Immunization status of children enrolled in a hospital-based medicaid managed care practice: the importance of the timing of vaccine administration

Impact of pharmacist integration in a pediatric primary care clinic on vaccination errors: a retrospective review

OBJECTIVE

To measure the impact of ambulatory clinical pharmacist integration in a pediatric primary care clinic on vaccination error rates and to evaluate missed opportunities.

METHODS

A retrospective, quasi-experimental review of electronic medical records of visit encounters during a 3-month period compared vaccine error rates and missed opportunities between two pediatric residency primary care clinics. The intervention clinic has a full-time ambulatory clinical pharmacist integrated into the health care team. Pharmacy services were not provided at the comparison clinic. A vaccine error was defined as follows: doses administered before minimum recommended age, doses administered before minimum recommended spacing from a previous dose, doses administered unnecessarily, live virus vaccination administered too close to a previous live vaccine, and doses invalid for combinations of these reasons.

RESULTS

900 encounters were randomly selected and reviewed. The error rate was found to be 0.28% in the intervention clinic and 2.7% in the comparison clinic. The difference in error rates was found to be significant (P = 0.0021). The number of encounters with greater than or equal to one missed opportunity was significantly higher in the comparison clinic compared with the intervention clinic (29.3% vs. 10.2%; P <0.0001).

CONCLUSION

The pediatric primary care clinic with a pharmacist had reductions in vaccination errors as well as missed opportunities. Pharmacists play a key role in the pediatric primary care team to improve the appropriate use of vaccines.

Pediatric immunization-related safety incidents in primary care: A mixed methods analysis of a national database

Background

Children are scheduled to receive 18–20 immunizations before their 18th birthday in England and Wales; this approximates to 13 million vaccines administered per annum. Each immunization represents a potential opportunity for immunization-related error and effective immunization is imperative to maintain the public health benefit from immunization. Using data from a national reporting system, this study aimed to characterize pediatric immunization-related safety incident reports from primary care in England and Wales between 2002 and 2013.

Methods

A cross-sectional mixed methods study was undertaken. This comprised reading the free-text of incident reports and applying codes to describe incident type, potential contributory factors, harm severity, and incident outcomes. A subsequent thematic analysis was undertaken to interpret the most commonly occurring codes, such as those describing the incident, events leading up to it and reported contributory factors, within the contexts they were described.

Results

We identified 1745 reports and most (n = 1077, 61.7%) described harm outcomes including three deaths, 67 reports of moderate harm and 1007 reports of low harm. Failure of timely vaccination was the potential cause of three child deaths from meningitis and pneumonia, and described in a further 113 reports. Vaccine administration incidents included the wrong number of doses (n = 476, 27.3%), wrong timing (n = 294, 16.8%), and wrong vaccine (n = 249, 14.3%). Documentation failures were frequently implicated. Socially and medically vulnerable children were commonly described.

Conclusion

This is the largest examination of reported contributory factors for immunization-related patient safety incidents in children. Our findings suggest investments in IT infrastructure to support data linkage and identification of risk predictors, development of consultation models that promote the role of parents in mitigating safety incidents, and improvement efforts to adapt and adopt best practices from elsewhere, are needed to mitigate future immunization-related patient safety incidents. These priorities are particularly pressing for vulnerable patient groups.

Accuracy and usefulness of the HEDIS childhood immunization measures

OBJECTIVE

With the use of Centers for Disease Control and Prevention (CDC) immunization recommendations as the gold standard, our objectives were to measure the accuracy ("is this child up-to-date on immunizations?") and usefulness ("is this child due for catch-up immunizations?") of the Healthcare Effectiveness Data and Information Set (HEDIS) childhood immunization measures.

METHODS

For children aged 24 to 35 months from the 2009 National Immunization Survey, we assessed the accuracy and usefulness of the HEDIS childhood immunization measures for 6 individual immunizations and a composite.

RESULTS

A total of 12 096 children met all inclusion criteria and composed the study sample. The HEDIS measures had >90% accuracy when compared with the CDC gold standard for each of the 6 immunizations (range, 94.3%-99.7%) and the composite (93.8%). The HEDIS measure was least accurate for hepatitis B and pneumococcal conjugate immunizations. The proportion of children for which the HEDIS measure yielded a nonuseful result (ie, an incorrect answer to the question, "is this child due for catch-up immunization?") ranged from 0.33% (varicella) to 5.96% (pneumococcal conjugate). The most important predictor of HEDIS measure accuracy and usefulness was the CDC-recommended number of immunizations due at age 2 years; children with zero or all immunizations due were the most likely to be correctly classified.

CONCLUSIONS

HEDIS childhood immunization measures are, on the whole, accurate and useful. Certain immunizations (eg, hepatitis B, pneumococcal conjugate) and children (eg, those with a single overdue immunization), however, are more prone to HEDIS misclassification.

Associations between childhood vaccination status and medical practice characteristics among white, black, and Hispanic children

BACKGROUND

The purpose of the study was to identify and understand associations between characteristics of medical practices where immunization services are delivered and vaccination status among white, black, and Hispanic children aged less than 19 months.

METHODS

Eighty pediatric and family physicians participated in a physician-patient encounters survey that included 684 children aged less than 19 months who received at least 1 vaccination during a randomly selected week in 2003.

RESULTS

According to physicians' responses to survey questions, white children who used large medical practices, and black and Hispanic children who used practices, all enrolled in the Vaccine for Children (VFC) program, were more likely to receive vaccines at the recommended age, but Hispanic children who used large Medicaid practices were less likely to receive them at the recommended age. White children who used medical practices that had a large minority patient population were more likely to have completely missed whole series of vaccines.

CONCLUSION

Medical practice characteristics varied in importance as determinants of childhood vaccination among white, black, and Hispanic children. Understanding how type of medical practice and other medical practice characteristics may impact the receipt of timely preventive health services is vital to improving health care access in underserved populations.

Pediatric vaccination errors: application of the "5 rights" framework to a national error reporting database

Little is known about vaccination errors. We analyzed 607 outpatient pediatric vaccination error reports from MEDMARX, a nationwide, voluntary medication error reporting system, occurring from 2003 to 2006. We used the "5 Rights" framework (right vaccine, time, dose, route, and patient) to determine whether vaccination error types were predictable. We found that "wrong vaccine" errors were more common among look-alike/sound-alike groups than among vaccines with no look-alike/sound-alike group. Scheduled vaccines were more often involved in "wrong time" errors than seasonal and intermittent vaccines. "Wrong dose" errors were more common for vaccines whose dose is weight-based and age-based than for vaccines whose dose is uniform. "Wrong route" and "wrong patient" errors were rare. In this largest-ever analysis of pediatric vaccination errors, error types were associated with predictable vaccine-related human factors challenges. Efforts to reduce pediatric vaccination errors should focus on these human factors.

Compliance with vaccination recommendations for U.S. children

BACKGROUND

Official recommendations for the routine vaccination of U.S. children, made by the Advisory Committee on Immunization Practices (ACIP), specify the vaccines for administration, the number of doses that should be given, the age ranges for administration, the minimum ages at which doses are considered valid, the minimum intervals between doses within a series, and several additional vaccine-specific adjustments and exceptions. Federally reported estimates of vaccination coverage measure only compliance with the required number of doses; other recommendations are not routinely evaluated.

METHODS

Analysis of vaccination histories for 17,563 U.S. children aged 19-35 months from the 2005 National Immunization Survey.

MAIN OUTCOME MEASURES

Compliance with, and incremental impact of, each vaccination recommendation.

RESULTS

Estimated coverage was 72% for the standard vaccination series accounting for all recommendations, 9 percentage points lower than coverage based solely on counting doses. Overall, 19% of children were missing one or more doses, while 8% had received an invalid dose, and 9% were affected by other recommendations. The proportion of noncompliance due to missed doses versus other recommendations varied by state and by antigen.

CONCLUSIONS

Approximately 28% of children were not in compliance with the official vaccination recommendations. Missed doses accounted for approximately two thirds of noncompliance, with the remainder due to mis-timed doses and other requirements. Measuring compliance with all ACIP recommendations provides a valuable tool to assess and improve the quality of healthcare delivery and ensure that children and communities are optimally protected from vaccine-preventable diseases.

Assessment of delay in age-appropriate vaccination using survival analysis

Assessment of delay in age-appropriate vaccination provides more information about timeliness of vaccination than up-to-date vaccination coverage. The authors applied survival analysis methods to data from a vaccination coverage survey among children aged 13-59 months conducted in Argentina in 2002. By age 19 months, 43% of children (95% confidence interval (CI): 40, 46) were vaccinated with the fourth dose of diphtheria, tetanus, and pertussis (DTP4). By age 13 months, 55% of children (95% CI: 52, 57) were vaccinated with measles-containing vaccine. By age 7 months, 33% of children (95% CI: 27, 40) were vaccinated with the third dose of hepatitis B. Compared with firstborn children, third children were more likely to be delayed for DTP4 (relative risk (RR) = 1.41, 95% CI: 1.22, 1.62), measles-containing vaccine (RR = 1.54, 95% CI: 1.32, 1.78), and the third dose of hepatitis B (RR = 1.31, 95% CI: 1.03, 1.67). Children whose caregivers had completed secondary school were less likely to be delayed for DTP4 (RR = 0.68, 95% CI: 0.52, 0.90) compared with those whose caregivers had not completed primary school. Survival analysis methods were helpful in measuring vaccine uptake and should be considered in future surveys when assessing delay in age-appropriate vaccination.

Compliance with national immunization guidelines for children younger than 2 years, 1996-1999

OBJECTIVES

To evaluate compliance with national immunization guidelines among a large cohort of children cared for at health maintenance organizations (HMOs) and to examine effects on immunization status.

METHODS

A cohort study of 176134 children born between January 1, 1994, and December 31, 1997, and monitored from birth to the second birthday was performed. Subjects belonged to the Vaccine Safety Datalink Project, a study of children enrolled in 1 of 4 HMOs. Children were continuously enrolled in a HMO for the first 2 years of life. Prevailing recommendations regarding optimal ages of immunization and intervals between doses were applied to define appropriate immunization timing and immunization status. Noncompliance was defined as having a missing or late immunization or an immunization error. Immunization errors included invalid immunizations (too early to be acceptable), extra immunizations (superfluous immunizations or make-up immunizations for invalid immunizations), and missed opportunities resulting in late or missing immunizations.

RESULTS

Although 75.4% of children in these HMOs were up to date for all immunizations at 2 years, only 35.6% of children were fully compliant with recommended immunization practices. Less than 8% of children received all immunizations in accordance with strict interpretation of recommended guidelines. Fifty-one percent of children had at least 1 immunization error by age 2 years; 29.7% had a missed opportunity with subsequent late or missing immunization, 20.4% had an invalid immunization, and 11.6% had an extra immunization. Common reasons for noncompliance included missed opportunities for the fourth Haemophilus influenzae type b vaccine (14.6%), invalid fourth diphtheria-tetanus-pertussis/acellular pertussis immunizations (11.0%), and superfluous polio immunizations (9.8%).

CONCLUSIONS

Approximately 35.6% of children were compliant with prevailing childhood immunization recommendations from 1996 to 1999. Efforts to improve compliance with guidelines are recommended, to optimize childhood infectious disease prevention.

Impact of the Advisory Committee on Immunization Practices' 4-day grace period in a low-income community

BACKGROUND

In 2002, the Advisory Committee on Immunization Practices (ACIP) recommended vaccine doses administered < or = 4 days before the minimum age or interval be counted as valid. The study objective was to assess the impact of the 4-day grace period on the need for revaccination and associated costs in a low-income community, compared to standard practice (i.e., repeating all doses that fall outside current ACIP guidelines).

METHODS

From 1999 to 2001, semi-annual immunization assessments of 8293 randomly selected children, aged 19-35 months, were conducted at a 16-practice network serving an underserved community in New York City. Outcome measures were rates of antigen-specific invalid doses and number of children needing revaccination, with and without the 4-day grace period. Revaccination costs were based on the Vaccines for Children (VFC) price list.

RESULTS

The 4-day grace period reduced the number of children needing revaccination from 17.1% to 12.0%, a drop of 30%. The rates of invalid doses decreased from 1.9% to 1.3%, a drop of 33%. Invalid doses for hepatitis B (HepB)-2 decreased by two thirds (69.7%); for diphtheria-tetanus-acellular pertussis (DTaP)-1, Haemophilus influenzae type b (Hib)-1 and Hib-3 by half (44.9%-50.0%); for Polio-1, Polio-2, Polio-3, and measles-mumps-rubella (MMR) by one third (31.6%-33.3%); and for DTaP-2, DTaP-3, HepB-3, and varicella by nearly one quarter (20.0%-24.0%). At these rates, revaccinating 100,000 children younger than age 3 years would cost 213,588 dollars per year, compared to 152,539 dollars with the 4-day grace period, in vaccine costs alone.

CONCLUSIONS

In a low-income community, ACIP's 4-day grace period made a significant impact on the number of children requiring revaccination and on revaccination costs. However, the number of children needing revaccination remains high.

The immunization delivery effectiveness assessment score: a better immunization measure?

BACKGROUND

Childhood immunization measures, such as the Health Employer Data Information Set (HEDIS) or the National Immunization Survey, assess the percentage of children up-to-date for a specified series of vaccinations. In particular, the HEDIS assesses immunization delivery to children enrolled in managed care organizations (MCO). Such measures do not assess the timeliness of immunization delivery with reference to recommended age standards. To achieve maximal protection against vaccine-preventable diseases, children should receive all immunizations within recommended age intervals-fully "on-time."

OBJECTIVE

The Immunization Delivery Effectiveness Assessment (IDEA) is a novel immunization measure that assesses, on a continuous scale, the timeliness of administration of each vaccination with reference to recommended age intervals. Specifically we ask: 1) Do absolute immunization rates differ between HEDIS and IDEA? 2) Does relative MCO performance differ when assessed by the 2 performance measures? 3) How well do MCOs perform relative to the standard of fully on-time immunization? The health services implications of using the timeliness standard to assess childhood immunization delivery is discussed.

METHODS

A vaccine-dose IDEA score was developed for each of the 14 vaccination events in the 4:3:1:3:3 combination series (4 diphtheria-pertussis-tetanus:3 polio:1 measles-mumps-rubella:3 Haemophilus influenzae type B:3 hepatitis B). Assessing the actual age of administration with reference to the recommended age of administration generates the vaccine-dose IDEA score. A child's composite IDEA score is obtained by averaging the 14 vaccine-dose IDEA scores. These composite IDEA scores, when averaged among children sampled within the MCO, constitute the MCO's immunization score.

SETTING

Retrospective analysis of childhood immunization datasets from a convenience sample of 6 MCOs in 5 states.

RESULTS

HEDIS rates ranged from 57% to 75%. IDEA scores ranged from 80% to 90%. Relative rankings of MCO immunization performance were different using HEDIS rates and IDEA scores, respectively. At most, 16% of children in any of these MCOs received all of their immunizations fully on-time. From 47% to 77% of children experienced at least 3 delayed immunizations.

CONCLUSIONS

An immunization measure based on timeliness of administration yields both absolute and relative differences in MCO childhood immunization performance when compared with HEDIS rates. By assessing delivery of each component vaccination, the IDEA score permits more detailed analysis of immunization patterns within an MCO and focuses improvement efforts.

The need for surveillance of delay in age-appropriate immunization

BACKGROUND

Vaccination status is assessed nationally in terms of up-to-date status without regard to the age at which recommended doses were actually received. Our study was conducted in 2000-2001 using the most current National Health Interview Survey (NHIS) public use files available.

METHODS

Retrospective analysis to determine up-to-date and age-appropriate vaccination status for children aged 25 to 72 months. Five years of pooled data (1992-1996) were obtained from the NHIS Immunization Supplement for children aged 25 to 72 months with immunization data based on written records. The outcome measures used were months of vaccination delay relative to age-appropriate vaccination standard as well as up-to-date vaccination status for the fourth diphtheria-tetanus-pertussis (DTP 4), Polio3, the first measles-mumps-rubella (MMR1) doses, and the 4:3:1 series.

RESULTS

Of the 9223 eligible children, 80% were up-to-date for the 4:3:1 vaccination series, but 48% had experienced delays relative to age-appropriate standards. For the DTP4 dose, 85% were up-to-date, although only 46% had received this dose at the appropriate age. Similarly, 90% of children were up-to-date with their Polio3 dose, with 64% receiving this dose at the appropriate age; 96% were up-to-date for the MMR1, and 58% received this dose at the appropriate age. Age-appropriate DTP4 vaccination increased by 17 percentage points from 1992 to 1996, whereas up-to-date DTP4 status increased by only 6% during the same period.

CONCLUSIONS

Children with up-to-date vaccination status often experienced considerable delay relative to age-appropriate vaccination standards. Consequently, vaccination status measures based solely on up-to-date status tend to understate the degree of underimmunization in a population. National surveillance of age-appropriate vaccination is necessary to identify subpopulations with the greatest prevalence of vaccination delay and to reveal underlying trends that may not be evident through assessments of up-to-date status.

An analysis of the immunization status of preschool children enrolled in a statewide Medicaid managed care program

OBJECTIVES

To measure immunization coverage rates for children enrolled in a statewide Medicaid managed care program and determine the impact of sociodemographic characteristics and the type of primary care provider site on immunization coverage.

STUDY DESIGN

A random sample of 2000 was chosen from children between the ages of 19 and 35 months who had been continuously enrolled in the Medicaid managed care program for 1 year. Sociodemographic data and a list of primary care providers for the study children were obtained from administrative databases. Immunization histories were determined by medical record review.

RESULTS

Vaccine-specific immunization rates for diphtheria-tetanus-pertussis, polio, Haemophilus influenzae type b, hepatitis B, and measles-mumps-rubella ranged from 87% to 94%, with an overall coverage rate of 75%. Overall immunization status varied by primary care provider site as follows: office-based, 72%; community health center, 75%; hospital-based clinic, 79%; and staff model health maintenance organization, 85% (chi(2) test, P =.008).

CONCLUSIONS

Immunization rates compare favorably with national rates for this low-income group. Sociodemographic characteristics were not important predictors of underimmunization, but rates did vary by the type of primary care provider site.

Strict interpretation of vaccination guidelines with computerized algorithms and improper timing of administered doses

BACKGROUND

Frequently changing immunization recommendations may lead to incorrectly administered doses.

OBJECTIVE

To determine the incidence and characteristics of inappropriately timed vaccinations.

METHODS

Prospectively collected immunization histories of patients <5 years old from well-child care encounters with pediatric residents in a large urban clinic during a 3-month study period. New patients or those with no immunization history in the medical record were excluded. Paper records were verified before each visit and served as the immunization history. Immunization records were entered into and analyzed by the Massachusetts Immunization Information System with strict interpretation of minimum spacing and age guidelines to identify invalid vaccine doses. Reasons for invalidity were determined by manual review. Invalid doses were cross-referenced with clinic schedule to determine who delivered doses.

RESULTS

Inclusion criteria were met by 690 encounters. Charts were available for review before the encounter for 580, containing 6983 total immunizations. Of these 289 (4.1%) administered doses were invalid; 206 of 580 (35.5%) patients had at least one invalid dose. Common invalid doses given were unnecessary poliovirus vaccine around 18 months (n = 66) and second hepatitis B vaccine given too soon after the first (n = 53). All types of providers gave invalid doses; pediatric residents and fellows delivered significantly more (P < 0.01).

CONCLUSIONS

By strict interpretation of immunization guidelines, many patients were immunized incorrectly. Clinicians should be aware of common errors in vaccine dosing and national guidelines should be simplified.

Insights on immunizations from caregivers of children receiving Medicaid-funded services

ISSUES AND PURPOSE

Despite numerous programs aimed at improving immunization rates among American children, under-immunization remains a significant problem. This study was conducted to gain insight into parents'/guardians' knowledge and attitudes regarding childhood immunizations.

DESIGN AND METHODS

Thirteen African-American mothers and grandmothers participated in semistructured, audiotaped focus-group interviews.

RESULTS

Four major themes emerged: health knowledge and beliefs about immunizations, system barriers that impede obtaining immunizations, facilitators that enhance obtaining immunizations, and suggestions for change.

PRACTICE IMPLICATIONS

Immunizations are one of the most important health advantages available to children. Therefore, nurses must become aware of the problem of underimmunization and work to address some of the concerns caregivers have identified in this study. The health and lives of the nation's children depend on it.