to guide neuropsychiatry toward precision medicine. Its inception was partly in response to the overlap of clinical manifestations between different DSM-IV diagnoses within a category. For example, anxiety disorders comprise a DSM-IV category that includes diagnoses that differ from each other but are all characterized by dysregulated fear levels. Whether DSM-IV-based and Research Domain Criteria-based analytic approaches provide distinct or similar information with regard to the fear circuitry of individuals with anxiety disorders has not been directly tested. OBJECTIVE To use a threat conditioning and extinction protocol to conduct categorical (DSM-IV-based) and dimensional (Research Domain Criteria-based) assessments of psychophysiological, neural, and psychometric responses in individuals with and without anxiety disorders. DESIGN, SETTING, AND PARTICIPANTS This cross-sectional study was conducted at the Athinoula A. Martinos Center for Biomedical Imaging at Massachusetts General Hospital in Boston between March 2013 and May 2015. Functional magnetic resonance imaging was used to assess psychophysiological, neural, and psychometric responses among adults aged 18 to 65 years with specific phobia, generalized anxiety disorder, social anxiety disorder, and panic disorder as well as a control group of adults without anxiety disorders. Data were analyzed between May 2018 and April 2019. EXPOSURES A 2-day threat conditioning and extinction protocol.MAIN OUTCOMES AND MEASURES Skin conductance responses and blood oxygenated level-dependent responses were measured during the threat and extinction protocol. The categorical analysis was performed by grouping participants based on their primary DSM-IV diagnosis. The dimensional analysis was performed by regrouping participants, irrespective of their diagnoses, based on their skin conductance responses to shock delivery during threat conditioning. RESULTSThis cross-sectional study of 114 adults aged 18 to 65 years included 93 participants (34 men and 59 women; mean [SD] age, 29.7 [11.1] years) with at least 1 anxiety disorder (specific phobia, generalized anxiety disorder, social anxiety disorder, or panic disorder) and 21 participants (11 men and 10 women) without an anxiety disorder. The categorical DSM-IV-based approach indicated that all anxiety disorder groups exhibited hypoactivation in the ventromedial prefrontal cortex during extinction recall (η p 2 = 0.15; P = .004). The Research Domain Criteria-based approach revealed that higher arousal to the unconditioned stimulus was associated with higher threat responses during extinction recall (for skin conductance responses, η p 2 = 0.21; P = .01 and in functional magnetic resonance imaging results, η p 2 = 0.12; P = .02). The direct comparison of DSM-IV-based vs Research Domain Criteria-based results did not yield significant findings (η p 2 values ranged from 0.02 to 0.078; P values ranged from .09 to .98), suggesting no overlap between the approaches. CONCLUSIONS AND RELEVANCEThe data obtained from both approaches ...

ObjectivesTo provide a detailed and current characterisation of funding of a representative sample clinical trials. We also aimed to develop guidance for standardised reporting of funding information.MethodsWe addressed the extent to which clinical trials published in 2015 in any of the 119 Core Clinical Journals included a statement on the funding source (eg, whether a not-for-profit organisation was supported by a private-for-profit organisation), type of funding, amount and role of funder. We used a stepwise approach to develop a guidance and an instrument for standardised reporting of funding information.ResultsOf 200 trials, 178 (89%) included a funding statement, of which 171 (96%) reported being funded. Funding statements in the 171 funded trials indicated the source in 100%, amount in 1% and roles of funders in 50%. The most frequent sources were governmental (58%) and private-for-profit (40%). Of 54 funding statements in which the source was a not-for-profit organisation, we found evidence of undisclosed support of those from private-for-profit organisation(s) in 26 (48%). The most frequently reported roles of funders in the 171 funded trials related to study design (42%) and data analysis, interpretation or management (41%). Of 139 randomised controlled trials (RCTs) addressing pharmacological or surgical interventions, 29 (21%) reported information on the supplier of the medication or device. The proposed guidance addresses both the funding information that RCTs should report and the reporting process. Attached to the guidance is a fillable PDF document for use as an instrument for standardised reporting of funding information.ConclusionAlthough the majority of RCTs report funding, there is considerable variability in the reporting of funding source, amount and roles of funders. A standardised approach to reporting of funding information would address these limitations. Future research should explore the implications of funding by not-for-profit organisations that are supported by for-profit organisations.

Skin conductance response (SCR) is often used as an index of conditioned fear. SCR has been shown to be highly variable, and absence of SC reactivity is sometimes used as criteria for excluding data. It is, however, possible that low or no SC reactivity is the result of a distinct biological signature that underlies individual differences in SCR reactivity. This study examined neural correlates associated with the near absence of SCR conditionability. Archival data from 109 healthy adults aged 18–60 years were pooled. All individuals had participated in a fear conditioning protocol in a fMRI environment, during which two cues were partially reinforced (CS+) with a shock and a third cue was not (CS−). Using SCR to the conditioned stimuli and differential SCR (CS+ minus CS−), we created two groups of 30 individuals: low conditioners (defined as those showing the smallest SCR to the CS+ and smallest differential SCR) and high conditioners (defined as those showing the largest SCR to the CS+ and largest differential SCR). Our analyses showed differences in patterns of brain activations between these two groups during conditioning in the following regions: dorsal anterior cingulate cortex, amygdala, subgenual anterior cingulate cortex, and insular cortex. Our findings suggest that low or absent SCR conditionability is associated with hypoactivation of brain regions involved in fear learning and expression. This highlights the need to be cautious when excluding SCR nonconditioners and to consider the potential implications of such exclusion when interpreting the findings from studies of conditioned fear.

The ENIGMA group on Generalized Anxiety Disorder (ENIGMA-Anxiety/GAD) is part of a broader effort to investigate anxiety disorders using imaging and genetic data across multiple sites worldwide. The group is actively conducting a mega-analysis of a large number of brain structural scans. In this process, the group was confronted with many methodological challenges related to study planning and implementation, between-country transfer of subject-level data, quality control of a considerable amount of imaging data, and choices related to statistical methods and efficient use of resources. This report summarizes the background information and rationale for the various methodological decisions, as well as the approach taken to implement them. The goal is to document the approach and help guide other research groups working with large brain imaging data sets as they develop their own analytic pipelines for mega-analyses.

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