1. 42nd National Immunization Conference Atlanta, GA April 20, 2010
Integrating Electronic Information to Improve Documentation of Immunization Rates for a Low-Income, Minority Population
Melissa Stockwell Karthik Natarajan, Amy Metroka, Angel Aponte, Yiye Zhang, David Vawdrey Division of General Pediatrics, Department of Pediatrics Department of Population Family Health Department of Biomedical Informatics Department of Biostatistics
CityWide Immunization Registry (CIR), New York City Department of Health and Mental Hygiene 
42nd National Immunization Conference Atlanta, GA April 20, 2010 

2. Background
Urban low-income, minority children are at high risk for underimmunization
Fragmented records from multiple providers
May also be at risk of overimmunization
City or regional IIS ameliorate effect of scatter
Stokley S et al 2001; Yusuf H et al 2002; Santoli JM et al 2000, Yawn BP, 1998

3. IIS Data in End User EHR
Having registry data readily available in electronic health record (EHR) is important
Missed opportunities/over immunizations due to incomplete records
Time saving

4. EzVAC NewYork-Presbyterian Hospital (NYP) Immunization Registry, EzVAC
Point-of-service registry
Over 140,000 children, adolescents and adults, 1.3 million vaccinations
Linked to hospital billing system
Includes all children receiving care at hospital and affiliated ambulatory clinics

5. New York Citywide Immunization Registry (CIR)
Population-based registry
4.3M individuals with 47M immunizations
Load birth certificates.
Mandated reporting of vaccines administered to patients ≤18 given by providers in NYC
CIR captures >85% immunizations administered, 93% of Vaccines For Children (VFC) immunizations
Papadouka et al. New York City Department of Health and Mental Hygiene "Impact of Childhood Hepatitis A Vaccination: New York City". 41st National Immunization Conference (Kansas City); March 2007
Metroka AE et al 2009

6. Objective
1) To describe how a local and a city wide IIS can exchange data real time 2) To assess the impact on immunization record completeness and coverage rates of integrating data from a public IIS into a hospital information system

7. CIR-Web Service
CIR recently provided secure web-services allowing immunization data to be queried from CIR
Web-services allow systems to communicate outside of an organization’s firewall over the Internet
Batch as well as single real time queries
Opportunity to put IIS information directly into end user EHR
Previously had to manually look up patient in CIR

8. CIR-Web Service Development
Investment in bi-directional integration
Uses HL7 version VXQ (query) and VXU (update) messages delivered over SOAP/XMLP
~ 9 Months of requirements, design, implementation, testing, and deployment

9. EHR Queries Must find 1 unique match
Data combined to perform 30+ exact match database queries then 1 approximate search
Ex: Last name, MRN, facility; First Name, Last Name, DOB, Gender
Median response time is 2 seconds

10. Querying Webservice
End users uses EzVAC to query CIR web service with patient name, DOB, local MRN
Downloads immunization information and tags it with CIR as source
FIREWALL
CIR
(John Smith, 1/1/01 MRN: 99999)
John Smith’s Immunizations
Missing Iz
EzVac DB

11. Matching
CIR returns immunization data in ~ 88% cases

12. De-Duplication Data run through de-duplication script
Considered duplicate if two vaccines given within 10 days: based on own assessment of synchronization data and IIS literature

13. De-Duplication Class level not vaccine level de-duplication
If discrepancy: preference given to EzVAC as preferred source (own data) and more specific vaccine information ie ActHib rather than Hib NOS

14. EzVAC
CIR

15. Study Setting
NYP Ambulatory Care Network practice sites in Washington Heights/Inwood area of NYC
Disadvantaged community
Primarily Latino, publicly insured
Mobile population

16. Study Population and Design
Random sample children (n=2529), visit in last 12 mths 
7-23 months old (n=950)
24-36 months (n=960)
Adolescents years old (n=619)
Total of 32, 173 children 7-36 months and years old with visit in last 12 months
Immunization record synchronized with CIR (batch query), each vaccine labeled automatically by source (EzVAC vs CIR)

17. Outcome
7-36 months: Age Appropriate up to date immunization status, according to the 4:3:1:3:3:1 series (DTaP, IPV, MMR, Hib, HepB, varicella)
Hib adjusted due to shortage
Adolescent immunizations: TdaP, MCV4 and first HPV

18. Analysis Assessed contribution of each source (EzVAC, CIR)
Test of two proportions: Immunization coverage rates EzVAC alone and EzVAC with CIR

19. Contribution of Source to Record

20. Change in Immunization Rates
* P < 0.05; ** P <0.01; *** P < .001; **** P < 0001

21. Summary Webservice fast, easy, allows real time synchronization
Clinicians found it very useful
Significantly increased record completeness, improved documentation of coverage rates
Brought documented coverage rates for young children above Healthy People 2010 goals
Greatest impact for adolescent patients

22. Limitations Integration Study
Need personnel to set up synchronization by end user into EHR (took 80 estimated person hours programming time)
Deduplication
Trust data
Study
Generalizability of effect size, may have greater effect in pop at greatest risk for record scatter
Did not include all age groups

23. Public Health Implications
Real time, two-way communication regarding immunizations between public and private information systems should be widely considered

24. Acknowledgements Melissa Stockwell, Medical Director
EzVAC Team
Melissa Stockwell, Medical Director
David Vawdrey, Informatics Director
Oscar Pena, Operational Coordinator
Balendu Dasgupta, Programmer
Karthik Natarajan, Programmer/Data Manager
Citywide Immunization Registry (CIR)
Amy Metroka, Director
Angel Aponte, Programmer
Vikki Papadouka, Director of Research and Evaluation
Jane R. Zucker, Assistant Commissioner, Bureau of Immunization, New York City Department of Health)