Four Failures of Deliberating Groups

Many groups make their decisions through some process of deliberation, usually with the belief that deliberation will improve judgments and predictions. But deliberating groups often fail, in the sense that they make judgments that are false or that fail to take advantage of the information that their members have. There are four such failures. (1) Sometimes the predeliberation errors of group members are amplified, not merely propagated, as a result of deliberation. (2) Groups may fall victim to cascade effects, as the judgments of initial speakers or actors are followed by their successors, who do not disclose what they know. Nondisclosure, on the part of those successors, may be a product of either informational or reputational cascades. (3) As a result of group polarization, groups often end up in a more extreme position in line with their predeliberation tendencies. Sometimes group polarization leads in desirable directions, but there is no assurance to this effect. (4) In deliberating groups, shared information often dominates or crowds out unshared information, ensuring that groups do not learn what their members know. All four errors can be explained by reference to informational signals, reputational pressure, or both. A disturbing result is that many deliberating groups do not improve on, and sometimes do worse than, the predeliberation judgments of their average or median member

A Benign, Mature, Parapharyngeal Teratoma Presenting in an Adult

We present a case of an adult female who presented mildly symptomatic and with a history of having a mass removed from her neck as an infant. Radiographic imaging detected the presence of a heterogeneous, encapsulated mass in the parapharyngeal space that was surgically resected, and subsequently pathologically confirmed to be a benign, mature cystic teratom

Describing the Prevalence of Neural Tube Defects Worldwide: A Systematic Literature Review

<div><p>Background</p><p>Folate-sensitive neural tube defects (NTDs) are an important, preventable cause of morbidity and mortality worldwide. There is a need to describe the current global burden of NTDs and identify gaps in available NTD data.</p><p>Methods and Findings</p><p>We conducted a systematic review and searched multiple databases for NTD prevalence estimates and abstracted data from peer-reviewed literature, birth defects surveillance registries, and reports published between January 1990 and July 2014 that had greater than 5,000 births and were not solely based on mortality data. We classified countries according to World Health Organization (WHO) regions and World Bank income classifications. The initial search yielded 11,614 results; after systematic review we identified 160 full text manuscripts and reports that met the inclusion criteria. Data came from 75 countries. Coverage by WHO region varied in completeness (i.e., % of countries reporting) as follows: African (17%), Eastern Mediterranean (57%), European (49%), Americas (43%), South-East Asian (36%), and Western Pacific (33%). The reported NTD prevalence ranges and medians for each region were: African (5.2–75.4; 11.7 per 10,000 births), Eastern Mediterranean (2.1–124.1; 21.9 per 10,000 births), European (1.3–35.9; 9.0 per 10,000 births), Americas (3.3–27.9; 11.5 per 10,000 births), South-East Asian (1.9–66.2; 15.8 per 10,000 births), and Western Pacific (0.3–199.4; 6.9 per 10,000 births). The presence of a registry or surveillance system for NTDs increased with country income level: low income (0%), lower-middle income (25%), upper-middle income (70%), and high income (91%).</p><p>Conclusions</p><p>Many WHO member states (120/194) did not have any data on NTD prevalence. Where data are collected, prevalence estimates vary widely. These findings highlight the need for greater NTD surveillance efforts, especially in lower-income countries. NTDs are an important public health problem that can be prevented with folic acid supplementation and fortification of staple foods.</p></div

Average Study Risk-of-Bias by World Health Organization Region.

<p>Average Study Risk-of-Bias by World Health Organization Region.</p

Prevalence per 10,000 Births for Specific Types of Neural Tube Defects by World Bank Income Classifications [18].

<p>Bars Indicate the Median Prevalence for Each Condition.</p

Average Study Risk-of-Bias by World Bank Income Classification [18].

<p>Average Study Risk-of-Bias by World Bank Income Classification [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0151586#pone.0151586.ref018" target="_blank">18</a>].</p

African Region Neural Tube Defects Prevalence Estimates (Location, Number of Hospitals).

<p>If there were national data available for more than one NTD, the entire country was filled-in based on the prevalence per 10,000 births. In instances where multiple prevalence estimates were available at the national level, the prevalence reported by the study/report with the least risk-of-bias was selected. Countries colored in grey are not a part of the World Health Organization region. Shapefile reprinted from <a href="http://www.diva-gis.org" target="_blank">http://www.diva-gis.org</a> under a CC BY license, with permission from DIVA-GIS and Dr. Robert Hijmans.</p

Percent of all Neural Tube Defects (NTDs) Attributable to Each Condition for Studies that Reported all Three Types of NTDs: Anencephaly, Spina Bifida, and Encephalocele.

<p>Bars Indicate the Median Percent for Each Condition.</p

South-East Asian Region Neural Tube Defects Prevalence Estimates (Location, Number of Hospitals).

<p>If there were national data available for more than one NTD, the entire country was filled-in based on the prevalence per 10,000 births. In instances where multiple prevalence estimates were available at the national level, the prevalence reported by the study/report with the least risk-of-bias was selected. North Korea had no reported data and was not shown in map due to scaling considerations. Shapefile reprinted from <a href="http://www.diva-gis.org" target="_blank">http://www.diva-gis.org</a> under a CC BY license, with permission from DIVA-GIS and Dr. Robert Hijmans.</p