Evaluation of interventions to prevent vasovagal reactions among whole blood donors: rationale and design of a large cluster randomised trial.

Background: Vasovagal reactions (VVRs) are the most common acute complications of blood donation. Responsible for substantial morbidity, they also reduce the likelihood of repeated donations and are disruptive and costly for blood services. Although blood establishments worldwide have adopted different strategies to prevent VVRs (including water loading and applied muscle tension [AMT]), robust evidence is limited.

Healthy snacks in hospitals: Testing the potential effects of changes in availability.

Background: Hospitals offer snacks for sale to patients, staff and visitors.

Aim: As food choice is heavily influenced by the options available, the present study (a) audited snack availability and purchase in NHS hospital sites across a large UK city; and (b) tested the potential effects of changes to this availability in an online choice experiment.

Methods: In Study 1 (audit), single-serve snacks (=376) available in 76 hospital food retail units were audited.