FIGURE 1—

Assignment of long-term care facilities (LTCFs) to intervention groups: Southern California, 2002–2003

Note. Three local health departments were unable to provide the influenza vaccine to health care workers; LTCFs in these jurisdictions were randomly assigned to the control group and the educational campaign group only. LTCFs in the fourth local health department jurisdiction were randomly assigned to the Vaccine Day group and the combined intervention (conducting both the educational campaign and the Vaccine Day interventions) group.

^aLTCFs were not eligible if they participated in the knowledge, attitudes, and behaviors survey or in an LTCF influenza vaccine survey conducted in 2001 or if they were not exclusively classified as a skilled nursing facility.