the perinatal periods of risk approach
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The Perinatal Periods of Risk Approach. Phase 1 Analytic Methods. CityMatCH Training August 25, 2007 Denver, Colorado. Workshop Objectives. During this session, participants will have the opportunity to: Recognize and understand the PPOR approach and its six stages - PowerPoint PPT PresentationTRANSCRIPT
The Perinatal Periods of Risk Approach
CityMatCH Training August 25, 2007
Denver, Colorado
Phase 1 Analytic Methods
Workshop ObjectivesDuring this session, participants will have the opportunity to:
• Recognize and understand the PPOR approach and its six stages
• Learn how to assess “community readiness”• Learn how to assess “analytic readiness”
• Understand what it takes to conduct the first phase of analysis
Six Stages:Perinatal Periods of Risk Approach
Stage 1: Assure Analytic and Community Readiness
Stage 2: Conduct Analytic Phases of PPOR Stage 3: Develop Strategic Actions for Targeted
Prevention Stage 4: Strengthen Existing and/or Launch New
Prevention InitiativesStage 5: Monitor and Evaluate ApproachStage 6: Sustain Stakeholder Investment and
Political Will
DEFINITIONS
Traditional Infant Mortality Rate “IMR” is deaths before first birthday, per thousand live births
=deaths x 1,000 ÷ births
This can be done for any subpopulation, for example, the White IMR would be white deaths before first birthday, per thousand white live births
Definitions
Ideally, we use a BIRTH COHORT, count births in one year, and watch those babies until they reach their first birthday (must wait until the end of the following year ) to count deaths.
Often, we use a DEATH COHORT count births in one year, count deaths IN THE SAME YEAR. This is an easy way to approximate the true mortality rate.
Infant Mortality Rate,Infant Mortality Rate,Urban County, 1990-2001Urban County, 1990-2001
0.0
5.0
10.0
15.0
20.0
25.0
30.0
Black
White
Source: DHHS
What do PPOR analytic methods bring “to the table”
The Importance of Fetal DeathsOne difference between PPOR and traditional analysis is that PPOR includes fetal deaths, an important part of the picture.
Fetal and Infant Mortality Rates, 5 Urban Counties
8.5
9.2
7.1
9.9
7.9
8.9
5.7
8.3
6.1
7.2
0 5 10 15 20
Urban E
Urban D
Urban C
Urban B
Urban A
FetalInfant
PPOR Uses a Reference Group
• A subpopulation with optimal outcomes or an external population
• Comparison of target population with reference group helps target deaths that could be prevented.
PPOR Examines Deaths in TWO dimensions simultaneously:
• Age at death
• Weight at birth
Conce
ption Birt
h1
Year
Fetal Infancy20 wks 28 wks
4 wks
Spontaneous Abortion
Early Fetal
Late Fetal Neonatal
Postneonatal
Infant
Feto-Infant
Age at Death
The First Dimension Of PPOR Analysis:
Second Dimension: Birthweight
• Very Low Birthweight (PPOR limit)= less than 1500 grams (3.3 pounds)
• Low Birthweight= less than 2500 grams (5.5 pounds)
• Normal Birthweighte.g., a 7.5-pound baby weighs 3,400 grams
Birth
weig
ht
PPOR ANALYTIC METHODS Steps of Analytic Preparation
Acquire access to three required vital records computer files
Prepare vital records files and required data elements
Assess data quality
Assess study sample size
PPOR Analytic PreparationPPOR Analytic Preparation
• Fetal death certificate files (24+ wks, 500+ grams)
• Infant death certificate files (500+ grams)
• Live birth files (500 + grams)
• Linked birth—infant death certificate files are needed to find birth information for the infants who died
• Spontaneous and induced abortions are NOT included (they are not given certificates)
Analytic Preparation—Number of DeathsAnalytic Preparation—Number of Deaths
• At least sixty deaths overall and at least ten deaths in each period of risk, for each population being studied
• May combine UP TO 5 years to reach adequate number of deaths (no more, due to changes in medical practice)
• Phase 2 analyses require even more deaths.
Analytic Preparation – Data QualityAnalytic Preparation – Data Quality
• Serious bias is introduced if more than 5-10% of births, deaths, and fetal deaths are missing key data items such as birthweight, age at death, and maternal characteristics.
• Imputation (educated guessing) can help when key data are missing: e.g. if gestational age >=31 weeks we impute birthweight >=1500 grams
Relationship Between Gestational Age and Median Birthweight
0
500
1000
1500
2000
2500
3000
3500
Gestational Age (Weeks)
Infant DeathsFetal Deaths
Imputation I: Fetal Deaths
GA>=32 BW>=1500Y
N
GA>=24 Y500<=BW<1500
BW Unknown
N
<500
BW>=500 GA >=24Y
<24
GA Unknown
Imputation II: Infant Deaths
GA>=31 BW>=1500Y
NGA>=22 Y
500<=BW<1500
BW Unknown
N
<500
N / A
GA Unknown
What is PPOR Analysis?
Analytic Phases of PPOR Analytic Phases of PPOR
Phase 1Phase 1: Identifies populations and periods of risk with the largest excess mortality.
Phase 2Phase 2: Explains why the excess deaths occurred.
PPOR Maps Fetal & Infant Deaths
Age at Death
Birth
weig
ht
500-1499 g
1500+ g
Fetal
(24+
wks
)
Neonat
al
Postneo
natal
1 2 3
54 6
PPOR Maps Fetal & Infant Deaths
500-1499 g
1500+ g
Fetal Death Neonatal
Post- neonatal
Maternal Health/ Prematurity
Maternal Care
Newborn Care
Infant Health
Birth
weig
ht
Age at Death
PPOR is about ACTION(each period of risk is associated with a set of possible areas for action)
Maternal Health/
Prematurity
Maternal Care
Newborn Care
Infant Health
Preconception Health Health Behaviors Perinatal Care
Prenatal Care High Risk Referral Obstetric Care
Perinatal Management Neonatal Care Pediatric Surgery
Sleep Position Breast Feeding Injury Prevention
PPOR Map of Feto-Infant Deaths
83 Fetal Deaths are sorted into two periods of risk
Urban County, All Races2000-2002
35 Fetal DeathsMaternal Health/ Prematurity
48 Maternal
Care (fetal deaths)
PPOR Map of Feto-Infant Deaths
Of the 23,199 Infants born alive, 153 died. These are sorted into three periods of risk
Urban County, All Races2000-2002
62 Infant DeathsMaternal Health/ Prematurity
(live births)
44 Newborn
Care (live births)
47Infant Health
(live births)
PPOR Map of Feto-Infant Deaths
236 Feto-Infant Deaths
Urban County, All Races2000-2002
97Maternal Health/ Prematurity
(35 fetal deaths, 62 live births)
48 Maternal
Care (fetal deaths)
44 Newborn
Care (live births)
47Infant Health
(live births)
PPOR ANALYTIC METHODS Steps of Phase 1
Define study population
Restrict study population by birthweight and gestational age
Calculate numbers and rates for the feto-infant mortality map
Compare different time periods, subpopulations and geographic areas
Steps of Phase 1 Defining the Study Population Include mothers who are RESIDENTS
of the target area at the time of the baby’s birth.
Define the baby’s race/ethnicity according to the mother’s.
Include multiple gestations. Include congenital anomalies.
PPOR Map of Feto-Infant Deaths
23,199 live births
153 died as infants
83 fetal deaths
Denominator is 23,199 + 83 = 23,282
Urban County, All Races2000-2002
97Maternal Health/ Prematurity
(35 fetal deaths, 62 live births)
48 Maternal
Care (fetal deaths)
44 Newborn
Care (live births)
47Infant Health
(live births)
Calculating Feto-Infant Mortality Rate
4.2 + 2.1 + 1.9 + 2.0
= 10.1
Period rates add up to overall rate (except for round-off error)
Urban County, All Races2000-2002
2.1 Maternal
Care
1.9 Newborn
Care
2.0Infant Health
Maternal Health/ PrematurityRate=deaths x 1,000 ÷ births =97 deaths x 1,000 ÷ 23,282
= 4.2
White non-Hispanic
3.1
2.0 1.9 1.6
White Fetal-Infant
Rate = 8.6 (N=16,045)
Black non-Hispanic
2.4 4.02.4
8.8
Black Fetal-Infant
Rate =17.6 (N=3,291)
PPOR Map of Feto- Infant Mortality Urban County, By Race, 2000-2002(N=number of live births and fetal deaths)
STOP HERE ANALYTIC EXERCISE CALCULATE RATES
PPOR ANALYTIC METHODS More Phase 1 Steps:
“THE GAPS”
Select reference population Calculate excess mortality rates and
numbers of deaths Identify excess mortality gaps
PPOR Redefines Disparities, Estimates “Opportunity” Gap
ASK: Which women/infants have the ""best"best" outcomes?
ASSUMEASSUME: allall infants can have similar “best” outcomes
CHOOSECHOOSE: a comparisoncomparison groupgroup(s) (‘reference group’)(s) (‘reference group’) who already has achieved “best” outcomes
COMPARECOMPARE: fetal-infant mortality rates in your targettarget group with those of the comparison group(s)
CALCULATECALCULATE: excessexcess deaths (= target – comparison groups). This is your community’s “Opportunity Gap“Opportunity Gap..””
Reference Groups
Choose an easily defined optimal group •At least 15% of the population•At least 60 deaths•Acceptable to the community
U.S. National Reference Group:•20 or more years of age•13 or more years of education•Non-Hispanic white women
USA Reference Group 1998-2000• Defined by maternal characteristics
– 20 or more years of age– 13 or more years of education– Non-Hispanic white women– residents of the US at the time of baby’s
birth
2.2
1.5 1.1 1.0
Total Fetal-Infant Mortality Rate = 5.9
Calculating ExcessCalculating Excess RatesRates Overall population Urban County, 2000-2002
(external reference group)
Urban County
Maternal Health/
Prematurity
Maternal Care
Newborn Care
Infant
Health
Fetal-Infant Mortality
all 4.2 2.1 1.9 2.0 10.1
USA Reference
Group
Maternal Health/
Prematurity
Maternal Care
Newborn Care
Infant
Health
Fetal-Infant Mortality
2.2 1.5 1.1 1.0 5.9
Excess Mortality
Rate
Maternal Health/
Prematurity
Maternal Care
Newborn Care
Infant
Health
Fetal-Infant Mortality
By Subtraction 2.0 0.6 0.8 1.0 4.3
____________________________________________________________
Feto-Infant Mortality Rates Racial/Ethnic subgroups of Urban County, 2000-2002
(external reference group)Racial Groups
Maternal Health/
Prematurity
Maternal Care
Newborn Care
Infant Health
Overall Feto-Infant
Mortality
White, non-Hispanic
3.1 2.0 1.9 1.6 8.6
Black, non-Hispanic
8.8 2.4 2.4 4.0 17.6
Hispanic and other races
4.6 2.0 1.3 2.3 10.2
External Reference Group
2.2 1.5 1.1 1.0 5.9
ExcessExcess Feto-Infant Mortality RatesBased on USA 1998-2000 reference group
Racial/Ethnic Groups
Maternal Health/
Prematurity
Maternal Care
Newborn Care
Infant Health
Feto-Infant Mortality
White, non-Hispanic 0.9 0.5 0.8 0.6 2.8
Black, non-Hispanic 6.6 0.9 1.3 3.0 11.8
Other Races 2.4 0.5 0.2 1.3 4.4
All 2.0 0.6 0.8 1.0 4.3
CALCULATING EXCESS CALCULATING EXCESS NUMBERNUMBER OF DEATHS OF DEATHSFROM Fetal-Infant Mortality Rates
using External Comparison Group Urban County, 2000-2002
Racial/ Ethnic GroupExcess
Mortality Rate
Live Births and Fetal
deathsMultiply
Number of Excess Deaths
White Non-Hispanic 2.8 16,0452.8*16,045
1,000=45
Black Non-Hispanic 11.8 3,29111.8*3,291
1,000=39
Other Race 4.43,947 4.4*3,947
1,000=17
All4.3 23,282
4.3*23,2821,000
=101
Urban County by RaceUrban County by Race 2000-2002 estimated Excess Number of Deaths
based on external comparison group
Racial/Ethnic Groups
Maternal Health/
Prematurity
Maternal Care
Newborn Care
Infant Health
Feto-Infant Mortality
White, non-Hispanic 14 8 13 10 45
Black, non-Hispanic 22 3 4 10 39
Other Races 9 2 1 5 17
All 46 13 18 25 101
ANALYTIC EXERCISECALCULATE EXCESS MORTALITY AND
ESTIMATE EXCESS NUMBER OF DEATHS
Feto-Infant Mortality Rates in the Internal Comparison Group
(Best Outcomes in Urban County)Urban County, 2000-2002
2.4
2.2 1.8 1.0
Total Fetal-Infant Mortality Rate = 7.4
• Defined by maternal characteristics– 20 or more years of age– 13 or more years of education– Non-Hispanic White women– Residents of Urban County at time of
baby’s birth
ExcessExcess (Internal) (Internal) Fetal-Infant Mortality Rates
Overall population Urban County, 2000-2002
Urban County
Maternal Health/
Prematurity
Maternal Care
Newborn Care
Infant
Health
Fetal-Infant Mortality
4.2 2.1 1.9 2.0 10.1
Internal Reference
Group
Maternal Health/
Prematurity
Maternal Care
Newborn Care
Infant
Health
Fetal-Infant Mortality
2.4 2.2 1.8 1.0 7.4
Excess Mortality
Rate
Maternal Health/
Prematurity
Maternal Care
Newborn Care
Infant
Health
Fetal-Infant Mortality
By Subtraction 1.7 -0.1 0.1 1.0 2.7
____________________________________________________________
Fetal-Infant Mortality Rates Urban County, by Race,
Internal Comparison Group 2000-2002Racial Groups
Maternal Health/
Prematurity
Maternal Care
Newborn Care
Infant Health
Overall Feto-Infant
Mortality
White, non-Hispanic
3.1 2.0 1.9 1.6 8.6
Black, non-Hispanic
8.8 2.4 2.4 4.0 17.6
Hispanic and other races
4.6 2.0 1.3 2.3 10.2
Internal Reference Group 2.4 2.2 1.8 1.0 7.4
Urban County by RaceUrban County by Race 2000-2002 Excess Fetal-Infant Mortality Rates
based on internal comparison group
Racial/Ethnic Groups
Maternal Health/
Prematurity
Maternal Care
Newborn Care
Infant Health
Feto-Infant Mortality
White, non-Hispanic 0.7 -0.2 0.1 0.6 1.2
Black, non-Hispanic 6.4 0.2 0.6 3.0 10.2
Other Races 2.2 -0.2 -0.5 1.3 2.8
All 1.7 -0.1 0.1 1.0 2.7
Urban County by Race 2000-2002 Estimated Excess Number of Deaths
based on internal comparison group
Racial/Ethnic Groups
Maternal Health/
Prematurity
Maternal Care
Newborn Care
Infant Health
Feto-Infant Mortality
White, non-Hispanic 10 -3 1 10 19
Black, non-Hispanic 21 1 2 10 33
Other Races 8 -1 -2 5 11
All 40 -3 2 24 63
• Builds data and epi capacity
• Promotes effective data use
• Strengthens essential partnerships
• Fosters integration with other key efforts
• Encourages evidence-based interventions
• Helps leverage resources
• Enables systems change for perinatal health
PPOR is about impactimpact and resultsresults:
• Please remember to turn in your evaluations !
Perinatal Periods of Risk: For More Information:
www.citymatch.org
By looking at the numbers in a new way, we can finally understand fetal/infant mortality and its common causes. Only through understanding can we take steps to ensure every child gets a chance at life.
The Perinatal Periods of Risk Approach
CityMatCH Training August 25, 2007
Denver, Coloradowww.citymatch.org
Phase 1 Analytic Methods