Hopeful signs of

1

The Revised Birth Data
Hopeful signs of change amid struggle
The NAPHSIS/NCHS Collaboration Past Successes and
Future Challenges Salt Lake City, UT June
3rd-7th, 2007
2

Authors/Acknowledgments
Joyce Martin Stephanie Ventura The Birth
Team Brady Hamilton Fay Menacker Sharon
Kirmeyer Martha Munson Marian MacDorman Paul
Sutton TJ Mathews
U.S. Department of Health and Human
Services Centers for Disease Control and
Prevention National Center for Health
Statistics National Vital Statistics System
3

Revision Status, 2007
Revised
NYC
Unrevised
4

Todays Topics

• Key items on both revised unrevised birth
  certificates
• Prenatal care
• Cesarean delivery
• Checkboxes items
• Diabetes and hypertension

5
Methods

• Total 2005 revised states (12)
• (1.3 m births)
• Excludes mid-year revisers
• Trends - states which revised in
• 2004 (5) or 2005 (3)
• Excludes mid-year revisers

6
Prenatal Care
Unrevised
Source ? mom, records
7
Prenatal Care
Revised
Source prenatal records, mom ?
8
Percent of Records with Not Stated Day Month of
1st prenatal visit 12 Revised States, 2005
Source NCHS/CDC/National Vital Statistics System
9
Percent of Records with Not Stated Day of 1st
Prenatal Visit 12 Revised States, 2005
Source NCHS/CDC/National Vital Statistics System
10
NCHS Calculation ofMonth Prenatal Care Began

• Difference between Date of 1st PNCV Date of
  last normal menses
• If day of 1st PNCV unk,
• impute day from last record w/ same month of 1st
  PNCV
• SAS code to calculate now available from NCHS

11
1st Trimester Prenatal Care by Revised Status3
Revised states, 2004 and 2005
State B
State C
State A
Source NCHS/CDC/National Vital Statistics System
12
Percent change in 1st Trimester Prenatal Care,
Unrevised and Revised Reporting Areas 2004-2005

Unrevised
Revised
Source NCHS/CDC/National Vital Statistics System
13
Timing of Prenatal Care

• Large discontinuity between
• unrevised and revised PNC data
• Revised levels much less favorable
• Some difference was expected
• Changes in question sources of data?
• Studies show moms tend to over-report
• Wide differences in unknown levels by reporting
  area

14
Cesarean Delivery

• 3 commonly used measures
• Total cesarean delivery rate
• Primary cesarean rate
• Vaginal birth after previous cesarean (VBAC)

15
Cesarean Delivery
Revised
Unrevised

• Total cesarean rate
• Very comparable between revisions

16
Cesarean Delivery - Revised

• Primary cesarean
• VBAC/Repeat cesarean
• Need info on both current and previous deliveries
  -
• derived from 2 separate items
• Method of delivery
• Pregnancy risk factors
• Mother had a previous cesarean (from moms
  prenatal records)

17
Cesarean Delivery- Revised
18
Primary Cesarean Delivery Rates for Unrevised
States and for States which Revised in 2005
Reporting Area, 2004-2005
State B
Reporting area
State C
State A
Source NCHS/CDC/National Vital Statistics System
19
VBAC Rates for Unrevised States and for States
which Revised in 2005 Reporting Area, 2004-2005
State B
Reporting area
State C
State A
Source NCHS/CDC/National Vital Statistics System
20
Primary Cesarean Delivery and VBAC Rates by
Revised Status Reporting area, 2005
Primary
VBAC
Source NCHS/CDC/National Vital Statistics System
21
Cesarean Delivery

• NCHS no longer considers Primary Cesarean and
  VBAC data comparable across revisions
• Revised data may be improved
• Revised rates higher than unrevised (previously
  thought under-reported)
• Better agreement w/other sources

22
Cesarean Delivery

• BUT,
• possible under-reporting
• of previous cesareans
• Developing enhanced
• instructions for reporting
• if mom had a previous
• cesarean using prenatal
• and other medical records

23
Pregnancy Risk Factors

• Diabetes
• Unrevised Total Diabetes only
• Revised Pre-pregnancy gestational diabetes
• Possible change in source of data
• Gestational hypertension
• No change except possibly to sources of data

Source NCHS/CDC/National Vital Statistics System
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Total Diabetes (Pre-pregnancy Gestational) for
states which revised in 2004 and 2005 Reporting
Area, 2003-2005
G
B
D
E
C
A
F
H
Source NCHS/CDC/National Vital Statistics System
25
Gestational Hypertension Rates for States which
Revised in 2004 and 2005 Reporting Area,
2003-2005
G
B
D
E
C
A
F
H
Source NCHS/CDC/National Vital Statistics System
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Diabetes and Pre-pregnancy Hypertension
Unrevised Reporting Area 2004-2005

Pre-pregnancy hypertension
Diabetes
Source NCHS/CDC/National Vital Statistics System
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New Report

• Begins to
• demonstrate
• the tremendous
• analytic potential
• of the revised data

Source NCHS/CDC/National Vital Statistics System
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Summary

• Prenatal care
• Large discontinuities higher levels of
  unknowns revised data may still be more
  accurate
• Primary, Repeat and VBAC
• Not comparable developing improved
  instructions for hospitals
• Very encouraging signs of improved
• data quality for checkbox items
• Need validation studies !!!