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This report provides practical recommendations for the design and execution of Multi-Center functional Magnetic Resonance Imaging (MC-fMRI) studies based on the collective experience of the Function Biomedical Informatics Research Network (FBIRN). The paper was inspired by many requests from the fMRI community to FBIRN group members for advice on how to conduct MC-fMRI studies. The introduction briefly discusses the advantages and complexities of MC-fMRI studies. Prerequisites for MC-fMRI studies are addressed before delving into the practical aspects of carefully and efficiently setting up a MC-fMRI study. Practical multi-site aspects include: (1) establishing and verifying scan parameters including scanner types and magnetic fields, (2) establishing and monitoring of a scanner quality program, (3) developing task paradigms and scan session documentation, (4) establishing clinical and scanner training to ensure consistency over time, (5) developing means for uploading, storing, and monitoring of imaging and other data, (6) the use of a traveling fMRI expert and (7) collectively analyzing imaging data and disseminating results. We conclude that when MC-fMRI studies are organized well with careful attention to unification of hardware, software and procedural aspects, the process can be a highly effective means for accessing a desired participant demographics while accelerating scientific discovery.

Due to the increasing need for subject privacy, the ability to deidentify structural MR images so that they do not provide full facial detail is desirable. A program was developed that uses models of nonbrain structures for removing potentially identifying facial features. When a novel image is presented, the optimal linear transform is computed for the input volume (Fischl et al. [2002]: Neuron 33:341-355; Fischl et al. [2004]: Neuroimage 23 (Suppl 1):S69-S84). A brain mask is constructed by forming the union of all voxels with nonzero probability of being brain and then morphologically dilated. All voxels outside the mask with a nonzero probability of being a facial feature are set to 0. The algorithm was applied to 342 datasets that included two different T1-weighted pulse sequences and four different diagnoses (depressed, Alzheimer's, and elderly and young control groups). Visual inspection showed none had brain tissue removed. In a detailed analysis of the impact of defacing on skull-stripping, 16 datasets were bias corrected with N3 (Sled et al. [1998]: IEEE Trans Med Imaging 17:87-97), defaced, and then skull-stripped using either a hybrid watershed algorithm (Ségonne et al. [2004]: Neuroimage 22:1060-1075, in FreeSurfer) or Brain Surface Extractor (Sandor and Leahy [1997]: IEEE Trans Med Imaging 16:41-54; Shattuck et al. [2001]: Neuroimage 13:856-876); defacing did not appreciably influence the outcome of skull-stripping. Results suggested that the automatic defacing algorithm is robust, efficiently removes nonbrain tissue, and does not unduly influence the outcome of the processing methods utilized; in some cases, skull-stripping was improved. Analyses support this algorithm as a viable method to allow data sharing with minimal data alteration within large-scale multisite projects.

Performance of automated methods to isolate brain from nonbrain tissues in magnetic resonance (MR) structural images may be influenced by MR signal inhomogeneities, type of MR image set, regional anatomy, and age and diagnosis of subjects studied. The present study compared the performance of four methods: Brain Extraction Tool (BET; Smith [2002]: Hum Brain Mapp 17:143-155); 3dIntracranial (Ward [1999] Milwaukee: Biophysics Research Institute, Medical College of Wisconsin; in AFNI); a Hybrid Watershed algorithm (HWA, Segonne et al. [2004] Neuroimage 22:1060-1075; in FreeSurfer); and Brain Surface Extractor (BSE, Sandor and Leahy [1997] IEEE Trans Med Imag 16:41-54; Shattuck et al. [2001] Neuroimage 13:856-876) to manually stripped images. The methods were applied to uncorrected and bias-corrected datasets; Legacy and Contemporary T-1-weighted image sets; and four diagnostic groups (depressed, Alzheimer's, young and elderly control). To provide a criterion for outcome assessment, two experts manually stripped six sagittal sections for each dataset in locations where brain and nonbrain tissue are difficult to distinguish. Methods were compared on Jaccard similarity coefficients, Hausdorff distances, and an Expectation-Maximization algorithm. Methods tended to perform better on contemporary datasets; bias correction did not significantly improve method performance. Mesial sections were most difficult for all methods. Although AD image sets were most difficult to strip, HWA and BSE were more robust across diagnostic groups compared with 3dIntracranial and BET. With respect to specificity, BSE tended to perform best across all groups, whereas HWA was more sensitive than other methods. The results of this study may direct users towards a method appropriate to their T-1-weighted datasets and improve the efficiency of processing for large, multisite neuroimaging studies.

Alcohol and marijuana use are prevalent in adolescence, yet the neural impact of concomitant use remains unclear. We previously demonstrated functional magnetic resonance imaging (fMRI) response to spatial working memory (SWM) among teens with alcohol use disorders (AUD) compared to controls, and predicted that adolescents with marijuana aid alcohol use disorders would show additional abnormalities. Participants were three groups of 15-17-year-olds: 19 non-abusing controls, 15 AUD teens with limited exposure to drugs, and 15 teens with comorbid marijuana and alcohol use disorders (MAUD) and minimal other drug experience. After > 2 days' abstinence, participants performed a SWM task during fMRI acquisition. fMRI brain response patterns differed between groups, despite similar performance on the task. MAUD youths showed less activation in inferior frontal and temporal regions than controls, and more response in other prefrontal regions. Compared to AUD teens, MAUD youths also showed less inferior frontal and temporal activation, but more medial frontal response. Overall, MAUD youths showed different brain response abnormalities than teens with AUD alone, despite relatively short histories of substance involvement. This pattern could suggest compensation for marijuana-related attention and working memory deficits. However, relatively recent use and premorbid features may influence results, and should be examined in future studies. (c) 2005 Elsevier Ireland Ltd. All rights reserved.

Background: Previous studies have suggested neural disruption and reorganization in young and older adults with alcohol use disorders (AUD). However, it remains unclear at what age and when in the progression of AUD changes in brain functioning might occur. Methods: Alcohol use disordered (n = 15) and nonabusing (n = 19) boys and girls aged 15 to 17 were recruited from local high schools. Functional magnetic resonance imaging data were collected after a minimum of 5 days' abstinence as participants performed spatial working memory and simple motor tasks. Results: Adolescents with AUD showed greater brain response to the spatial working memory task in bilateral parietal cortices and diminished response in other regions, including the left precentral gyros and bilateral cerebellar areas (clusters 943 mul; p < 0.05), although groups did not differ on behavioral measures of task performance. No brain response differences were observed during a simple finger-tapping task. The degree of abnormality was greater for teens who reported experiencing more withdrawal or hangover symptoms and who consumed more alcohol. Conclusions: Adolescents with AUD show abnormalities in brain response to a spatial working memory task, despite adequate performance, suggesting that subtle neuronal reorganization may occur early in the course of AUD.

Review quizzes can provide students with feedback and assist in the preparation for in-class tests, but students often do not voluntarily use self-testing resources. The purpose of the present study was to evaluate if taking a mandatory online review quiz alters performance on subsequent in-class tests. During two semesters of a single-semester introductory anatomy and physiology course, students were required to complete brief online quizzes after each textbook chapter had been covered during lecture as well as the day before an in-class test. During the next two semesters, students were not required to take the online review quizzes. Overall scores on chapter specific in-class tests were higher (P < 0.05) during the semesters in which students took online review quizzes (82.9 ± 14.3%) compared with when they did not (78.7 ± 15.5%), but all in-class tests were not improved. Scores on comprehensive midterm examinations were higher (83.0 ± 12.9% vs. 78.9 ± 13.7%, P < 0.05) but not on final examinations (72.4 ± 13.8% vs. 71.8 ± 14.0%) between those with online review quizzes and those without, respectively. Overall scores on in-class tests and comprehensive examinations were higher (P < 0.05) during the semesters in which students took online review quizzes (83.4 ± 16.8%) compared with when they did not (80.3 ± 17.6%). These data suggest that an online review quiz taken the day before an in-class test increases performance on some in-class tests. However, online review quizzes taken after completion of each chapter do not consistently enhance performance on comprehensive examinations.

The emergence of new diseases in wildlife substantially threatens global biodiversity in many taxa (7), but amphibians face unusually high risk for pathogen-mediated population declines (2,3). Disease outbreaks among invasive [...]

Key Points: Question: Can a process improvement package in the emergency department targeting suicide prevention using evidence-based practices reduce subsequent suicidal behaviors among patients at risk of suicide? Findings: In this randomized clinical trial including 2761 patients, after a 12-month implementation period, using an interrupted time series model, a significant decrease in incidence of suicidal attempts, ideation, and behavior was observed across the 3 phases of the study (baseline, implementation, and maintenance). Meaning: Department-wide interventions aiming to improve clinic workflow can reduce likelihood of suicide, suicidal ideation, and suicide-related behaviors in the 12 months following the patient's initial ED visit. This randomized clinical trial determines if an emergency department process improvement package, with a subfocus on improving the implementation of collaborative safety planning, reduces subsequent suicide-related behaviors. Importance: Suicide is a leading cause of deaths in the US. Although the emergency department (ED) is an opportune setting, ED-initiated interventions remain underdeveloped and understudied. Objective: To determine if an ED process improvement package, with a subfocus on improving the implementation of collaborative safety planning, reduces subsequent suicide-related behaviors. Design, Setting, and Participants: The Emergency Department Safety Assessment and Follow-up Evaluation 2 (ED-SAFE 2) trial, a stepped-wedge cluster randomized clinical trial conducted in 8 EDs across the US, used an interrupted time series design with three 12-month sequential phases: baseline, implementation, and maintenance. A random sample of 25 patients per month per site 18 years and older who screened positive on the Patient Safety Screener, a validated suicide risk screener, were included. The primary analyses focused on those who were discharged from the ED, while secondary analyses focused on all patients who screened positive, regardless of disposition. Data were collected on patients who presented for care from January 2014 to April 2018, and data were analyzed from April to December 2022. Interventions: Each site received lean training and built a continuous quality improvement (CQI) team to evaluate the current suicide-related workflow in the ED, identify areas of improvement, and implement efforts to improve. Each site was expected to increase their universal suicide risk screening and implement collaborative safety planning for patients at risk of suicide who were discharged home from the ED. Site teams were centrally coached by engineers experienced in lean CQI and suicide prevention specialists. Main Outcomes and Measures: The primary outcome was a composite comprising death by suicide or suicide-related acute health care visits, measured over a 6-month follow-up window. Results: Across 3 phases, 2761 patient encounters were included in the analyses. Of these, 1391 (50.4%) were male, and the mean (SD) age was 37.4 (14.5) years. A total of 546 patients (19.8%) exhibited the suicide composite during the 6-month follow-up (9 [0.3%] died by suicide and 538 [19.5%] of a suicide-related acute health care visit). A significant difference was observed for the suicide composite outcome between the 3 phases (baseline, 216 of 1030 [21%]; implementation, 213 of 967 [22%]; maintenance, 117 of 764 [15.3%]; P =.001). The adjusted odds ratios of risk of the suicide composite during the maintenance phase was 0.57 (95% CI, 0.43-0.74) compared with baseline and 0.61 (0.46-0.79) compared with the implementation phase, which reflect a 43% and 39% reduction, respectively. Conclusions and Relevance: In this multisite randomized clinical trial, using CQI methods to implement a department-wide change in suicide-related practices, including the implementation of a safety plan intervention, yielded a significant decrease in suicide behaviors in the maintenance period of the study. Trial Registration: ClinicalTrials.gov Identifier: NCT02453243 [ABSTRACT FROM AUTHOR]