How should immunization rates be measured in the office setting? A study from PROS and NMA PedsNet.

The aim of the study was to compare the validity and reliability of 2 sampling methods for measuring immunization rates to a reference standard in a national sample of pediatric office practices. The consecutive method involved patients seen consecutively in the office for any reason; the random record was a random selection of medical records; and the reference standard active method, data of a randomly selected subgroup of children in the random record survey were supplemented with information from a telephone interview. The consecutive method of assessing immunization rates results in rates that are, on average, higher and closer to the reference standard, but also more variable. The random record method rates are lower and further from the study reference standard compared with the consecutive method, but more precise. The consecutive method for measuring practice immunization rates could be a useful quality improvement tool as practices seek to improve immunization delivery and quality of care. It is inexpensive, simple, and easy to implement.

Association between parents' preferences and perceptions of barriers to vaccination and the immunization status of their children: a study from Pediatric Research in Office Settings and the National Medical Association.

OBJECTIVES: To assess the association between parents' perceptions of various barriers to vaccination and their preferences regarding specific strategies designed to reduce missed vaccination opportunities and the immunization status of their children and to estimate the overall contribution of the perception of barriers on underimmunization among children who are vaccinated in pediatricians' offices. METHODS: As part of a nationwide study on the immunization status of children followed by practicing pediatricians, parents of children who were 8 to 35 months of age and seen consecutively at 177 participating practice sites completed a survey on health beliefs regarding the vaccination process. In addition to demographic information, parents were asked to identify the most difficult thing about obtaining immunizations, as well as their preferences regarding the maximum number of vaccine injections that should be administered to their child at 1 visit and for receiving a needed immunization during an office visit for a mild illness. Immunization data on study children were abstracted from the practice medical record, and specific survey responses for each parent were compared with the immunization status of his or her child at 8 months of age using chi2 tests. For parental health beliefs associated with immunization status by bivariate analyses, the relative risks for underimmunization and population-attributable risk percentages of each belief were calculated after potentially confounding variables were adjusted for. RESULTS: Immunization data were collected on 13 520 children; 13 516 parents responded to at least 1 question regarding vaccination health beliefs. Two thirds of the responding parents indicated that their child should receive no more than 2 immunizations at 1 visit. However, there was no difference in the preferred maximum number of vaccines between parents of children who were fully immunized at 8 months of age and those of underimmunized children. Similarly, there was no difference in a stated preference for receiving a needed immunization during an illness visit. Overall, 74% of respondents indicated that there was "nothing" difficult about obtaining vaccines for their children. The most commonly cited barrier was concern about the side effects of vaccines, identified by 22.6% of parents. However, this barrier was not associated with immunization status. Each of the remaining barriers-including the confusing vaccination schedule, expense of vaccines, the inconvenience of the vaccination process, having a child who was often too ill to receive vaccines, religious objections, and other identified barriers-was statistically associated with immunization status, with adjusted relative risks for underimmunization ranging from 1.42 to 3.04. However, because each of these barriers was identified as important by <5% of parents, the population-attributable risk percentage for each was < or =2.5%. Overall, it was estimated that parental perception of barriers associated with immunization status accounts for 8.0% of the underimmunization observed among children who are vaccinated in the offices of primary care pediatricians. CONCLUSIONS: Parental preferences regarding vaccination practices designed to reduce missed opportunities were not associated with the immunization status of their children. Although several barriers to vaccination were associated with immunization status, individual barriers were identified by a small minority of parents. Overall, parental perceptions of barriers to vaccination do not seem to be a significant cause of underimmunization in this population of children.

Practitioner policies and beliefs and practice immunization rates: a study from Pediatric Research in Office Settings and the National Medical Association.

OBJECTIVE: To identify vaccination policies and beliefs associated with practice immunization rates (PIR) among office-based pediatricians. METHODS: Primary care pediatricians recruited from the Pediatric Research in Office Settings (PROS) network of the American Academy of Pediatrics or the Pediatric Section of the National Medical Association abstracted immunization data from a consecutive sample of children who were 8 to 35 months old and seen in the office for any reason; 1 provider per practice collected this information. PIR were determined at 8 and 19 months of age by calculating the percentage of children in the sample who were fully immunized at that age. Before collecting the immunization data, all practitioners in each participating practice completed a questionnaire detailing his or her policies and beliefs regarding the administration of vaccines. Part of the questionnaire was a scenario involving a 4-month-old child who was due for a diphtheria-tetanus-acellular pertussis immunization at a health supervision visit. A list of 13 possible clinical conditions in this hypothetical patient were presented; practitioners were asked which of these were a contraindication to vaccination. One set of policies and beliefs was computed for each practice using a weighted average of the responses of each provider in a particular practice. Regression analyses were used to assess the association between each policy and belief and PIR at 8 and 19 months, after controlling for potentially confounding sociodemographic characteristics. RESULTS: Data were analyzed from 112 practices; median PIR at 8 and 19 months were 85% and 71%, respectively. The following policies and beliefs were not statistically associated with PIR at either 8 or 19 months: use of acute visits for vaccinations, conducting an immunization audit within the previous 12 months, perceived difficulties in implementing new vaccine recommendations or staying informed about new recommendations, conducting practice meetings to discuss immunization policies, perception of profitability of providing vaccinations, appointment reminders for scheduled visits, and specific tracking mechanisms for patients who are due for or behind in immunizations. After controlling for sociodemographic characteristics, recommending inactivated poliovirus vaccine and having fewer contraindications to vaccination were associated with statistically higher PIR at 8 months and 19 months. Increasing the maximum number of injections administered at 1 visit was associated with a higher PIR at 8 months but not 19 months of age. CONCLUSION: Policies and beliefs linked to many official recommendations for increasing immunization rates were not associated with higher PIR. However, accepting fewer contraindications to vaccination, administering all vaccines for which an infant is eligible at each health supervision visit, and adopting recommended changes in immunization schedules may help providers fully vaccinate a higher percentage of their patients.

Impact of the change to inactivated poliovirus vaccine on the immunization status of young children in the United States: a study from pediatric research in office settings and the National Medical Association.

OBJECTIVE: To determine whether the change from an all oral poliovirus vaccine (OPV) schedule to an inactivated poliovirus vaccine (IPV)-containing schedule has adversely affected the immunization status of young children in the United States. METHODS: Immunization data were abstracted from the medical records of children 8 to 35 months old seen consecutively for any reason in the offices of practicing pediatricians who are members of the Pediatric Research in Office Settings network of the American Academy of Pediatrics or the National Medical Association. Data on up to 120 eligible children were collected in each practice between March 1998 and January 2000. Patients were classified as fully immunized at 8 months old if they had received 3 diphtheria-tetanus-pertussis, 2 Haemophilus influenzae type b, 2 hepatitis B, and 2 poliovirus vaccines. Study children who were >/=12 months of age at the time that data were collected were categorized as being fully immunized at 12 months if they had received the same vaccines before their first birthday. To assess the effect of type of poliovirus vaccines on these outcomes, study patients were classified as being in an IPV or OPV group based on the initial type of vaccine received. Logistic regression was used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) for IPV as a predictor of being fully immunized at 8 and 12 months of age, after adjusting for race/ethnicity of the patient, maternal education level, year of birth, and method of payment for vaccines. In addition, the effect of clustering of children within practices was accounted for by the use of generalized estimation equation techniques. RESULTS: Data were analyzed on 13 520 children from 177 practices in 42 states; 79.4% of patients were fully immunized at 8 months of age, and 88.7% of those eligible were fully immunized at 12 months of age. A total of 6910 patients (51.1%) were classified as OPV recipients, wheras 5282 (39.1%) received IPV. In addition, 1328 children (9.8%) were documented as having received poliovirus vaccine, but the particular type could not be determined. Compared with OPV recipients and after controlling for the confounding variables and the effect of clustering within practices, children in the IPV group were as likely as were OPV recipients to be fully immunized at 8 months of age (OR: 1.04; 95% CI: 0.88,1.23). At 12 months of age, the OR for IPV as a predictor of being fully immunized was 1.08 (95% CI: 0.90,1.30). When compared with OPV recipients, adjusted ORs for children in the undetermined poliovirus vaccine type group being fully immunized at 8 and 12 months of age were 0.84 (95% CI: 0.68,1.04) and 0.84 (95% CI: 0.67,1.07), respectively. CONCLUSIONS: The results of this national study indicate that the implementation of an IPV-containing poliovirus vaccine schedule has not had an adverse effect on the immunization status of young children who were vaccinated in the offices of practicing pediatricians.