Epidemiological Parameters | Stillbirth Rate Estimates 2000 (SNL/immpact) | Stillbirth Rate Estimates 2000 (WHO) | Stillbirth Rate Estimates 2005 | Intrapartum Stillbirth Rate 2000 | Stillbirth Cause-of-death 2005 |
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Defi nition | For international comparison stillbirth rates refer only to late fetal deaths (>1000g or >28 weeks gest). ICD-10 defines a fetal death as «death prior to the complete expulsion or extraction from its mother of a product of conception, irrespective of the duration of pregnancy; the death is indicated by the fact that after such separation the fetus does not breathe or show any other evidence of life, such as beating of the heart, pulsation of the umbilical cord, or definite movement of voluntary muscles» without specification of the duration of pregnancy. The denominator is all live births plus late fetal deaths. | Stillbirths in the last trimester (late fetal deaths) occurring during the time of labour, but excluding major congenital abnormalities. In verbal autopsy data «fresh stillbirth» is used as a surrogate marker for intrapartum stillbirth. The denominator is all live births plus late fetal deaths. | Multiple classification systems are in use. A comparable system to map the results of verbal autopsy data on cause-of-death with more complex classification systems is urgently needed. | ||
Systematic global estimates available? Source and date | Stanton, Lawn et al, Lancet 2006 | WHO MPS, 2006 | GAPPS, GBD, CHERG, WHO (Stanton, Lawn et al in process) | Lawn, Shibuya, Stein WHO Bull, 2005 | GAPPS, GBD, CHERG, WHO (Stanton, Lawn et al in process) |
   N of countries with VR data used (note if used as reported, new analysis or adjusted) | 44 countries with adult VR coverage > 90%; rates adjusted by model coefficient for VR to allow for under reporting | 102 countries with SBR data used as reported; | 33 VR (plus 11 from EuroPeristat, some of which are VR-based) | Not in Vital registration | Not in vital registration |
   N of countries with survey-based estimate used (note if used as is, new analysis or adjusted) | 1 country, adjusted by model coefficient | 102 countries with SBR data used as reported; | In process - | Not in current national surveys | Only 1 national surveys with SB COD data |
   N of countries where model-based estimate is used (basis of model) | Model-based estimates are used for 128 countries; based on a random eff ects model | 88 countries - based on average SBR:ENMR ratio for that region | (in process) | 52 countries with data, 141 countries with estimate based unadjusted reported data by country or if no country data on median for WHO subregion (14 subregions) | (in process) |
   Types of data inputs used in the model | VR, published studies from community and facility-based studies, household surveys, unpublished datasets | Historical data from 12 High Income Countries were used to calculate a ratio of SBR:ENMR, and was applied to generate SBR from ENNMR for high mortality settings | VR, published data from community and facility-based studies, household surveys, unpublished datasets | National registries, published data from community and facility-based studies, unpublished datasets | National registries, published studies from community and facilities, unpublished datasets |
   N of observations included in estimation dataset | 323 observations resulting from searches of 33,714 citations, plus household surveys and additional unpublished datasets | 102 country estimates, plus historical trend data from 12 developed countries | 437 observations | 73 observations resulting from searches of 13,496 citations | ~70 datasets |
   Median year of input data | Median year for High Income Countries = 1998; Median year for Low Income Countries = 1990 | Acceptable date range not specifi ed | 2000 | 1995 | 2000 (range 1981-2008) |
   Variability in outcome measurement methods | Yes | Yes | Yes | Yes | Yes, includes clinical assessment; medical records, ICD codes, Verbal Autopsy results |
   Limitations re: population representativeness | Yes; ~20% of observations from sub-Saharan Africa and South Asia rely on data from hospital studies (likely biased) | No, all observations used were national in scope | Yes; ~41% of observations from both sub-Saharan Africa and S/ SE Asia rely on data from hospital studies (likely biased) | Study based data often from non representative populations | Yes, ~68% of low income country obs from hospital data |
   Generalizability to population of interest (ie., match between burden of disease and geographic distribution of data ) | 73% of observations in dataset from Low Income Countries; 24% from sub-Saharan Africa; 21% from SE and S Asia | 47 Low Income Countries had estimates based on the 1.2 SBR:ENMR ratio from historical High Income Countries | 56% of observations from high income countries | Important gaps in the input data, especially: China, central Africa and central Asia | ~40% of observations from low income countries |
   Is there systematic equity assessment | No | No | No | No | No |
   Global estimate | SBRate = 24 per 1000 births N of stillbirths = 3.2 million | SBRate =24 per 1000 births N of stillbirths = 3.3 million | (in process) | 1.02 million | (in process) |
   Range | Range of SBRates: 19 – 30 per 1000 Range of N’s of stillbirths: 2.5 - 4.1 million | Wide uncertainty assumed, but not quantified | (in process) | 0.66 million - 1.48 million | (in process) |
   Consistency between estimates if more than one series | Good consistency at global, reasonable at regional but poor at country level | to compare when done | none to compare with | none to compare with | |
Overall summary of quality of data input | Moderate for High Income Countries, low for Low Income Countries | Moderate/low for High Income Countries, very low for Low Income Countries | Â | Moderate/low for High Income Countries, very low for Low Income Countries | Â |
Overall summary of estimates Quality according to standards for global estimates | Moderate - transparent methods but limited by input data and by adjustments made to 18 countries which increases global total of stillbirths by approximately 1 million | Moderate to Poor - limited by input data, not fully transparent inputs, the output for high mortality settings is dependent on ENMR (some of which are model-based) and multiplying all the ENMRs by 1.2, which increases the global total of stillbirths by approximately 1 million ; | Â | Moderate - limited by input data and median-based method which may be less sensitive than results from a regression-based model | Â |
Priority areas to improve measurement now | 1. Increase consistency in use of definitions (weight/gest age cut-off s) 2. Increase quantity and quality of SBR data in vital registration and national audit data 3. Increase quantity and quality of SBR data from household surveys 4. Increase dissemination of country level best estimates of SBRs | 1. Agree on a simple, consistent classifi cation system 2. Increase quantity and quality of stillbirth time and cause-of-death data in vital registration and national audit data 3. Increase quantity and quality of SBR data from verbal autopsies 4. Increase dissemination of country level best estimates of SB time and cause-of-death |