Patient safety has recently become one of the most prominent issues in health policy, as increased evidence of a high rate of errors during the delivery of medical care has begun to undermine the trust that patients and policy makers have historically bestowed on the medical profession. As early as 1991, the landmark Harvard Medical Practice Study found that adverse events occur in 1 to 4% of all hospital admissions (Brennan et al., 1991). The US Institute of Medicine integrated the available evidence on medical errors and estimated that more people die from medical errors than from traffic injuries or breast cancer (Kohn et al., 2000). One recent Swedish study showed that over 12% of hospital admissions had adverse events, of which 70% were preventable, resulting in an increased length of stay of 6 days (Soop et al., 2009). The Council of the European Union adopted in 2009 a Recommendation on patient safety, including the prevention and control of healthcare associated infections (European Union, 2009).