摘要：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. Results . Among those who received a first dose of varicella (n = 16 075), hepatitis A (n = 594 917), and hepatitis B (n = 590 445) vaccine, relatively few completed the series (55%–65% for hepatitis B vaccine and 40%–50% for hepatitis A and varicella vaccines in most age groups). Compliance was lowest among adolescents (35.9%) and Medicaid recipients (29.7%) who received varicella vaccine and among younger adult age groups who received hepatitis A vaccine (25%–35% across those age groups). Even among series completers, there was a relatively long interval of undervaccination between the first and last doses. Conclusions. Compliance with multiple-dose vaccine series among older children, adolescents, and adults is suboptimal. Further evaluations of strategies to improve compliance in these populations are needed. Many vaccines given to older children, adolescents, and adults require multiple doses for optimal immunogenicity and efficacy. Varicella vaccine is recommended in a 2-dose series for children 13 years or older without evidence of immunity. 1 The hepatitis A 2 and B 3 , 4 vaccine series require 2 and 3 doses, respectively. Most recently, in 2007, vaccination with the 3-dose human papillomavirus vaccine series was recommended for adolescent and young adult women. 5 Timely and complete vaccination with multiple-dose schedules is of public health importance, because an incomplete series may yield suboptimal disease protection. 6 – 17 Comprehensive monitoring is conducted annually to evaluate compliance with vaccination schedules among infants and young children. 18 However, there is little information on compliance with multiple-dose vaccine series in general populations of older children, adolescents, and adults. 19 – 21 We conducted a large, population-based, retrospective cohort study of older children, adolescents, and adults in the Vaccine Safety Datalink population of approximately 8.8 million Medical Care Organization (MCO) enrollees, which represents about 3% of the US population. During the study period (1996–2004), we determined compliance with the 2- or 3-dose varicella, hepatitis A, or hepatitis B vaccine series in this population. We also assessed factors associated with noncompliance, and among those who completed the vaccination series, we examined the timeliness of completion to determine the excess duration of time that individuals remained undervaccinated.
