genotype, arterial spin labeling MRI-measured CBF and FreeSurfer-based CT and Vo in four MTL regions of interest (left and right entorhinal cortex and hippocampus), and verbal memory performance among a sample of 117 cognitively normal older adults (41 ε4+, 76 ε4-) between the ages of 64 and 89 (mean age â€‹= â€‹73). RESULTS: Results indicated that APOE genotype modified the interaction of CBF and CT on memory in the left entorhinal cortex, such that the relationship between entorhinal CBF and memory was negative (lower CBF was associated with better memory) in non-carriers with higher entorhinal CT, positive (higher CBF was associated with better memory) in non-carriers with lower entorhinal CT, and negative (higher CBF was associated with worse memory) in ε4 carriers with lower entorhinal CT. CONCLUSIONS: Findings suggest that older adult APOE ε4 carriers may experience vascular dysregulation and concomitant morphological alterations in the MTL that interact to negatively affect memory even in the absence overt clinical symptoms, providing potential insight into the mechanistic link between APOE ε4 and detriments in cognition. Moreover, findings suggest a distinct multimodal neural signature in ε4 carriers (higher CBF and lower CT in the entorhinal cortex) that could aid in the identification of candidates for future clinical trials aimed at preventing or slowing cognitive decline. Differential findings with respect to ε4 carriers and non-carriers are discussed in the context of neurovascular compensation.

Age-related changes in the dynamics of fear-related regulation in early childhood.

Self-regulation is a dynamic process wherein executive processes (EP) delay, minimize or desist prepotent responses (PR) that arise in situations that threaten well-being. It is generally assumed that, over the course of early childhood, children expand and more effectively deploy their repertoire of EP-related strategies to regulate PR. However, longitudinal tests of these assumptions are scarce in part because self-regulation has been mostly studied as a static construct. This study engages dynamic systems modeling to examine developmental changes in self-regulation between ages 2 and 5 years. Second-by-second time-series data derived from behavioral observations of 112 children (63 boys) faced with novel laboratory-based situations designed to elicit wariness, hesitation, and fear were modeled using differential equation models designed to capture age-related changes in the intrinsic dynamics and bidirectional coupling of PR (fear/wariness) and EP (strategy use). Results revealed that dynamic models allow for the conceptualization and measurement of fear regulation as intrinsic processes as well as direct and indirect coupling between PR and EP. Several patterns of age-related changes were in line with developmental theory suggesting that PR weakened and was regulated more quickly and efficiently by EP at age 5 than at age 2. However, most findings were in the intrinsic dynamics and moderating influences between PR and EP rather than direct influences. The findings illustrate the precision with which specific aspects of self-regulation can be articulated using dynamic systems models, and how such models can be used to describe the development of self-regulation in nuanced and theoretically meaningful ways.

Dorsomedial Prefrontal Activity to Sadness Predicts Later Emotion Suppression and Depression Severity in Adolescent Girls.

The present study used cross-lagged panel analyses to test longitudinal associations among emotion regulation, prefrontal cortex (PFC) function, and depression severity in adolescent girls. The ventromedial and dorsomedial PFC (vmPFC and dmPFC) were regions of interest given their roles in depression pathophysiology, self-referential processing, and emotion regulation. At ages 16 and 17, seventy-eight girls completed a neuroimaging scan to assess changes in vmPFC and dmPFC activation to sad faces, and measures of depressive symptom severity and emotion regulation. The 1-year cross-lagged effects of dmPFC activity at age 16 on expressive suppression at age 17 and depressive symptomatology at age 17 were significant, demonstrating a predictive relation between dmPFC activity and both suppression and depressive severity.

Linking autonomic physiology and emotion regulation in preschoolers: The role of reactivity and recovery.

Physiological recovery from negative emotions may be important for effective self-regulation, but little is known about recovery processes in children. The current study investigated links between autonomic physiology, anger expressions, and emotion regulation in a sample of eighty-three 3.5-year-olds. Respiratory sinus arrhythmia and pre-ejection period were measured during an anger induction task as parasympathetic and sympathetic indices, respectively. We examined whether preschoolers' anger expressions and emotion regulation behaviors were associated with individual differences in physiology. Autonomic changes were more strongly linked with emotion regulation than with expressed anger. Verbalized regulatory strategies were linked with greater sympathetic reactivity and also with greater recovery. In contrast, attention diversion was associated with blunted patterns of sympathetic reactivity followed by increased sympathetic arousal in the recovery phase. Disengaging from an emotional challenge may be linked with reduced physiological arousal in the short term, this behavior but also appears to have delayed consequences for physiological recovery.

On Measuring and Modeling Physiological Synchrony in Dyads.

Physiological synchrony within a dyad, or the degree of temporal correspondence between two individuals' physiological systems, has become a focal area of psychological research. Multiple methods have been used for measuring and modeling physiological synchrony. Each method extracts and analyzes different types of physiological synchrony, where 'type' refers to a specific manner through which two different physiological signals may correlate. Yet, to our knowledge, there is no documentation of the different methods, how each method corresponds to a specific type of synchrony, and the statistical assumptions embedded within each method. Hence, this article outlines several approaches for measuring and modeling physiological synchrony, connects each type of synchrony to a specific method, and identifies the assumptions that need to be satisfied for each method to appropriately extract each type of synchrony. Furthermore, this article demonstrates how to test for between-dyad differences of synchrony via inclusion of dyad-level (i.e., time-invariant) covariates. Finally, we complement each method with an empirical demonstration, as well as online supplemental material that contains Mplus code.

Differential susceptibility to effects of maternal sensitivity? A study of candidate plasticity genes.

Here we tested whether there was genetic moderation of effects of early maternal sensitivity on social-emotional and cognitive-linguistic development from early childhood onward and whether any detected Gene × Environment interaction effects proved consistent with differential-susceptibility or diathesis-stress models of Person × Environment interaction (N = 695). Two new approaches for evaluating models were employed with 12 candidate genes. Whereas maternal sensitivity proved to be a consistent predictor of child functioning across the primary-school years, candidate genes did not show many main effects, nor did they tend to interact with maternal sensitivity/insensitivity. These findings suggest that the developmental benefits of early sensitive mothering and the costs of insensitive mothering look more similar than different across genetically different children in the current sample. Although acknowledgement of this result is important, it is equally important that the generally null Gene × Environment results reported here not be overgeneralized to other samples, other predictors, other outcomes, and other candidate genes.

Estimating substance use disparities across intersectional social positions using machine learning: An application of group-lasso interaction network.

OBJECTIVE: An aim of quantitative intersectional research is to model the joint impact of multiple social positions on health risk behaviors. Although moderated multiple regression is frequently used to pursue intersectional research hypotheses, such parametric approaches may produce unreliable effect estimates due to data sparsity and high dimensionality. Machine learning provides viable alternatives, offering greater flexibility in evaluating many candidate interactions amid sparse data conditions, yet remains rarely employed. This study introduces group-lasso interaction network (glinternet), a novel machine learning approach involving hierarchical regularization, to assess intersectional differences in substance use prevalence. METHOD: Utilizing variable selection and parameter stabilization functionality for main and interaction effects, glinternet was employed to examine two-way interactions between three primary social positions (gender, sexual orientation, and race) predicting heavy episodic drinking, cannabis use, and cigarette use prevalence. Analyses were conducted using the All of Us Research Program (N = 283,403), a national sample with high representation from populations historically underrepresented in biomedical research. Results were replicated using holdout cross-validation and compared against logistic regression estimates. RESULTS: Glinternet prevalence estimates were more stable across discovery and replication samples relative to logistic regression, particularly among sparsely represented groups. Prevalence estimates for cigarette and cannabis use were elevated among sexual minority and White cisgender women compared to heterosexual and non-White women, respectively. CONCLUSIONS: Glinternet may improve upon traditional moderated multiple regression methods for pursuing intersectional hypotheses by improving model parsimony and parameter stability, providing novel means for quantifying health disparities among intersectional social positions. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Bilingualism and Structural Network Organization in Temporal Lobe Epilepsy: Resilience in Neurologic Disease.

BACKGROUND AND OBJECTIVES: There is growing evidence that bilingualism can induce neuroplasticity and modulate neural efficiency, resulting in greater resistance to neurologic disease. However, whether bilingualism is beneficial to neural health in the presence of epilepsy is unknown. We tested whether bilingual individuals with temporal lobe epilepsy (TLE) have improved whole-brain structural white matter network organization. METHODS: Healthy controls and individuals with TLE recruited from 2 specialized epilepsy centers completed diffusion-weighted MRI and neuropsychological testing as part of an observational cohort study. Whole-brain connectomes were generated via diffusion tractography and analyzed using graph theory. Global analyses compared network integration (path length) and specialization (transitivity) in TLE vs controls and in a 2 (left vs right TLE) × 2 (bilingual vs monolingual) model. Local analyses compared mean local efficiency of predefined frontal-executive and language (i.e., perisylvian) subnetworks. Exploratory correlations examined associations between network organization and neuropsychological performance. RESULTS: A total of 29 bilingual and 88 monolingual individuals with TLE matched on several demographic and clinical variables and 81 age-matched healthy controls were included. Globally, a significant interaction between language status and side of seizure onset revealed higher network organization in bilinguals compared with monolinguals but only in left TLE (LTLE). Locally, bilinguals with LTLE showed higher efficiency in frontal-executive but not in perisylvian networks compared with LTLE monolinguals. Improved whole-brain network organization was associated with better executive function performance in bilingual but not monolingual LTLE. DISCUSSION: Higher white matter network organization in bilingual individuals with LTLE suggests a neuromodulatory effect of bilingualism on whole-brain connectivity in epilepsy, providing evidence for neural reserve. This may reflect attenuation of or compensation for epilepsy-related dysfunction of the left hemisphere, potentially driven by increased efficiency of frontal-executive networks that mediate dual-language control. This highlights a potential role of bilingualism as a protective factor in epilepsy, motivating further research across neurologic disorders to define mechanisms and develop interventions.

White matter network organization predicts memory decline after epilepsy surgery.

The authors have withdrawn their manuscript owing to a substantial change in data analysis and findings/conclusions. Therefore, the authors do not wish this work to be cited as reference for the project. If you have any questions, please contact the corresponding author.

Preoperative white matter network organization and memory decline after epilepsy surgery.

OBJECTIVE: Risk for memory decline is a common concern for individuals with temporal lobe epilepsy (TLE) undergoing surgery. Global and local network abnormalities are well documented in TLE. However, it is less known whether network abnormalities predict postsurgical memory decline. The authors examined the role of preoperative global and local white matter network organization and risk of postoperative memory decline in TLE. METHODS: One hundred one individuals with TLE (n = 51 with left TLE and 50 with right TLE) underwent preoperative T1-weighted MRI, diffusion MRI, and neuropsychological memory testing in a prospective longitudinal study. Fifty-six age- and sex-matched controls completed the same protocol. Forty-four patients (22 with left TLE and 22 with right TLE) subsequently underwent temporal lobe surgery and postoperative memory testing. Preoperative structural connectomes were generated via diffusion tractography and analyzed using measures of global and local (i.e., medial temporal lobe [MTL]) network organization. Global metrics measured network integration and specialization. The local metric was calculated as an asymmetry of the mean local efficiency between the ipsilateral and contralateral MTLs (i.e., MTL network asymmetry). RESULTS: Higher preoperative global network integration and specialization were associated with higher preoperative verbal memory function in patients with left TLE. Higher preoperative global network integration and specialization, as well as greater leftward MTL network asymmetry, predicted greater postoperative verbal memory decline for patients with left TLE. No significant effects were observed in right TLE. Accounting for preoperative memory score and hippocampal volume asymmetry, MTL network asymmetry uniquely explained 25%-33% of the variance in verbal memory decline for left TLE and outperformed hippocampal volume asymmetry and global network metrics. MTL network asymmetry alone produced good diagnostic classification of memory decline in left TLE (i.e., an area under the receiver operating characteristic curve of 0.80-0.84 and correct classification of 65%-76% of cases with cross-validation). CONCLUSIONS: These preliminary data suggest that global white matter network disruption contributes to verbal memory impairment preoperatively and predicts postsurgical verbal memory outcomes in left TLE. However, a leftward asymmetry of MTL white matter network organization may confer the highest risk for verbal memory decline. Although this requires replication in a larger sample, the authors demonstrate the importance of characterizing preoperative local white matter network properties within the to-be-operated hemisphere and the reserve capacity of the contralateral MTL network, which may eventually be useful in presurgical planning.

Nocturnal emissions: a failure to replicate.

A time series of nocturnal emissions was presented in The American Journal of Psychology in 1904. The anonymous author of this remarkable article provided the time series to support his contention that his nocturnal emissions exhibited a seasonal pattern of variation. Specifically, he claimed to have heightened emissions during spring and summer, with dampened emissions later. The basis for this claim was a time series graph of average emissions by month across an 8-year period. The purpose of this article is to reanalyze these data with statistical procedures developed in the past century to validate the original conclusion drawn by the author. After analyses of the data with several state-of-the-art methods, no statistical support was found for a seasonal pattern of nocturnal emissions.

Adrenocortical responses of emerging adults in California in the two months following the Pulse night club massacre: Evidence for distal stress responses.

This study examined adrenocortical responses in the days following the Pulse nightclub massacre on June 12, 2016, among emerging adults in Northern California (N = 202; M = 23.18 years, SD = 2.56; 25% LGBQ-Latinx, 25% LGBQ-White, 25% Straight-Latinx, and 25% Straight-White) between June 13-August 12, 2016. As predicted, participants tested more proximally to the massacre had higher waking cortisol (intercepts) and flatter diurnal cortisol output (slopes), indicative of time-dependent adrenocortical arousal across the day. The effect of days post-massacre on waking cortisol was moderated by daily distress, with days since the Pulse massacre predicting waking cortisol significant only for participants reporting lower distress; participants who reported feeling higher daily distress had elevated waking cortisol across the testing period. These findings were independent of weekly personal stressors, and consistent across participants' demographic and identity characteristics. The violent attack at the Pulse nightclub was connected to increased waking cortisol and diurnal cortisol production for several days after the massacre, in a distal population exposed to the massacre vicariously, and especially for individuals not experiencing other, personal stressors. Heightened physiological responses to violent crimes support policy efforts to protect vulnerable communities, including violence prevention, gun control, and community-based trauma response services for those directly and indirectly affected by gun violence.

Association Between Microstructural Asymmetry of Temporal Lobe White Matter and Memory Decline After Anterior Temporal Lobectomy.

BACKGROUND AND OBJECTIVES: Risk for memory decline is a substantial concern in patients with temporal lobe epilepsy (TLE) undergoing anterior temporal lobectomy (ATL). Although prior studies have identified associations between memory and integrity of white matter (WM) networks within the medial temporal lobe (MTL) preoperatively, we contribute a study examining whether microstructural asymmetry of deep and superficial WM networks within the MTL predicts postoperative memory decline. METHODS: Patients with drug-resistant TLE were recruited from 2 epilepsy centers in a prospective longitudinal study. All patients completed preoperative T1 and diffusion-weighted MRI (DWI) as well as preoperative and postoperative neuropsychological testing. Preoperative fractional anisotropy (FA) of the WM directly beneath the neocortex (i.e., superficial WM [SWM]) and of deep WM tracts associated with memory were calculated. Asymmetry was calculated for hippocampal volume and FA of each WM tract or region and examined in linear and logistic regressions with preoperative to postoperative memory change as the primary outcome. RESULTS: Data were analyzed from 42 patients with TLE (19 left TLE [LTLE], 23 right TLE [RTLE]) who underwent ATL. Leftward FA asymmetry of the entorhinal SWM was associated with decline on prose and associative recall in LTLE, whereas leftward FA asymmetry of the uncinate fasciculus (UNC) was associated with decline on prose recall only. After controlling for preoperative memory score and hippocampal volume, leftward FA asymmetry of the entorhinal SWM uniquely contributed to decline in both prose and associative recall (ß = -0.46; SE 0.14 and ß = -0.68; SE 0.22, respectively) and leftward FA asymmetry of the UNC uniquely contributed to decline in prose recall (ß = -0.31; SE 0.14). A model combining asymmetry of hippocampal volume and entorhinal FA correctly classified memory outcomes in 79% of patients with LTLE for prose (area under the curve [AUC] 0.89; sensitivity 82%; specificity 75%) and 81% of patients for associative (AUC 0.79; sensitivity 83%; specificity 80%) recall. Entorhinal SWM asymmetry was the strongest predictor in both models. DISCUSSION: Preoperative asymmetry of deep WM and SWM integrity within the MTL is a strong predictor of postoperative memory decline in TLE, suggesting that surgical decision-making may benefit from considering each patient's WM network adequacy and reserve in addition to hippocampal integrity. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that preoperative asymmetry of deep WM and SWM integrity within the MTL is a predictor of postoperative memory decline.

Strengthening capacity for implementation of evidence-based practices for autism in schools: The roles of implementation climate, school leadership, and fidelity.

Understanding the factors that influence the use of evidence-based practices (EBPs) for autism spectrum disorder (ASD) in schools is critical to the selection of effective implementation strategies to support their sustained use. The current study has 2 aims: (a) evaluate the association between school leadership profiles (undifferentiated and optimal) and fidelity of EBP implementation and (b) examine the role of implementation climate as a mediator in this association. Participants included 56 principals, 90 special education teachers, and 133 classroom staff from 66 elementary schools. Participants completed the Multifactor Leadership Questionnaire and Implementation Climate Scale. Teachers and staff reported on intensity (frequency) of EBP delivery, and the research team rated the accuracy (adherence) to the components of the EBP. Schools were required to implement at least 1 of 3 EBPs for ASD (discrete trial training, pivotal response training, or visual supports). Using structural equation modeling, we found that schools with optimal leadership had higher observed ratings of teacher and staff fidelity for pivotal response training accuracy (p < .05), but not for discrete trial training or visual supports. However, this association became nonsignificant with the introduction of implementation climate into the models. Optimal leadership profiles were linked to more positive teacher/staff-reported implementation climate, compared with undifferentiated profiles (p < .01), but found no association between implementation climate and fidelity. Overall, the results of this study indicate that the role of principal leadership in EBP implementation is complex, which has implications for fostering a conducive organizational implementation context in schools. (PsycInfo Database Record (c) 2020 APA, all rights reserved).