15 research outputs found

    Variability in the analysis of a single neuroimaging dataset by many teams

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    Data analysis workflows in many scientific domains have become increasingly complex and flexible. To assess the impact of this flexibility on functional magnetic resonance imaging (fMRI) results, the same dataset was independently analyzed by 70 teams, testing nine ex-ante hypotheses. The flexibility of analytic approaches is exemplified by the fact that no two teams chose identical workflows to analyze the data. This flexibility resulted in sizeable variation in hypothesis test results, even for teams whose statistical maps were highly correlated at intermediate stages of their analysis pipeline. Variation in reported results was related to several aspects of analysis methodology. Importantly, meta-analytic approaches that aggregated information across teams yielded significant consensus in activated regions across teams. Furthermore, prediction markets of researchers in the field revealed an overestimation of the likelihood of significant findings, even by researchers with direct knowledge of the dataset. Our findings show that analytic flexibility can have substantial effects on scientific conclusions, and demonstrate factors related to variability in fMRI. The results emphasize the importance of validating and sharing complex analysis workflows, and demonstrate the need for multiple analyses of the same data. Potential approaches to mitigate issues related to analytical variability are discussed

    Variability in the analysis of a single neuroimaging dataset by many teams

    Get PDF
    Data analysis workflows in many scientific domains have become increasingly complex and flexible. To assess the impact of this flexibility on functional magnetic resonance imaging (fMRI) results, the same dataset was independently analyzed by 70 teams, testing nine ex-ante hypotheses. The flexibility of analytic approaches is exemplified by the fact that no two teams chose identical workflows to analyze the data. This flexibility resulted in sizeable variation in hypothesis test results, even for teams whose statistical maps were highly correlated at intermediate stages of their analysis pipeline. Variation in reported results was related to several aspects of analysis methodology. Importantly, meta-analytic approaches that aggregated information across teams yielded significant consensus in activated regions across teams. Furthermore, prediction markets of researchers in the field revealed an overestimation of the likelihood of significant findings, even by researchers with direct knowledge of the dataset. Our findings show that analytic flexibility can have substantial effects on scientific conclusions, and demonstrate factors related to variability in fMRI. The results emphasize the importance of validating and sharing complex analysis workflows, and demonstrate the need for multiple analyses of the same data. Potential approaches to mitigate issues related to analytical variability are discussed

    Computer Versus Paper-Based Testing: Are They Equivalent When it Comes to Working Memory?

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    School systems across the country are transitioning from paper-based testing (PBT) to computer-based testing (CBT). As this technological shift occurs, more research is necessary to understand the practical and performance implications of administering CBTs. Currently, there is a paucity of research using CBTs to examine working memory (WM) performance, even though CBTs may negatively influence performance. The present study compared a WM CBT and PBT and found enhanced WM performance on the PBT across several verbal and visuospatial WM tests. This pattern was evident even after age was controlled, indicating that test mode effects were persistent across ages (4-11 years). CBTs on WM performance may yield lower scores due to developmental WM differences, increased cognitive workload, test mode effects stemming from individual access to technology, and participant characteristics, such as developmental, biological, or gender differences. The presence of divergent WM in CBT and PBT indicates the need for additional options for children at risk of academic failure because of testing modality

    Review of the biology and vector capability of Thrips tabaci Lindeman (Thysanoptera: Thripidae)

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    Thoracic Manifestations of Systemic Diseases

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    Accidental hypothermia–an update

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