Title: Immunization Registry and Provider-Reported Vaccination Histories: Assessing Missing Vaccinations
1Immunization Registry and Provider-Reported
Vaccination HistoriesAssessing Missing
Vaccinations
- Linda Piccinino (Abt Associates), Meena Khare
(CDC), Mike Battaglia (Abt Associates), Diana
Bartlett (CDC), Lawrence Barker (CDC)
2NIS REGISTRY DATA QUERY STUDY
- Study integrated registry query consent question
into standard National Immunization Survey (NIS)
interview - Four mature registry sites participated in the
study - Each site had one quarter of data collection (one
site in Q3/2002, three sites in Q4/2002) - Vaccination history data obtained from NIS
provider reports and from state/local registries
for children with parental consent
3RESEARCH PROBLEM
- Need a way to assess the quality of vaccination
data for NIS children with data available from
both NIS provider reports and immunization
registries
4OBJECTIVES OF THIS ANALYSIS
- To compare vaccination histories obtained from
immunization providers and registries for a
sample of NIS children 19-35 months old - To examine the pattern of missing vaccination
data by vaccination type, dose and source of data
5ANALYSIS GROUPS
- Sample consisted of NIS children with both
registry and provider data - Data were combined for four sites because of
sample size and confidentiality concerns
6METHODOLOGY FOR IDENTIFYING MISSING VACCINATIONS
- 323 children with registry vaccination data (at
least one shot) and adequate provider data in the
NIS - Focus on DTaP vaccinations present in one source
but missing from the other source - Children UTD with 4 doses of DTaP in the provider
data (N 245) but fewer than 4 doses in the
registry data (N 75) - Children UTD with 4 doses of DTaP in the registry
data (N 180) but fewer than 4 doses in the
provider data (N 16) - Determine dose number (order) of missing
vaccination(s)
7DETERMINING THE DOSE NUMBER OF MISSING
VACCINATIONS
- Provider data
- (1) 2/15/2001 (2) 8/12/2001 (3) 1/14/2002 (4)
9/03/2002 - Registry data
- 2/15/2001 1/16/2002 8/30/2002
- For each registry vaccination date, determined
which provider vaccination date was closest in
time - DOSE 1 MISSING DOSE 3 DOSE 4
8CHILDREN WITH MISSING DTaP DOSES
- REGISTRY 75 CHILDREN (30.6)
PROVIDER 16 CHILDREN (8.9)
Registry Provider
MISSING MISSING MISSING MISSING 10.7 --
MISSING MISSING MISSING DOSE 4 8.0 6.3
MISSING MISSING DOSE 3 DOSE 4 9.3 12.5
MISSING DOSE 2 MISSING MISSING 2.7 --
MISSING DOSE 2 DOSE 3 MISSING 1.3 --
MISSING DOSE 2 DOSE 3 DOSE 4 6.7 --
DOSE 1 MISSING MISSING MISSING 6.7 6.3
9CHILDREN WITH MISSING DTaP DOSES, contd
- REGISTRY 75 CHILDREN (30.6)
PROVIDER 16 CHILDREN (8.9)
Registry Provider
DOSE 1 MISSING MISSING DOSE 4 6.7 --
DOSE 1 MISSING DOSE 3 MISSING 5.3 --
DOSE 1 MISSING DOSE 3 DOSE 4 6.7 18.7
DOSE 1 DOSE 2 MISSING MISSING 6.7 6.3
DOSE 1 DOSE 2 MISSING DOSE 4 8.0 --
DOSE 1 DOSE 2 DOSE 3 MISSING 21.3 50.0
100 100
10SUMMARY OF MISSING DOSES Dose Order
ORDER OF MISSING DOSES Registry Provider
First dose missing 38.7 18.8
Second dose missing 53.4 43.8
Third dose missing 49.5 18.9
Fourth dose missing 54.7 62.6
11SUMMARY OF MISSING DOSES Dose Frequency
NUMBER OF MISSING DOSES Registry Provider
One dose missing 42.7 68.7
Two doses missing 29.3 18.8
Three doses missing 17.4 12.6
Four doses missing 10.7 0.0
12REASONS FOR MISSING PROVIDER DOSES
- 23 children had more registry doses than provider
doses when all vaccines were examined We
reviewed the Immunization History Questionnaires
(IHQs) and recontacted the providers when
necessary. Extra registry vaccination dose was - very close to another registry vaccination dose
date - the last dose and was omitted from the IHQ or
that dose was administered by a provider who did
not respond to the NIS - not the last dose and was inadvertently omitted
when the IHQ was filled out - for a child with multiple providers but household
respondent only identified one provider - for a child for whom not all identified providers
responded or returned the IHQ with vaccination
data
13IMPLICATIONS FOR DATA QUALITY
- INCOMPLETE VACCINATION HISTORIES
- The vaccination histories were not always
complete. - For children with 4 provider doses of DTaP, about
31 of children had one or more doses missing in
the registry data. - For children with 4 registry doses of DTaP, only
about 9 of children had one or more doses
missing from the provider reports. - These suggest that registry histories tended to
be more incomplete than provider histories.
14IMPLICATIONS FOR DATA QUALITY
- MIXED PATTERN OF MISSING DATA
- The frequency and order of the missing doses for
DTaP varied by source of data. - Therefore, source of data should be considered
when interpreting results and making estimates. - The fourth DTaP dose was the most likely to be
missing in both the provider and registry data,
although the reasons this 4th dose was missing
might differ by data source.
15CONCLUSION
- Results may not be conclusive due to the small
sample size. - Results showed a mixed pattern of missing doses.
- Data quality concerns suggest that building
combined best value estimates may be difficult
since the quality and completeness of registry
data are lacking. - Although there are data quality problems, some
registries were more complete than others. - Results strongly support further research on
supplementing provider-reported immunization
histories with registry data in order to improve
vaccination coverage estimates.
16NEXT STEP
- Future research plans include looking at the
quality of registry data compared to
provider-reported and household-reported
vaccination data from shot cards