Public health utility of cause of death data: applying empirical algorithms to improve data quality
Authors: Johnson Sarah Charlotte , Cunningham Matthew , Dippenaar Ilse N. , Sharara Fablina , Wool Eve E. , Agesa Kareha M. , Han Chieh , Miller-Petrie Molly K. , Wilson Shadrach , Fuller John E. , Balassyano Shelly , Bertolacci Gregory J. , Davis Weaver Nicole ,   GBD Cause of Death Collaborators, Arabloo Jalal , Badawi Alaa , Bhagavathula Akshaya Srikanth , Burkart Katrin , Cámera Luis Alberto , Carvalho Felix , Castañeda-Orjuela Carlos A. , Choi Jee-Young Jasmine , Chu Dinh-Toi , Dai Xiaochen , Dianatinasab Mostafa , Emmons-Bell Sophia , Fernandes Eduarda , Fischer Florian , Ghashghaee Ahmad , Golechha Mahaveer , Hay Simon I. , Hayat Khezar , Henry Nathaniel J. , Holla Ramesh , Househ Mowafa , Ibitoye Segun Emmanuel , Keramati Maryam , Khan Ejaz Ahmad , Kim Yun Jin , Kisa Adnan , Komaki Hamidreza , Koyanagi Ai , Larson Samantha Leigh , LeGrand Kate E. , Liu Xuefeng , Majeed Azeem , Malekzadeh Reza , Mohajer Bahram , Mohammadian-Hafshejani Abdollah , Mohammadpourhodki Reza , Mohammed Shafiu , Mohebi Farnam , Mokdad Ali H. , Molokhia Mariam , Monasta Lorenzo , Moni Mohammad Ali , Naveed Muhammad , Nguyen Huong Lan Thi , Olagunju Andrew T. , Ostroff Samuel M. , Kan Fatemeh Pashazadeh , Pereira David M. , Pham Hai Quang , Rawaf Salman , Rawaf David Laith , Renzaho Andre M. N. , Ronfani Luca , Samy Abdallah M. , Senthilkumaran Subramanian , Sepanlou Sadaf G. , Shaikh Masood Ali , Shaw David H. , Shibuya Kenji , Singh Jasvinder A. , Skryabin Valentin Yurievich , Skryabina Anna Aleksandrovna , Spurlock Emma Elizabeth , Tadesse Eyayou Girma , Temsah Mohamad-Hani , Tovani-Palone Marcos Roberto , Tran Bach Xuan , Tsegaye Gebiyaw Wudie , Valdez Pascual R. , Vishwanath Prashant M. , Vu Giang Thu , Waheed Yasir , Yonemoto Naohiro , Lozano Rafael , Lopez Alan D. , Murray Christopher J. L. , Naghavi Mohsen 
Published: June 2021

Background

Accurate, comprehensive, cause-specific mortality estimates are crucial for informing public health decision making worldwide. Incorrectly or vaguely assigned deaths, defined as garbage-coded deaths, mask the true cause distribution. The Global Burden of Disease (GBD) study has developed methods to create comparable, timely, cause-specific mortality estimates; an impactful data processing method is the reallocation of garbage-coded deaths to a plausible underlying cause of death. We identify the pattern of garbage-coded deaths in the world and present the methods used to determine their redistribution to generate more plausible cause of death assignments.

Methods

We describe the methods developed for the GBD 2019 study and subsequent iterations to redistribute garbage-coded deaths in vital registration data to plausible underlying causes. These methods include analysis of multiple cause data, negative correlation, impairment, and proportional redistribution. We classify garbage codes into classes according to the level of specificity of the reported cause of death (CoD) and capture trends in the global pattern of proportion of garbage-coded deaths, disaggregated by these classes, and the relationship between this proportion and the Socio-Demographic Index. We examine the relative importance of the top four garbage codes by age and sex and demonstrate the impact of redistribution on the annual GBD CoD rankings.

Results

The proportion of least-specific (class 1 and 2) garbage-coded deaths ranged from 3.7% of all vital registration deaths to 67.3% in 2015, and the age-standardized proportion had an overall negative association with the Socio-Demographic Index. When broken down by age and sex, the category for unspecified lower respiratory infections was responsible for nearly 30% of garbage-coded deaths in those under 1 year of age for both sexes, representing the largest proportion of garbage codes for that age group. We show how the cause distribution by number of deaths changes before and after redistribution for four countries: Brazil, the United States, Japan, and France, highlighting the necessity of accounting for garbage-coded deaths in the GBD.

Conclusions

We provide a detailed description of redistribution methods developed for CoD data in the GBD; these methods represent an overall improvement in empiricism compared to past reliance on a priori knowledge.