Publications by authors named "J P A Ioannidis"

The level of correlation between two phenomena is limited by the accuracy at which these phenomena are measured. Despite numerous group reliability studies, the strength of the fMRI connectivity that can be detected given the within-subject time course reliability remains elusive. Moreover, it is unclear how within-subject time course reliability limits the robust detection of connectivity on the group level.

View Article and Find Full Text PDF

Research funding systems fundamentally influence how science operates. This paper aims to analyze the allocation of competitive research funding from different perspectives: How reliable are decision processes for funding? What are the economic costs of competitive funding? How does competition for funds affect doing risky research? How do competitive funding environments affect scientists themselves, and which ethical issues must be considered? We attempt to identify gaps in our knowledge of research funding systems; we propose recommendations for policymakers and funding agencies, including empirical experiments of decision processes and the collection of data on these processes. With our recommendations, we hope to contribute to developing improved ways of organizing research funding.

View Article and Find Full Text PDF

Umbrella reviews are systematic reviews of all systematic reviews on a given question and can provide a higher-level view of current available evidence on broad research topics. Given the importance and possible consequences of the insights derived from umbrella reviews, it is fundamental to ensure accurate, comprehensive reporting and methodological rigor in these papers. Here, we present the potential and limitations of these evolving evidence synthesis tools by looking at umbrella reviews published on vaccine research.

View Article and Find Full Text PDF
Article Synopsis
  • The study investigates how using small datasets to select an optimal cutoff score for the Patient Health Questionnaire-9 (PHQ-9) can lead to inaccurate results.
  • Researchers evaluated whether data-driven methods for cutoff selection resulted in scores that were significantly different from the true population optimal score and if these methods produced biased accuracy estimates.
  • Findings showed that many small studies frequently failed to identify the correct optimal cutoff score, particularly in smaller samples, leading to an overestimation of test sensitivity.
View Article and Find Full Text PDF

Healthcare workers may have different risk for severe outcomes compared with the general population during diverse crises. This paper introduces the concept of healthcare worker versus population hazard (HPH), the risk of an outcome of interest in active healthcare workers compared with the general population they serve. HPH can be expressed with relative risk (HPH(r)) and absolute risk difference (HPH(a)) metrics.

View Article and Find Full Text PDF

A PHP Error was encountered

Severity: Warning

Message: A non-numeric value encountered

Filename: controllers/Author.php

Line Number: 219

Backtrace:

File: /var/www/html/application/controllers/Author.php
Line: 219
Function: _error_handler

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: A non-numeric value encountered

Filename: libraries/Pagination.php

Line Number: 413

Backtrace:

File: /var/www/html/application/controllers/Author.php
Line: 274
Function: create_links

File: /var/www/html/index.php
Line: 316
Function: require_once