1. Assessing the Completeness of Perinatal Hepatitis B Case Reporting Using Capture-Recapture Claire Newbern, PhD MPH Philadelphia Department of Public Health NIC Atlanta, GA 2010

2. Problem Identified Never reach CDC target for perinatal HBV cases –Cases expected annually for Philadelphia: 132 – 185 (old criteria) 180 – 230 (new criteria – NHANES) Perinatal HBV coordinator noted recent decline in referrals to program Mother-child pairs

3. Perinatal HBV Referral in Philadelphia Division of Disease Control Acute Communicable Disease Program Immunization Program Perinatal Hep B Coordinator Follow up on identified pregnant women, newborns, and close contacts Receive reports by fax, phone, & electronically through PA NEDSS For women aged 12-40 years old, disease investigators contacts provider / patient to see if pregnant Refer to Perinatal Hep B Coordinator for follow up

4. Methods: Data Sources Hepatitis B Surveillance Data –HBV tests reported in 2001-2009 (N=11,517 persons) Perinatal HBV Monitoring Database –2008 births to women infected with HBV (N=98) 2008 Birth Certificates –Philadelphia residential address (N=23,471)

5. Methods: Matching Datasets PHBV & Hepatitis B surveillance data separately matched to birth certificates: –Variables used for matching: Mother’s: name, DOB and residential address Child’s: name and DOB (if available) –Automated (SAS 9.1.3) and manual (line lists) matching –Matches between Hep B surveillance & PHBV data based matching to same birth certificate

6. Methods: 2008 Capture-Recapture 2008 Birth Certificates Perinatal HBV Births in 2008 2001- 2009 Hep B Reports

7. Results: 2008 Capture-Recapture 2008 Birth Certificates 2 96 129 227 unique records 96 (42%) in both Hep B & PHBV data 129 (57%) in Hep B data but NOT in PHBV data 2001- 2009 Hep B Reports Perinatal HBV Births in 2008

8. Results: Description of 2008 Missed Cases Internal Issues: Problems with referral to PHBP [52] Women not located [15] External Issues: No test reported during pregnancy [46] Non-case defining test during pregnancy [16] N=129 67 62

9. Follow-Up Actions Infants born to 67 women with case defining tests during pregnancy: 4 pending final serum collection 12 moved or died 51 infants (76%) with completed serology: –0 HBsAg+ –49 (96%) anti-HBs+ (immune) –2 susceptible revaccinated & waiting to do serology again

10. Follow-Up Actions: External 62 women with non-case defining tests –Chart review of women’s records to identify failures of testing and reporting during pregnancy –Pending Outreach / education with providers failing to perform or report case-defining tests during pregnancy –Pending

11. Follow-Up Actions: Internal Improve internal investigation / referral process –Investigate all reported HBV tests on women 12-40 yrs –Added disease investigator with Hep B focus –Conducted education with disease investigators –Started using Lexis-Nexis to find unable to locates –Launching new surveillance database in July 2010 Repeat capture-recapture every 6 months to identify missed cases

12. Impact: 2009 Capture-Recapture 2009 Birth Certificates 1 133 106 240 unique records 133 (55%) in both Hep B & PHBV data 106 (44%) in Hep B data but NOT in PHBV data 2001- 2010 Hep B Reports Perinatal HBV Births in 2009 2008 227 42% 57%

13. Impact: Description of 2009 Missed Cases N=106 Internal Issues: Problems with referral to PHBP [28] Women not located [15] External Issues: No test reported during pregnancy [36] Non-case defining test during pregnancy [27] 43 63 52% : 48% in 2008

14. Conclusions If data are available, capture-recapture (C-R) is: –NOT that labor intensive –Identifies a large number of missed cases –Can help highlight internal / external issues –Can be regularly repeated to find additional cases Mother-child pairs

15. Acknowledgements Co-authors: –Liyuan Ma (Epi) –Robbie Madera (Epi) –Jim Lutz (Imm) –Bruce Barlow (Imm) –Caroline Johnson (DDC) ACD staff: – Ami Patel – Esther Chernak – Marcelo Fernandez-Vina – John Faherty – Terina Perry – Stephan Smith – John O’Callaghan – Xiomara Lugo

16. Questions / SAS Code Claire Newbern claire.newbern@phila.gov