Personality influences responses to inequity and contrast in chimpanzees.

Several species besides humans respond negatively to inequity (i.e. receiving a less preferred outcome as compared to a social partner).

Effective messages in vaccine promotion: a randomized trial.

Objectives: To test the effectiveness of messages designed to reduce vaccine misperceptions and increase vaccination rates for measles-mumps-rubella (MMR).

Methods: A Web-based nationally representative 2-wave survey experiment was conducted with 1759 parents age 18 years and older residing in the United States who have children in their household age 17 years or younger (conducted June-July 2011). Parents were randomly assigned to receive 1 of 4 interventions: (1) information explaining the lack of evidence that MMR causes autism from the Centers for Disease Control and Prevention; (2) textual information about the dangers of the diseases prevented by MMR from the Vaccine Information Statement; (3) images of children who have diseases prevented by the MMR vaccine; (4) a dramatic narrative about an infant who almost died of measles from a Centers for Disease Control and Prevention fact sheet; or to a control group.

The role of social networks in influenza vaccine attitudes and intentions among college students in the Southeastern United States.

Purpose: To investigate whether support for vaccines among one's health discussants is associated with beliefs in vaccine safety and intention to vaccinate among college students.

Methods: Ordered logistic regression analysis was conducted of data collected from 1,019 undergraduates at a large public university in 2009 and 2010.

Results: Having health discussion networks that support vaccination is a significant predictor of beliefs of H1N1 vaccine safety (adjusted odds ratio [aOR] = 2.