The findings of a paper published in academic journal Science Advances on life expectancy during the Covid pandemic in India in 2020 are based on "untenable and unacceptable" estimates, the Union health ministry said on Saturday after the findings were highlighted in some media reports. While the paper's authors claim to have followed standard methodology of analysing the National Family Health Survey-5 (NFHS-5), there are critical flaws in the methodology, the ministry said in a statement.

"The most important flaw is that the authors have taken a subset of households included in the NFHS survey between January and April 2021, compared mortality in these households in 2020 with 2019, and extrapolated the results to the entire country," it said.

The NFHS sample is representative of the country only when it is considered as a whole. The 23 per cent of households included in this analysis from part of 14 states cannot be considered representative of the country, the statement said.

"The other critical flaw is related to possible selection and reporting biases in the included sample due to the time in which these data were collected, at the peak of the COVID-19 pandemic," it said.

It stated that the paper erroneously argues for the need for such analyses claiming that vital registration system in low and middle income countries, including India, is weak.

"This is far from being correct. The Civil Registration System (CRS) in India is highly robust and captures over 99 per cent of deaths. This reporting has constantly increased from 75 per cent in 2015 to over 99 per cent in 2020," the statement said.

Data from this system shows death registration has increased by 4.74 lakh in 2020 compared to 2019, it said.

There was a similar increase of 4.86 lakh and 6.90 lakh in death registration in 2018 and 2019 over the respective previous years, the statement said.

"Notably, all excess deaths in a year in the CRS are not attributable to the pandemic. Excess number is also due to an increasing trend of death registration in CRS (it was 92 per cent in 2019) and a larger population base in the succeeding year," it said.

"It is strongly asserted that an excess mortality of about 11.9 lakh deaths reported in the 'Science Advances' paper in 2020 over the previous year is a gross and misleading overestimate," the statement said.

It is noteworthy that excess mortality during the pandemic means increase in deaths due to all causes, and cannot be equated with deaths that were directly caused by Covid, it said.

The erroneous nature of the estimates published by the researchers is further corroborated by data from India's Sample Registration System (SRS), the statement said.

The SRS covers a population of 84 lakh in 24 lakh households in 8,842 sample units spread across 36 states and UTs, it said.

While the authors take great pains to show that results from the NFHS analyses and SRS analyses for 2018 and 2019 are comparable, they completely fail to report that the SRS data in 2020 shows very little, if any, excess mortality compared to the 2019 data (crude death rate 6.0/1000 in 2020, crude death rate 6.0/1000 in 2019) and no reduction in life expectancy, the statement said.

The paper reports results on age and sex, which are contrary to research and program data on COVID-19 in India. The paper claims that excess mortality was greater in females and in younger age groups (particularly 0-19 year old children), it said. Data on about 5.3 lakh recorded deaths due to Covid, as well as research data from cohorts and registries consistently shows higher mortality due to Covid in males than females (2:1) and in older age groups.

These inconsistent and unexplainable results in the published paper further reduce any confidence in its claims, the statement said.

In conclusion, the all-cause excess mortality in 2020 compared with the previous year in India is markedly less than the 11.9 lakh deaths reported in the Science Advances paper.

"The paper published today is methodologically flawed and shows results that are untenable and unacceptable," the statement added.

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