For the purposes of the database, studies are classified as education services to health care professionals if they describe education services provided by pharmacists to physicians or other health care professionals. Studies which describe educational outreach visiting or “detailing” (with or without the provision of additional materials such as prescribing guidelines, promotional leaflets, mailed education campaigns) are included if the face-to-face visiting is conducted by a pharmacist. Studies that describe outreach visiting conducted by a multidisciplinary team or a physician and a pharmacist are excluded. Studies are also excluded if it is unclear whether a pharmacist conducted the educational visit.