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UNIVERSITY OF WASHINGTON
Neonatal, postneonatal, childhood, and under-5 mortality for 187 countries, 1970-2010: a systematic analysis of progress towards MDG4
May 24, 2010
Julie Rajaratnam
Outline
Background
Methods
Results
Implications
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Tracking Progress on MDG4
• Substantial investments through the DHS and MICS to collect improved data on child mortality.
• Recent sub-national studies and national surveys suggest child mortality may be declining more rapidly in recent years in sub-Saharan Africa than we thought.
• Inconsistencies from year to year and source to source in the measurement of trends in child mortality.
• Robust measurement essential for tracking progress and drawing meaningful inference from trends for policy formulation.
Opportunities for Improved Estimation of Levels and Trends in Child Mortality
• New surveys released since 2007.
• New methods published in PLoS Medicine to analyze summary birth histories with improved accuracy. For most recent time periods, the new methods reduce error by 53.3%.
• New data synthesis methods available with enhanced in-sample fit and out-of-sample predictive validity.
• Improved modeling strategies and data for assessing neonatal, postneonatal and childhood mortality.
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Outline
Background
Methods
Results
Implications
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Expanded Data Sources
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Empirical Measurements
Vital Registration 3549
Sample Registration Systems 53
Complete Birth Histories 1447
Summary Birth Histories 9870
Household Deaths 62
Country-Specific Surveys 10
Disease Surveillance Points 12
Murray, Laakso, Shibuya et al Original Database
1075
Reports and Publications 96
Total 16174
Methods for Child Mortality Data Synthesis
• Piece-wise linear regression, also called Spline regression
• Loess regression
• Gaussian Process Regression (GPR)
o Advantages
─ Directly captures observation specific sampling uncertainty and non-sampling variance
─ Closely tracks data where sampling and non sampling error is low, follows long-term patterns where data sources are more inconsistent
─ Provides coherent assessment of uncertainty at each point and correlation of uncertainty between time periods
─ Improved performance
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GPR Has Improved Performance
• We assessed performance of GPR three ways in an extensive analysis of predictive validity:
o how well it fits data in-sample,
o how well it predicts child mortality in a given year when a 20% random sample of the data are excluded, and
o how well it forecasts, by dropping the last 10 years of data for all countries with more than 20 years of observations.
• In all three tests, GPR has better performance than alternative methods.
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Gaussian process regression
• In-sample performanceo Median relative error (%) for the five methods by broad source
categories.
Method Survey Low/Middle Income VR High-Income VRGPR 6.0 6.9 1.0Loess - 2007 8.3 11.1 7.7Spline - 3 6.7 9.2 3.4Spline - 5 6.8 10.5 4.0Spline - 10 7.0 11.3 5.1
Gaussian process regression
• Withholding random 20% of data:
• Withholding the last 10 years of data in every country (forecasting):
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Method Mean Relative Error Median Relative ErrorGPR 17.7 10.9Loess - 2007 18.3 13.1Spline - 3 40.5 15.1Spline - 5 26.4 14.7Spline - 10 24.8 13.9
Method Mean Relative Error Median Relative ErrorGPR 11.0 7.3Loess - 2007 13.4 10.1Spline - 3 12.7 9.0Spline - 5 12.1 9.0Spline - 10 24.8 13.9
Neonatal, Postneonatal, Childhood Model
• Fewer data sources provide information on the breakdown of under-five deaths by month of death required to measure NN, PNN or CHD rates.
• Data (147 countries):
o 1234 VR country-years
o 526 DHS complete birth history country-years
• We estimate a hierarchical model relating the probability of an under-5 death occurring during the NN, PNN or CHD period to the level of under-5 mortality using a random intercept and slope.
• We tested multiple specifications for this model and used the model with the highest predictive validity.
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Predictive Validity for Neonatal, Postneonatal, Childhood Model
Design Age Mean Relative Error Median Relative Error
In Sample Neonatal 9.3% 6.2%
Post-neonatal 10.9% 8.0%
Child 11.4% 7.8%
Dropping 20% of data Neonatal 9.8% 6.7%
Post-neonatal 11.8% 8.7%
Child 11.9% 8.1%
Dropping 20% of countries
Neonatal 11.4% 7.1%
Post-neonatal 12.9% 9.1%
Child 14.3% 8.9%
Dropped last 10 years Neonatal 14.4% 11.4%
Post-neonatal 21.0% 15.1%
Child 19.2% 13.3%
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Outline
Background
Methods
Results
Implications
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Country Examples: Norway
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Country Examples: El Salvador
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Country Examples: Laos
Country Examples: Liberia
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Global Under Five Deaths 1970-2010
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Global Neonatal, Postneonatal,and Childhood Mortality Rates 1970-2010
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Under-Five Death Rates by RegionGroup A
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Under-Five Death Rates by RegionGroup B
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Under-Five Death Rates by RegionGroup C
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Under-Five Death Rates by RegionGroup D
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Under-Five Mortality Rate in 2010
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Annual Rate of Decline in U5 1990-2010
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Regional Rates of Decline NN, PNN and CHD 1990-2010
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Accelerating Progress on U5
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Developing countries on track to achieve MDG 4
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Country Rate of decline (%) Country Rate of decline (%)
Maldives 9.21 Syrian Arab Republic 5.11
United Arab Emirates 8.43 Algeria 4.99
Oman 6.92 Bhutan 4.92
Turkmenistan 6.65 Cuba 4.88
Viet Nam 6.4 Armenia 4.84
Sri Lanka 6.28 Thailand 4.83
Egypt 6.2 Brazil 4.81
Malaysia 5.85 Bahrain 4.74
Tunisia 5.69 China 4.72
El Salvador 5.64 Mexico 4.63
Lebanon 5.62 Bangladesh 4.57
Peru 5.42 Honduras 4.57
Libyan Arab Jamahiriya 5.34 Barbados 4.55
Nepal 5.33 Costa Rica 4.5
Chile 5.16 Turkey 4.47
Mongolia 5.15
• Birth transferenceo Does not have a great
effect on the estimates
• HIV/AIDSo Simulation studies suggest
that in countries with sero-prevalence of 20% under-5 mortality may be under-estimated by 10 per 1000 to over-estimated by 6 per 1000.
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Limitations
Outline
Background
Methods
Results
Implications
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Summary
• Analysis of 16,174 measurements for 187 countries from 1970 to 2010 show that under-5 deaths have dropped from 16 million in 1970 to 7.7 million in 2010.
• Annual rate of decline in developing countries during MDG4 period is 2.1%; below the target of 4.4% per year.
• In 1990, 12 countries had under-5 death rates over 200 per 1000; now there are none.
• Progress has been slowest in sub-Saharan Africa, but in 34 countries in the region the rate of decline is faster in 2000 to 2010 compared to 1990 to 2000.
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Learning from Success Stories
• Across and within the 21 regions, there is marked variability in the pace of decline.
• Next step for the research agenda should be to examine what are the policy determinants that may have contributed to faster or slower rates of decline in under-5 mortality.
• Rapid declines in under-5 death rates are possible; 66 countries in the world have decreased child mortality by 30% in a period of 5 years.
• Such rapid declines provide hope that accelerated progress is possible.
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