Challenges in estimating the burden of neurological disorders across Indian states – Authors' reply
Authors: Lalit Dandona, Gagandeep Singh
Journal: The Lancet Global Health (2021)

As we have noted previously, there are limitations in the cause of death data sources available in India.1Dandona L Dandona R Kumar GA et al.Nations within a nation: variations in epidemiological transition across the states of India, 1990–2016 in the Global Burden of Disease Study.Lancet. 2017; 390: 2437-2460Summary Full Text Full Text PDF PubMed Scopus (370) Google Scholar The Medical Certification of Cause of Death (MCCD) data reporting system in the Civil Registration System (CRS) covered less than 20% of the total estimated deaths in India in 2019.2Office of the Registrar General of IndiaReport on Medical Certification of Cause of Death 2019. June, 2021.https://censusindia.gov.in/2011-Documents/mccd_Report1/MCCD_Report_2019.pdfDate accessed: August 30, 2021Google Scholar, 3Office of the Registrar General and Census Commissioner of IndiaSample Registration System statistical report 2018. June, 2020.https://censusindia.gov.in/Vital_Statistics/SRS_Report_2018/SRS_Statistical_Report_2018.pdfDate accessed: August 30, 2021Google Scholar In the absence of an adequate MCCD system in India, the nationwide verbal autopsy data from the Sample Registration System (SRS), which includes 4961 rural and 3886 urban clusters covering about 8 million people, provides a representative sample.3Office of the Registrar General and Census Commissioner of IndiaSample Registration System statistical report 2018. June, 2020.https://censusindia.gov.in/Vital_Statistics/SRS_Report_2018/SRS_Statistical_Report_2018.pdfDate accessed: August 30, 2021Google Scholar Although not ideal, the SRS verbal autopsy is considered a reasonable alternative for ascertaining cause of death distribution at the population level.1Dandona L Dandona R Kumar GA et al.Nations within a nation: variations in epidemiological transition across the states of India, 1990–2016 in the Global Burden of Disease Study.Lancet. 2017; 390: 2437-2460Summary Full Text Full Text PDF PubMed Scopus (370) Google Scholar Regarding the CRS mortality data mentioned by Rajinder Dhamija and Alvee Saluja, although these data might be an increasingly useful source for mortality rates in some age groups, the substantial proportion of registered deaths for which age data are not available is a considerable limitation.4Kumar GA Dandona L Dandona R Completeness of death registration in the Civil Registration System, India (2005 to 2015).Indian J Med Res. 2019; 149: 740-747Crossref PubMed Scopus (9) Google Scholar Furthermore, the cause of death data in the death report form number 2 of the CRS are self-reported,5Office of the Registrar General and Census Commissioner of IndiaDeath report form no 2.https://crsorgi.gov.in/web/uploads/download/all_forms_CRS_2019_new.pdfDate: 2019Date accessed: August 30, 2021Google Scholar and therefore not considered reliable. For India, the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) uses cause of death data from SRS for many causes, from MCCD for select causes, and from subnational population-based verbal autopsy studies and population registries, as suitable. These data sources were used to estimate deaths from neurological disorders in our paper. For some less common neurological disorders for which data are not readily available, the best possible estimates were generated with use of covariates that have an established association with deaths from particular disorders, and with use of customised modelling approaches. GBD uses a range of techniques to maximise the quality, standardisation, and comparability of the cause of death data from various sources, as described elsewhere.6Vos T Lim SS Abbafati C et al.Global burden of 369 diseases and injuries in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019.Lancet. 2020; 396: 1204-1222Summary Full Text Full Text PDF PubMed Scopus (1395) Google Scholar We have reported death estimates of neurological disorders using all accessible data and standardised GBD methods; however, these estimates can be improved if the cause of death data system in India is enhanced. Major focus is needed to substantially strengthen MCCD and provide good quality cause of death data across India. As the MCCD strengthening will take some time, in the interim, the major delays of several years in SRS verbal autopsy cause of death data reporting should be avoided. Avoiding delays can be achieved with the use of available automated algorithms that have reasonable accuracy in assigning cause of death rapidly, instead of continuing to use the tedious, time-consuming, and costly physician coding of verbal autopsies in the SRS. LD works with the Indian Council of Medical Research, which partly funded the research. GS declares no competing interests. Challenges in estimating the burden of neurological disorders across Indian statesWe read with great interest the study by the India State-Level Disease Burden Initiative Neurological Disorders Collaborators, published in The Lancet Global Health.1 The study, as part of the Global Burden of Diseases, Injuries, and Risk Factors Study 2019, aimed to estimate the burden of various neurological disorders across Indian states from 1990 to 2019. Although the study had a sound methodology, we think a number of questions need to be addressed, in particular regarding the mortality estimates. Full-Text PDF Open AccessThe burden of neurological disorders across the states of India: the Global Burden of Disease Study 1990–2019The increasing contribution of non-communicable and injury-related neurological disorders to the overall disease burden in India, and the substantial state-level variation in the burden of many neurological disorders highlight the need for state-specific health system responses to address the gaps in neurology services related to awareness, early identification, treatment, and rehabilitation. Full-Text PDF Open Access