Compliance with multiple-dose vaccine schedules among older children, adolescents, and adults: results from a vaccine safety datalink study.

Objectives: We studied compliance with multiple-dose vaccine schedules, assessed factors associated with noncompliance, and examined timeliness of series completion among older children, adolescents, and adults.

Methods: We conducted a large, multisite, retrospective cohort study of older children, adolescents, and adults in the Vaccine Safety Datalink population from 1996 through 2004. We quantified the rates of completion of all required doses for varicella, hepatitis A, and hepatitis B vaccines according to their recommended schedules.

Impact of the introduction of pneumococcal conjugate vaccine on rates of community acquired pneumonia in children and adults.

Pneumococcal conjugate vaccine use among young children has led to significant declines in invasive pneumococcal disease in the United States, but the impact on community-acquired pneumonia is unknown. We conducted population-based pneumonia surveillance among 794,282 Group Health members before and after infant vaccine introduction in 2000. We presumptively identified pneumonia episodes using diagnosis codes assigned to medical encounters and confirmed 17,513 outpatient and 6318 hospitalized events by reviewing chest radiograph reports or hospitalization records.