New Delhi: India on Saturday, April 16, questioned the World Health Organization’s methodology to estimate Covid-19 mortalities in the country.
India said that such mathematical modelling cannot be applied to estimate the death figures for such a vast nation of geographical size and population, according to media reports.
In response to a New York Times article titled ‘India Is Stalling WHO's Efforts to Make Global Covid Death Toll Public’, and dated April 16, the Union Ministry of Health and Family Welfare issued a statement saying that India on several occasions shared its concerns with the global health body over the methodology used.
India has been in regular and in-depth technical exchange with the WHO on the issue, with the analysis using a mathematical modelling approach for Tier II countries that include India, the ministry said.
"India's basic objection has not been with the result (whatever they might have been), but rather the methodology adopted for the same.
"The model gives two highly different sets of excess mortality estimates of when using the data from Tier I countries and when using unverified data from 18 Indian states. Such a wide variation in estimates raises concerns about validity and accuracy of such a modelling exercise," the Union health ministry said in the statement.
According to the Union health ministry, India has shared its concerns with the methodology along with other member states through a series of formal communications, including six letters issued to WHO (on November 17, December 20, 2021; December 28, 2021; January 11, 2022; February 12, 2022; and March 2, 2022) and virtual meetings held on December 16, 2021, December 28, 2021, January 6, 2022, February 25, 2022 and the SEARO Regional Webinar held on February 10, 2022.
Specific queries have been raised by India along with other member states including China, Iran, Bangladesh, Syria, Ethiopia and Egypt during these exchanges.
The statement said that the concern specifically includes on how the statistical model projects estimates for a country of geographical size and population of India and also fits in with other countries which have smaller populations.
"WHO is yet to share the confidence interval for the present statistical model across various countries," the statement said.
"India has asserted that if the model is accurate and reliable, it should be authenticated by running it for all Tier I countries and if the result of such exercise may be shared with all member states," it added. The model assumes an inverse relationship between monthly temperature and monthly average deaths.
All states in India have widely varied seasonal patterns. "Thus, estimating national level mortality based on these 18 states data is statistically unproven," the statement said.
The modelling for Tier II countries is based on the Global Health Estimates (GHE) 2019. The GHE itself is an estimate.
The statement said that the present modelling exercise seems to be providing its own set of estimates based on another set of historic estimates, while disregarding the data available with the country.
"It is not clear as to why GHE 2019 has been used for estimating expected death figures for India, whereas for the Tier 1 countries, their own historical datasets were used when it has been repeatedly highlighted that India has a robust system of data collection and management," the statement said.
The WHO determined standard patterns for age and sex for the countries with reported data (61 countries) and then generalised them to the other countries, including India, who had no such distribution in their mortality data, in order to calculate the age-sex death distribution for India.
According to the statement, India's age-sex distribution of predicted deaths was extrapolated based on the age-sex distribution of deaths reported by four countries (Costa Rica, Israel, Paraguay and Tunisia).
"The test positivity rate for Covid in India was never uniform throughout the country at any point of time. But, this variation in Covid positivity rate within India was not considered for modelling purposes,” the statement said.
"Further, India has undertaken COVID-19 testing at a much faster rate than what WHO has advised. India has maintained molecular testing as preferred testing methods and used Rapid Antigen as screening purpose only. Whether these factors have been used in the model for India is still unanswered," the statement added.
(With PTI Inputs)