Combining health and social protection measures to reach the ultra ...

Decision-makingwas prior to 2001, a time series of annual life tables(adjusted if the registration level was incomplete) between1985 and the latest available year was used to projectlevels of child and adult mortality for 2001. For smallcountries with populations of less than 500 000, movingaverages were used to smooth the time series. Projectedvalues of child and adult mortality were then applied to amodified logit life table model 6 , using the most recentnational data as the standard, to predict the full life tablefor 2001, and HIV/AIDS and war deaths were added tototal mortality rates for 2001 where necessary. Thismethod was applied for 40 countries using a total of 711country-years of death registration data.✜ Countries with other information on levels of child andadult mortality. For 37 countries, estimated levels ofchild and adult mortality were applied to a modified logitlife table model 6 , using a global standard, to estimate thefull life table for 2001, and HIV/AIDS deaths and wardeaths were added to total mortality rates as necessary.For most of these countries, data on levels of adultmortality were obtained from death registration data,official life tables, or mortality information derived fromother sources such as censuses and surveys. The allcausemortality envelope for China was derived from atime series analysis of deaths for every household inChina reported in the 1982, 1990, and 2000 censuses.The extent of underreporting of deaths in the 2000census was estimated at about 11.3% for males and18.1% for females 1 . The all-cause mortality envelope forIndia was derived from a time series analysis of agespecificdeath rates from the sample registration systemafter correction for underregistration (88%completeness) 8 .✜ Countries with information on levels of child mortalityonly. For 55 countries, 42 of them in sub-SaharanAfrica, no information was available on levels of adultmortality. Based on the predicted level of child mortalityin 2001, the most likely corresponding level of adultmortality (excluding HIV/AIDS deaths where necessary)was selected, along with uncertainty ranges, based onregression models of child versus adult mortality asobserved in a set of almost 2000 life tables judged to beof good quality 2,6 . These estimated levels of child andadult mortality were then applied to a modified logit lifetable model, using a global standard, to estimate the fulllife table in 2001, and HIV/AIDS deaths and war deathswere added to total mortality rates as necessary.Evidence on adult mortality in sub-Saharan Africancountries remains limited, even in areas with successfulchild and maternal mortality surveys.Classification of causes of disease and injuryDisease and injury causes of death and of burden of diseasewere classified using the same tree structure as in the originalGBD study 7 . The first level of disaggregation comprises thefollowing three broad cause groups:✜ Group I: communicable, maternal, perinatal, andnutritional conditions;✜ Group II: noncommunicable diseases;✜ Group III: injuries.Each group was then divided into major causesubcategories, for example, cardiovascular disease (CVD) andmalignant neoplasms (cancers) are two major causesubcategories of Group II. Beyond this level, two furtherdisaggregation levels were used, resulting in a completecause list of 135 categories of specific diseases and injuries.Group I causes of death consist of the cluster of conditionsthat typically decline at a faster pace than all-cause mortalityduring the epidemiological transition. In high-mortalitypopulations, Group I dominates the cause of death pattern,whereas in low-mortality populations, Group I accounts foronly a small proportion of deaths. The major causesubcategories are closely based on the ICD chapters with afew significant differences. Whereas the ICD classifies chronicrespiratory diseases and acute respiratory infections into thesame chapter, the GBD cause classification includes acuterespiratory infections in Group I and chronic respiratorydiseases in Group II. Note also that the Group I subcategoryof “causes arising in the perinatal period” relates to thecauses included in the corresponding ICD chapter, principallylow birth weight, prematurity, birth asphyxia, and birthtrauma, but does not include all causes of deaths occurringduring the perinatal period, such as infections, congenitalmalformations, and injuries. In addition, the GBD includesonly deaths among children born alive and does notestimate stillbirths.The GBD classification system does not include the ICDcategory “Symptoms, signs, and ill-defined conditions” as oneof the major causes of deaths. The GBD classification schemehas reassigned deaths assigned to this ICD category, as wellas some other codes used for ill-defined conditions, tospecific causes of death. This is important from theperspective of generating useful information to comparecause of death patterns or to inform health policy-making,because it allows unbiased comparisons of cause of deathpatterns across countries or regions.Deaths are categorically attributed to one underlying causeusing ICD rules and conventions. In some cases where theICD rules are ambiguous, the GBD 2001 follows theconventions used by the GBD 1990 study 7 . It should also benoted that a number of causes of death act as risk factors forother diseases. Total mortality attributable to such causesmay be substantially larger than the mortality estimates forthe cause in terms of ICD rules for underlying causes. Forexample, the GBD 2001 estimates that 960 000 deaths weredue to diabetes mellitus as an underlying cause, but whendeaths from CVD and renal failure attributable to diabetes areincluded, the global total of attributable deaths rises to almost3 million 9 . Other causes for which important components ofattributable mortality are included elsewhere in the GBDcause list include hepatitis B or C (attributable liver cancerand renal failure), unipolar or bipolar depressive disordersand schizophrenia (attributable suicide), and blindness(mortality attributable to blindness whether from infectious ornon-infectious causes).164 ✜ Global Forum Update on Research for Health Volume 4