A few days ago we had a full moon. A lengthy discussion about the effect of a full moon on hospital admissions took place on Twitter.
Many papers say admissions increase and odd things happen, and many others have found there is no relationship between the phases of the moon and anything that goes on in hospitals.
Someone sent me a link to a paper that a lot of devotees of astrology like to quote. It's called "The influence of the full moon on the number of admissions related to gastrointestinal bleeding," and it appeared in the International Journal of Nursing Practice in 2004.