Neonatal Disorders
Todo
Add a brief introductory paragraph for this document.
Disease Overview
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Add a general clinical overview of the cause.
GBD 2017 Modeling Strategy
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Add an overview of the GBD modeling section, citing [GBD-2017-YLD-Appendix-Neonatal-Disorders] and [GBD-2017-CoD-Appendix-Neonatal-Disorders].
Cause Hierarchy
Restrictions
The following table describes any restrictions in GBD 2017 on the effects of this cause (such as being only fatal or only nonfatal), as well as restrictions on the ages and sexes to which the cause applies.
Restriction Type |
Value |
Notes |
|---|---|---|
Male only |
False |
|
Female only |
False |
|
YLL only |
False |
Note: GBD estimates both YLLs and YLDs for neonatal disorders, but we are ignoring YLDs for this model. See Vivarium Modeling Strategy below. |
YLD only |
False |
|
YLL age group start |
Early Neonatal |
[0, 7 days), age_group_id=2 |
YLL age group end |
Post Neonatal |
[28 days, 1 year), age_group_id=4 |
YLD age group start |
Early Neonatal |
[0, 7 days), age_group_id=2 |
YLD age group end |
95 plus |
[95, 125 years), age_group_id=235 |
Vivarium Modeling Strategy
This model is designed to estimate YLLs due to neonatal disorders that could be averted by an intervention that affects Low Birth Weight and Short Gestation (LBWSG). The model groups together all of the neonatal sub-causes, and is fatal-only (no disability). The rationale for this design is as follows:
All of the neonatal sub-causes (except sepsis – see Assumptions and Limitations below) have the same 2-state cause model structure: “with condition” and “free of condition”, with no between-state transitions.
All of the causes affected by the LBWSG risk factor have the same relative risks and hence will be affected in the same way by shifts between LBWSG categories. Thus, for the purposes of measuring the effects of an intervention on LBWSG, we can group together all the neonatal sub-causes into a single model of the parent cause, neonatal disorders.
Based on the available data (in particular, the missing prevalence of other neonatal disorders and lack of data about comorbidity between the neonatal sub-causes), it is unclear how to compute an appropriate average disability weight for the collection of all neonatal disorders. For the age groups we’re considering in the BEP model (0-2 years), the ratio of YLDs to YLLs for neonatal disorders is very small, so we choose not to model disability for this cause.
Todo
Look into data and provide an estimate of neonatal YLDs as a fraction of neonatal DALYs for relevant age groups.
Scope
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Describe which aspects of the disease this cause model is designed to simulate, and which aspects it is not designed to simulate.
Assumptions and Limitations
We assume no transitions between the “with condition” and “free of condition” states because this is the behavior of all of the neonatal sub-causes except Neonatal Sepsis, which has SIS dynamics. We expect this no-transisions assumption to be sufficiently accurate because we compared a model of Neonatal Sepsis with no remission or post-birth incidence against GBD 2017, and the results were very close [cite Kiran’s code once it’s on GitHub].
Cause Model Diagram
State and Transition Data Tables
State |
State Name |
Definition |
|---|---|---|
C |
With Condition |
Infant developed neonatal disorders |
F |
Free of Condition |
Infant did not develop neonatal disorders |
State |
Measure |
Value |
Notes |
|---|---|---|---|
C |
prevalence |
prevalence_c380 |
|
C |
birth prevalence |
birth_prevalence_c380 |
|
C |
excess mortality rate |
\(\frac{\text{deaths\_c380}}{\text{population} \,\times\, \text{prevalence\_c380}}\) |
= (cause-specific mortality rate) / prevalence |
C |
disability weight |
N/A |
this is a fatal-only model |
F |
prevalence |
1 – prevalence_c380 |
|
F |
birth prevalence |
1 – birth_prevalence_c380 |
|
F |
excess mortality rate |
0 |
|
F |
disability weight |
N/A |
this is a fatal-only model |
All |
cause-specific mortality rate |
\(\frac{\text{deaths\_c380}}{\text{population}}\) |
Transition |
Source State |
Sink State |
Value |
Notes |
|---|---|---|---|---|
N/A |
N/A |
N/A |
N/A |
N/A |
Value |
Source |
Description |
Notes |
|---|---|---|---|
prevalence_c380 |
como |
Prevalence of neonatal disorders |
|
birth_prevalence_c380 |
como |
Birth prevalence of neonatal disorders |
age_group_id = 164 (at birth) and measure = 6 (incidence) |
deaths_c380 |
codcorrect |
Deaths from neonatal disorders |
|
population |
demography |
Mid-year population for given age/sex/year/location |
Validation Criteria
References
Pages 276-295 in Supplementary appendix 1 to the GBD 2017 YLD Capstone:
(GBD 2017 YLD Capstone) GBD 2017 Disease and Injury Incidence and Prevalence Collaborators. Global, regional, and national incidence, prevalence, and years lived with disability for 354 diseases and injuries for 195 countries and territories, 1990–2017: a systematic analysis for the Global Burden of Disease Study 2017. Lancet 2018; 392: 1789–858. DOI: https://doi.org/10.1016/S0140-6736(18)32279-7
Pages 175-176 in Supplementary appendix 1 to the GBD 2017 CoD Capstone:
(GBD 2017 CoD Capstone) GBD 2017 Causes of Death Collaborators. Global, regional, and national age-sex-specific mortality for 282 causes of death in 195 countries and territories, 1980–2017: a systematic analysis for the Global Burden of Disease Study 2017. Lancet 2018; 392: 1736–88. DOI: http://dx.doi.org/10.1016/S0140-6736(18)32203-7