Implementation of universal influenza immunization recommendations for healthy young children: Results of a randomized, controlled trial with registry-based recall

Department of Pediatrics, University of Colorado, Denver, Colorado, United States
PEDIATRICS (Impact Factor: 5.3). 01/2005; 115(1):146-54. DOI: 10.1542/peds.2004-1804
Source: PubMed

ABSTRACT An Advisory Committee on Immunization Practices policy of encouraging influenza vaccination for healthy 6- to 23-month-old children was in effect during the 2003-2004 influenza season, which was unusually severe in Colorado. We collaborated with 5 pediatric practices to attempt universal influenza immunization in this age group.
The objectives were (1) to assess the maximal influenza immunization rates that could be achieved for healthy young children in private practice settings, (2) to evaluate the efficacy of registry-based reminder/recall for influenza vaccination, and (3) to describe methods used by private practices to implement the recommendations.
The study was conducted in 5 private pediatric practices in Denver, Colorado, with a common billing system and immunization registry. Although recommendations by the Advisory Committee on Immunization Practices included children who were 6 to 23 months of age at any point during the influenza season, our practices chose not to recall children 22 to 23 months of age, because they would have become >24 months of age during the study period. Therefore, our study population consisted of all healthy children 6 to 21 months of age from the 5 practices (N = 5193), who were randomized to intervention groups (n = 2595) that received up to 3 reminder/recall letters or to control groups (n = 2598) that received usual care. The primary outcome was receipt of >or=1 influenza immunization, as noted either in the immunization registry or in billing data.
Immunization rates for >or=1 dose of influenza vaccine for the intervention groups in the 5 practices were 75.9%, 75.4%, 68.1%, 55.6%, and 44.3% at the end of the season. Overall, 62.4% of children in the intervention groups and 58.0% of children in the control groups were immunized (4.4% absolute difference), with absolute differences, compared with control values, ranging from 1.0% to 9.1% according to practice. However, before intensive media coverage of the influenza outbreak began (November 15, 2003), absolute differences, compared with control values, ranged from 5.1% to 15.3% and were 9.6% overall. Before November 15, significant effects of recall were seen for children in the intervention groups, in both the 12- to 21-month age category (10.4% increase over control) and the 6- to 11-month category (8.1% increase over control); at the end of the season, however, significant effects of recall were seen only for the older age group (6.2% increase over control). The rates of receipt of 2 vaccine doses >or=1 month apart for eligible children ranged from 21% to 48% among the practices. Four of the 5 practices held influenza immunization clinics during office hours, evenings, or weekends, and these clinics achieved higher coverage rates.
These results demonstrated that, in an epidemic influenza year, private practices were able to immunize the majority of 6- to 21-month-old children in a timely manner. Although media coverage regarding the epidemic blunted the effect of registry-based recall, recall was effective in increasing rates early in the epidemic, especially for children between 1 and 2 years of age. The practices that achieved the highest immunization rates were proactive in planning influenza clinics to handle the extra volume of immunizations required.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Population-based electronic immunization registries create the possibility of using registry data to conduct vaccine effectiveness studies which could have methodological advantages over traditional observational studies. For study validity, the base population would have to be clearly defined and the immunization status of members of the population accurately recorded in the registry. We evaluated a city-wide immunization registry, focusing on its potential as a tool to study pertussis vaccine effectiveness, especially in adolescents. We conducted two evaluations - one in sites that were active registry participants and one in sites that had implemented an electronic medical record with plans for future direct data transfer to the registry - of the ability to match patients' medical records to registry records and the accuracy of immunization records in the registry. For each site, records from current pediatric patients were chosen randomly. Data regarding pertussis-related immunizations, clinic usage, and demographic and identifying information were recorded; for 11-17-year-old subjects, information on MMR, hepatitis B, and varicella immunizations was also collected. Records were then matched, when possible, to registry records. For records with a registry match, immunization data were compared. Among 350 subjects from sites that were current registry users, 307 (87.7%) matched a registry record. Discrepancies in pertussis-related data were common for up-to-date status (22.6%), number of immunizations (34.7%), dates (10.2%), and formulation (34.4%). Among 442 subjects from sites that planned direct electronic transfer of immunization data to the registry, 393 (88.9%) would have matched a registry record; discrepancies occurred frequently in number of immunizations (11.9%), formulation (29.1%), manufacturer (94.4%), and lot number (95.1%.) Inability to match and immunization discrepancies were both more common in subjects who were older at their first visit to the provider site. For 11-17-year-old subjects, discrepancies were also common for MMR, hepatitis B, and varicella vaccination data. Provider records frequently could not be matched to registry records or had discrepancies in key immunization data. These issues were more common for older children and were present even with electronic data transfer. These results highlight general challenges that may face investigators wishing to use registry-based immunization data for vaccine effectiveness studies, especially in adolescents.
    BMC Public Health 02/2008; 8:160. DOI:10.1186/1471-2458-8-160 · 2.32 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A metastable olivine wedge (MOW) is detected in the subducting Pacific slab under the Japan Sea by applying a forward-modeling approach with 3-D ray tracing to high-quality arrival-time data from 78 well-located deep earthquakes. The data were recorded by the dense and high-quality seismic networks on the Japan Islands. The double-difference earthquake location technique is improved and used to relocate the 78 deep earthquakes precisely. Our results show that the MOW does exist in the Pacific slab and it has a P-wave velocity 3% lower than the normal mantle or 4% lower than the surrounding slab velocity. The top and bottom depths of the MOW are 400 and 570km, respectively, and the MOW is located in the central portion of the slab. After precise relocation, all the 78 deep earthquakes are found to occur within the MOW or along its edges within the slab. The cut-off depth of deep seismicity under the Japan Sea is consistent with the estimated MOW bottom depth. Our results favor the transformational faulting as the mechanism of deep earthquakes in the Pacific slab under the Japan Sea.
    Journal of Asian Earth Sciences 11/2011; 42:1411-1423. DOI:10.1016/j.jseaes.2011.08.005 · 2.83 Impact Factor
  • Clinical Pediatrics 03/2014; 53(10). DOI:10.1177/0009922814527505 · 1.26 Impact Factor