Excess deaths in Ireland from March to June were "substantially" less than the officially reported Covid-19 figures, analysis from the Health Information and Quality Authority has found.
HIQA says this could be due to the inclusion within official figures of people who were infected with coronavirus but whose cause of death may have been predominantly due to other factors.
Excess deaths refers to the number of deaths over and above what would normally be expected for that time of year.
The analysis assessed the number of deaths that occurred in Ireland from 11 March to 16 June relative to the expected number of deaths, using data from the death notices website RIP.ie.
It found that while there were 1,200 more deaths during that period, this is less than the 1,709 people recorded as having died from coronavirus during those months.
HIQA's Chief Scientist, Dr Conor Teljeur, said: "Based on an analysis of the death notices reported on RIP.ie since 2010, there is clear evidence of excess deaths occurring since the first reported death due to Covid-19 in Ireland.
"There were about 1,100 to 1,200 more deaths than we would expect based on historical patterns; a 13% increase between 11 March to 16 June. However, the number of excess deaths is substantially less than the reported 1,709 Covid-19-related deaths over the same period."
HIQA found that the officially-reported Covid-19 deaths likely overestimates the true burden of excess deaths caused by the virus.
This could be due to the inclusion within official figures of people who were infected with SARS-CoV-2 (coronavirus) at the time of death, whose cause of death may have been predominantly due to other factors.
"Excess deaths peaked by 33% over a six-week period from 25 March 2020 to 5 May 2020", Dr Teljeur said.
"During this period, there was an increase of 1,200 deaths from expected figures, with 1,332 Covid-19-related deaths officially reported."
Dr Teljeur said that in the last four weeks of the analysis, they saw a reversal of that trend, with fewer deaths than expected.
However, he said that changes to healthcare delivery – like suspending elective activity in public acute hospitals – might have a lasting impact on health outcomes that could take years to be seen.