Global mortality landscape November 1, 2010 Christopher J.L. Murray Institute Director
Outline <ul><li>Overview of data for all-cause mortality estimation </li></ul><ul><li>Child estimates </li></ul><ul><li>Ad...
<ul><li>Most developing countries do not have vital registration systems that capture all deaths  </li></ul><ul><li>Altern...
<ul><li>We focus time on all-cause mortality measurement because it is a key input to measuring any cause of adult female ...
Mortality estimation at IHME <ul><li>Goals: </li></ul><ul><ul><li>Identify all available data sources </li></ul></ul><ul><...
Mortality Estimation
GBD Epidemiological Regions
New Tools for Mortality Data Analysis
New Tools for Synthesizing Data Sources
<ul><li>Gaussian process regression: used in adult and child models </li></ul><ul><ul><li>Allows for more flexibility in f...
Outline <ul><li>Overview of data for all-cause mortality estimation </li></ul><ul><ul><li>Data for the estimation of child...
Data Empirical Measurements Outliers Vital Registration 3549 77 Sample Registration Systems 53 1 Complete Birth Histories ...
Neonatal, Post-neonatal, Childhood Model <ul><li>Fewer data sources provide information on the breakdown of under-five dea...
Predictive Validity for Neonatal, Post-neonatal, Childhood Model Design Age Mean Relative Error Median Relative Error In S...
Outline <ul><li>Overview of data for all-cause mortality estimation </li></ul><ul><ul><li>Data for the estimation of child...
Systematic search of official, survey and published literature Rajaratnam et al, Lancet 2010
Assessing completeness of death reporting <ul><li>For each vital registration data point, census or survey recall of death...
 
 
 
 
 
 
 
 
Sibling History Data Needs to be Corrected for Survivor Bias <ul><li>DHS sibling histories provide underestimates in most ...
Outline <ul><li>Overview of data process for all-cause mortality estimation </li></ul><ul><li>Child estimates </li></ul><u...
Under-5 mortality by GBD region
Global under-5 death numbers compared to other sources
Global trends in neonatal, post-neonatal and child mortality rates
Under-5 mortality rate by GBD region
Under-5 mortality rate, 2010
Annualized rate of decline in U5MR 1990-2010
Annualized percent decline in under-5 mortality by Region
Key findings <ul><li>Global under-five mortality has dropped from 11.9 million in 1990 to 7.9 million in 2008, a 34% reduc...
Outline <ul><li>Overview of data process for all-cause mortality estimation </li></ul><ul><li>Child estimates </li></ul><u...
Adult Mortality  Global trend in adult mortality, 1970-2010
Trend in adult mortality by GBD region
Adult Mortality, 2010 Women Men
Annualized rate of decline in adult mortality, 1970-2010  Women Men
Countries with the lowest risks of adult mortality in 1970 and 2010, by sex
Key findings <ul><li>Trends in adult mortality differ by country and sex </li></ul><ul><li>IHME adult mortality estimates ...
Outline <ul><li>Overview of data process for all-cause mortality estimation </li></ul><ul><li>Child estimates </li></ul><u...
Outline <ul><li>Overview of data process for all-cause mortality estimation </li></ul><ul><li>Child estimates </li></ul><u...
Model Life Table Systems <ul><li>What we want: a full life table (age specific mortality rates) for a population where we ...
Model Life Table Systems <ul><li>Model Life Table Systems are built on the observation that age specific probabilities of ...
Establishing the Standard Life Table <ul><li>Use 5q0 and 45q15 (and other ‘entry-parameters’) to identify a life table fro...
Basic mechanics <ul><li>Transform 5q0 and 45q15 to the life table indicators which will be related to the standard life ta...
Current Method: Establishing the standard life table <ul><li>Expanded database of empirical life tables </li></ul><ul><ul>...
Current Method: Specification of Model <ul><li>Two-pronged approach </li></ul><ul><li>1) Countries with abundant data </li...
Conclusions <ul><li>Advantages of the current model: </li></ul><ul><li>Built upon a database with over 8,000 empirical lif...
Outline <ul><li>Overview of data process for all-cause mortality estimation </li></ul><ul><li>Child estimates </li></ul><u...
Global Maternal Deaths
Global Maternal Deaths Year Number of maternal deaths (Uncertainty interval) 1980 526,300 (446,400 – 629,600) 1990 441,500...
Births by Region, 1980-2008
Global Maternal Mortality Ratio
Maternal Deaths by Region, 1980-2008
Regional trends in the MMR
Regional trends in the MMR
MMR with and without HIV
MMR per 100,000 live births, 2008
Top 21 countries: maternal deaths Order Country Deaths in 1000s (UI) Deaths (%) Cumulative % Births (%) Cumulative % 1 Ind...
Annualized Rate of Decline in MMR,  1990 to 2008
Annualized Rate of Decline in MMR, excluding HIV, 1990 to 2008
Gaining Ground <ul><li>Global maternal deaths down to 342,900 in 2008 </li></ul><ul><li>Global trend is a 1.4% decline per...
Progress Undocumented But Not Unexpected <ul><li>Global total fertility rate has dropped from 3.70 in 1980 to 2.56 in 2008...
Adverse Impact of HIV <ul><li>Progress on reducing maternal mortality would have been much greater in the absence of HIV, ...
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  • Mention predictive validity testing
  • Mention predictive validity testing
  • DATA ARRANGED BY CHILD/ADULT
  • The mortality work group successfully published three methods papers in PLoS Medicine in April 2010, exceeding the plans delineated for FY10. The first, Measuring Under-Five Mortality: Validation of New Lost-Cost Methods , describes significantly improved methods for estimating under-five mortality using summary birth histories. It introduces a new model which enables more accurate and timely estimates for child mortality in systems without complete vital registration data, and complete birth history data. This model will also provide more accurate sub-national child mortality estimates when applied to country census data.   The second article, What Can We Conclude from Death Registration? Improved Methods for Evaluating Completeness , systematically evaluates the many variants of the standard death distribution methods used to assess completeness of vital registration systems. It presents three variants of the death distribution methods that perform the best in most situations. This newly developed model has been put to use in generating the adult mortality estimates mentioned above. The third paper, Measuring Adult Mortality Using Sibling Survival: A New Analytical Method and New Results for 44 Countries, 1974-2006, presents a new method which improves estimation of mortality rates directly from empirical data sources for many countries. The model produces much more plausible estimates of adult mortality and will be highly applicable to all large nationally representative survey programs.
  • Mention predictive validity testing
  • 545 surveys with summary birth history microdata or tabulated data 256 surveys with complete birth history microdata DDM on household deaths
  • Logit transformation
  • maternal mortality sri lanka global mortality landscape_murray_110110_ihme

    1. 1. Global mortality landscape November 1, 2010 Christopher J.L. Murray Institute Director
    2. 2. Outline <ul><li>Overview of data for all-cause mortality estimation </li></ul><ul><li>Child estimates </li></ul><ul><li>Adult estimates </li></ul><ul><li>Country 45q15 results </li></ul><ul><li>Age-specific all-cause death counts </li></ul><ul><li>Maternal estimates </li></ul>
    3. 3. <ul><li>Most developing countries do not have vital registration systems that capture all deaths </li></ul><ul><li>Alternative methods have evolved to track all-cause mortality in these countries: </li></ul><ul><li>Correcting incomplete vital registration systems using “death distribution methods” </li></ul><ul><li>Using sample registration systems with or without correction for incompleteness </li></ul><ul><li>Census data on deaths in the last 12 months </li></ul><ul><li>Survey data on sibling survival </li></ul>Measuring Adult Mortality Can Be Challenging
    4. 4. <ul><li>We focus time on all-cause mortality measurement because it is a key input to measuring any cause of adult female mortality especially maternal mortality. </li></ul><ul><li>A major difference between WHO and IHME estimation of maternal mortality is due to different assessments of adult female reproductive-aged mortality </li></ul>Levels of Adult Female Mortality Are a Key Input to Measuring Maternal Mortality
    5. 5. Mortality estimation at IHME <ul><li>Goals: </li></ul><ul><ul><li>Identify all available data sources </li></ul></ul><ul><ul><li>Correct these data sources for known biases using the best methods </li></ul></ul><ul><ul><li>Apply a modeling algorithm that allows for the synthesis of multiple data sources </li></ul></ul><ul><ul><li>Provide uncertainty estimates </li></ul></ul>
    6. 6. Mortality Estimation
    7. 7. GBD Epidemiological Regions
    8. 8. New Tools for Mortality Data Analysis
    9. 9. New Tools for Synthesizing Data Sources
    10. 10. <ul><li>Gaussian process regression: used in adult and child models </li></ul><ul><ul><li>Allows for more flexibility in functional form of mortality over time </li></ul></ul><ul><ul><li>Informed by prior beliefs, data, and uncertainty </li></ul></ul><ul><ul><li>Better captures both sampling and nonsampling uncertainty in empirical data sources </li></ul></ul><ul><li>Spatial-temporal regression: used with adult model only </li></ul><ul><ul><li>Borrows strength from other related observations from another time point or related area </li></ul></ul><ul><ul><li>The method (a two-stage approach): </li></ul></ul><ul><ul><ul><li>Runs a linear regression </li></ul></ul></ul><ul><ul><ul><li>Smoothes the residuals over space and time </li></ul></ul></ul><ul><ul><ul><li>Adds smoothed residuals back into the first stage prediction </li></ul></ul></ul>New Tools for Synthesizing Data Sources: Methods
    11. 11. Outline <ul><li>Overview of data for all-cause mortality estimation </li></ul><ul><ul><li>Data for the estimation of child mortality </li></ul></ul><ul><ul><li>Data for the estimation of adult mortality </li></ul></ul><ul><li>Child estimates </li></ul><ul><li>Adult estimates </li></ul><ul><li>Country 45q15 results </li></ul><ul><li>Age-specific all-cause death counts </li></ul><ul><li>Maternal estimates </li></ul>
    12. 12. Data Empirical Measurements Outliers Vital Registration 3549 77 Sample Registration Systems 53 1 Complete Birth Histories 1447 8 Summary Birth Histories 9870 685 Household Deaths 62 17 Country-Specific Surveys 10 5 Disease Surveillance Points 12 0 Murray, Laakso, Shibuya et al Original Database 1075 241 Reports and Publications 96 0 Total 16174 1034
    13. 13. Neonatal, Post-neonatal, Childhood Model <ul><li>Fewer data sources provide information on the breakdown of under-five deaths by month of death required to measure NN, PNN or CHD rates. </li></ul><ul><li>Data (147 countries): </li></ul><ul><ul><li>1234 VR country-years </li></ul></ul><ul><ul><li>526 DHS complete birth history country-years </li></ul></ul><ul><li>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. </li></ul><ul><li>We tested multiple specifications for this model and used the model with the highest predictive validity. </li></ul>
    14. 14. Predictive Validity for Neonatal, Post-neonatal, 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%
    15. 15. Outline <ul><li>Overview of data for all-cause mortality estimation </li></ul><ul><ul><li>Data for the estimation of child mortality </li></ul></ul><ul><ul><li>Data for the estimation of adult mortality </li></ul></ul><ul><li>Child estimates </li></ul><ul><li>Adult estimates </li></ul><ul><li>Country 45q15 results </li></ul><ul><li>Age-specific all-cause death counts </li></ul><ul><li>Maternal estimates </li></ul>
    16. 16. Systematic search of official, survey and published literature Rajaratnam et al, Lancet 2010
    17. 17. Assessing completeness of death reporting <ul><li>For each vital registration data point, census or survey recall of deaths in recent time periods, and sample registration data, evaluated completeness using new death distribution methods. </li></ul><ul><li>Assessment of completeness for adults takes into account the results of three different death distribution methods and the independently assessed completeness of the VR system for child mortality. </li></ul><ul><li>Completeness of adult VR is better than previously believed in many middle-income countries. </li></ul>
    18. 26. Sibling History Data Needs to be Corrected for Survivor Bias <ul><li>DHS sibling histories provide underestimates in most cases of adult mortality due to survivor bias and recall bias. </li></ul><ul><li>We re-analyzed all sibling history data to take into account these corrections. </li></ul><ul><li>Corrections change mortality rate on average by more than 30% </li></ul>Obermeyer et al PLoS Medicine
    19. 27. Outline <ul><li>Overview of data process for all-cause mortality estimation </li></ul><ul><li>Child estimates </li></ul><ul><li>Adult estimates </li></ul><ul><li>Country 45q15 results </li></ul><ul><li>Age-specific all-cause death counts </li></ul><ul><li>Maternal estimates </li></ul>
    20. 28. Under-5 mortality by GBD region
    21. 29. Global under-5 death numbers compared to other sources
    22. 30. Global trends in neonatal, post-neonatal and child mortality rates
    23. 31. Under-5 mortality rate by GBD region
    24. 32. Under-5 mortality rate, 2010
    25. 33. Annualized rate of decline in U5MR 1990-2010
    26. 34. Annualized percent decline in under-5 mortality by Region
    27. 35. Key findings <ul><li>Global under-five mortality has dropped from 11.9 million in 1990 to 7.9 million in 2008, a 34% reduction in 28 years. U5 death number is estimated to be 7.7 million in 2010 </li></ul><ul><li>Majority of the under-five deaths occurred in developing countries. Around 87% of the U5 deaths occurred in South Asia and Sub-Saharan Africa in 2008 </li></ul><ul><li>Under-five mortality rates are declining among all 21 GBD regions. Accelerated decline is observed in 13 of the 21 GBD regions, including Sub-Saharan Africa </li></ul><ul><li>Trends of change in under-five mortality at country level differ within GBD regions </li></ul>
    28. 36. Outline <ul><li>Overview of data process for all-cause mortality estimation </li></ul><ul><li>Child estimates </li></ul><ul><li>Adult estimates </li></ul><ul><li>Country 45q15 results </li></ul><ul><li>Age-specific all-cause death counts </li></ul><ul><li>Maternal estimates </li></ul>
    29. 37. Adult Mortality Global trend in adult mortality, 1970-2010
    30. 38. Trend in adult mortality by GBD region
    31. 39. Adult Mortality, 2010 Women Men
    32. 40. Annualized rate of decline in adult mortality, 1970-2010 Women Men
    33. 41. Countries with the lowest risks of adult mortality in 1970 and 2010, by sex
    34. 42. Key findings <ul><li>Trends in adult mortality differ by country and sex </li></ul><ul><li>IHME adult mortality estimates are quite different from those provided by United Nations Population Division </li></ul><ul><li>The new method provides estimates of adult mortality for countries without empirical data </li></ul><ul><li>Annual rate of change in adult mortality has wide range. Rapid decline in adult mortality is possible and has been observed in many countries </li></ul>
    35. 43. Outline <ul><li>Overview of data process for all-cause mortality estimation </li></ul><ul><li>Child estimates </li></ul><ul><li>Adult estimates </li></ul><ul><li>Country 45q15 results </li></ul><ul><li>Age-specific all-cause death counts </li></ul><ul><li>Maternal estimates </li></ul>
    36. 44.
    37. 45.
    38. 46.
    39. 47.
    40. 48.
    41. 49.
    42. 50.
    43. 51.
    44. 52.
    45. 53.
    46. 54.
    47. 55.
    48. 56. Outline <ul><li>Overview of data process for all-cause mortality estimation </li></ul><ul><li>Child estimates </li></ul><ul><li>Adult estimates </li></ul><ul><li>Country 45q15 results </li></ul><ul><li>Age-specific all-cause death counts </li></ul><ul><li>Maternal estimates </li></ul>
    49. 57. Model Life Table Systems <ul><li>What we want: a full life table (age specific mortality rates) for a population where we only know 5q0, 45q15 and HIV seroprevalence </li></ul><ul><li>What we have: a set of empirical life tables of high quality from other populations </li></ul>
    50. 58. Model Life Table Systems <ul><li>Model Life Table Systems are built on the observation that age specific probabilities of death from two life tables from similar populations are linearly related (after some transformation) </li></ul>
    51. 59. Establishing the Standard Life Table <ul><li>Use 5q0 and 45q15 (and other ‘entry-parameters’) to identify a life table from a population with similar mortality situation within your empirical data set </li></ul><ul><ul><li>The selected empirical life table is referred to as the “standard” life table </li></ul></ul><ul><ul><li>For example, you might select the 1934 life table if you wished to obtain a life table for 1935 </li></ul></ul><ul><li>One could also select a set of empirical life tables and average them together to get a standard life table </li></ul>
    52. 60. Basic mechanics <ul><li>Transform 5q0 and 45q15 to the life table indicators which will be related to the standard life table </li></ul><ul><li>Relate observed life table indicators to the standard life table by estimating a linear equation </li></ul><ul><li>Use the rest of the age-specific probabilities from the standard life table and the linear equation to then obtain the whole life table for the country-year of interest </li></ul>
    53. 61. Current Method: Establishing the standard life table <ul><li>Expanded database of empirical life tables </li></ul><ul><ul><li>A total of 8,682 country-years including 526 life tables from Africa and Asia (in addition to Asia/High Income countries) </li></ul></ul><ul><li>Improved matching process to identify life tables from similar populations </li></ul><ul><ul><li>For countries where an empirical life table from the same country is available within a 15-year radius in the database, use the observed life tables as standard </li></ul></ul><ul><ul><li>For all other countries, use entry parameters: 5q0, 45q15 to match life tables out of the database (priorities are given to life tables from the same country/GBD region) </li></ul></ul>
    54. 62. Current Method: Specification of Model <ul><li>Two-pronged approach </li></ul><ul><li>1) Countries with abundant data </li></ul><ul><ul><li>Age specific models that predict the difference in mortality between the country-year of interest and the standard based on differences in 5q0 and 45q15 are developed </li></ul></ul><ul><ul><li>Models are then used with single-year closest to the year of interest to predict the full life table </li></ul></ul><ul><li>2) Countries with limited data </li></ul><ul><ul><li>Age specific models that predict the difference in mortality between the country-year of interest and the standard based on differences in 5q0 and 45q15 are developed </li></ul></ul><ul><ul><li>Models are used to predict mortality in the absence of HIV </li></ul></ul><ul><ul><li>Rate of change models are used to add on HIV component of mortality </li></ul></ul>
    55. 63.
    56. 64. Conclusions <ul><li>Advantages of the current model: </li></ul><ul><li>Built upon a database with over 8,000 empirical life tables </li></ul><ul><li>Improved predictive validity </li></ul><ul><li>More versatile </li></ul><ul><li>Provides plausible estimates for CYs affected by HIV/AIDS </li></ul><ul><li>Provides age specific mortality rates that follow the trends in 5q0 and 45q15 </li></ul>
    57. 65. Outline <ul><li>Overview of data process for all-cause mortality estimation </li></ul><ul><li>Child estimates </li></ul><ul><li>Adult estimates </li></ul><ul><li>Country 45q15 estimates </li></ul><ul><li>Age-specific all-cause death counts </li></ul><ul><li>Maternal estimates </li></ul><ul><ul><li>The rest of the workshop will offer an opportunity to discuss in great detail the data and methods used to arrive at the following estimates </li></ul></ul>
    58. 66. Global Maternal Deaths
    59. 67. Global Maternal Deaths Year Number of maternal deaths (Uncertainty interval) 1980 526,300 (446,400 – 629,600) 1990 441,500 (376,200 – 535,100) 2000 417,200 (365,700 – 479,200) 2008 342,900 (302,100 – 394,300)
    60. 68. Births by Region, 1980-2008
    61. 69. Global Maternal Mortality Ratio
    62. 70. Maternal Deaths by Region, 1980-2008
    63. 71. Regional trends in the MMR
    64. 72. Regional trends in the MMR
    65. 73. MMR with and without HIV
    66. 74. MMR per 100,000 live births, 2008
    67. 75. Top 21 countries: maternal deaths Order Country Deaths in 1000s (UI) Deaths (%) Cumulative % Births (%) Cumulative % 1 India 68.3 (41.6-106.2) 19.9 19.9 19.7 19.7 2 Nigeria 36.7 (22.4-57.0) 10.7 30.6 4.4 24.1 3 Pakistan 20.1 (12.3-31.3) 5.9 36.5 3.9 28.0 4 Afghanistan 20.0 (7.5-43.1) 5.8 42.3 0.9 28.9 5 Ethiopia 18.2 (11.1-28.8) 5.3 47.6 2.3 31.2 6 Congo, the Democratic Republic of the 15.4 (9.0-24.7) 4.5 52.1 2.1 33.3 7 Bangladesh 11.6 (6.7-18.7) 3.4 55.5 2.5 35.8 8 Indonesia 9.6 (5.6-16.0) 2.8 58.3 3.1 38.9 9 Tanzania, United Republic of 8.0 (4.8-12.8) 2.3 60.6 1.3 40.2 10 China 7.3 (6.4-8.3) 2.1 62.7 13.3 53.5 11 Malawi 6.8 (4.0-10.9) 2.0 64.7 0.4 53.9 12 Côte d'Ivoire 6.8 (4.1-10.8) 2.0 66.7 0.5 54.4 13 Kenya 6.2 (3.6-10.2) 1.8 68.5 1.1 55.5 14 Chad 5.3 (3.3-8.2) 1.5 70.0 0.4 55.9 15 Mozambique 5.2 (3.1-8.4) 1.5 71.5 0.6 56.5 16 Uganda 5.2 (3.1-8.2) 1.5 73.0 1.1 57.6 17 Cameroon 5.0 (2.8-8.1) 1.4 74.4 0.5 58.1 18 Niger 4.7 (3.0-7.3) 1.4 75.8 0.6 58.7 19 Angola 4.6 (1.8-9.9) 1.3 77.1 0.6 59.3 20 Sudan 4.0 (2.5-6.0) 1.2 78.3 0.9 60.2 21 Mali 3.6 (2.3-5.5) 1.1 79.4 0.4 60.6 All other countries (160) 70.3 (43.0-112.2) 20.5 100.0 39.3 100.0 Total   342.9 100.0 100.0 100.0 100.0
    68. 76. Annualized Rate of Decline in MMR, 1990 to 2008
    69. 77. Annualized Rate of Decline in MMR, excluding HIV, 1990 to 2008
    70. 78. Gaining Ground <ul><li>Global maternal deaths down to 342,900 in 2008 </li></ul><ul><li>Global trend is a 1.4% decline per year since 1990 </li></ul><ul><li>23 countries are on track to meet MDG 5, achieving an annual rate of decline of 5.5% </li></ul><ul><ul><li>Includes Egypt, Albania, Tunisia, El Salvador, Romania </li></ul></ul><ul><li>Other countries are achieving substantial progress </li></ul><ul><ul><li>Including China, Bolivia, Ecuador, Peru, Rwanda </li></ul></ul>
    71. 79. Progress Undocumented But Not Unexpected <ul><li>Global total fertility rate has dropped from 3.70 in 1980 to 2.56 in 2008 </li></ul><ul><li>Income per capita has been rising over the period, particularly in Asia and Latin America </li></ul><ul><li>Maternal education has been increasing as well </li></ul><ul><ul><li>In sub-Saharan Africa, the average years of schooling for women aged 25-44 rose from 1.5 years in 1980 to 4.4 years in 2008 </li></ul></ul><ul><li>The steady, slow rise in skilled birth attendance coverage may also have contributed </li></ul>
    72. 80. Adverse Impact of HIV <ul><li>Progress on reducing maternal mortality would have been much greater in the absence of HIV, especially in sub-Saharan Africa </li></ul><ul><li>Important implications for intervention policy </li></ul><ul><ul><li>Interventions for treating pregnant women with HIV would include antiretrovirals, not part of the set of interventions targeting HIV-negative women </li></ul></ul><ul><li>Critical to track HIV-related maternal mortality, but challenging in settings without vital registration </li></ul>
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