Valutazione della qualità delle notifiche di decesso associate a COVID-19 riportate al sistema di sorveglianza integrata COVID-19 ISS: confronto con la rilevazione sulle cause di morte dell’Istat - Italia, 2020

Introduction The rapid spread throughout Italy of SARS-CoV-2 virus infections and associated disease (COVID-19) has resulted in the urgent implementation of a surveillance system coordinated by the Istituto Superiore di Sanità (ISS). The objective of this study is to assess the quality of COVID-19 death notifications reported to the COVID-19 integrated surveillance system of the ISS. Materials and methods Deaths data from the COVID-19 integrated surveillance system of the ISS was compared with those detected by the Istituto Nazionale di Statistica (Istat) Survey on Deaths and Causes of Deaths in the 2020 year. Database of mortality by cause is available from the Statistical Service of the ISS. Analysis was based on information regarding date of death, sex, age (age group, in some cases), Region/Autonomous Province (AP) of death reporting, Region/ AP of residence or domicile. Results The two compared flows show good agreement, with smaller percentage differences in the periods coinciding with the two main epidemic waves (March/April and November/December) and more pronounced in the summer period. In absolute terms, the first wave was characterized by a higher number of deaths reported to ISS COVID-19 integrated surveillance system than those reported among Istat Survey on Deaths and Causes of Deaths (COVID-19 initial cause), while the second wave was characterized by a trend reversal. As regard regional data flows, Piedmont, the AP of Trento, Latium, Basilicata and Sardinia present a lower number of deaths reported to the COVID-19 integrated surveillance than the number of deaths reported to the Istat Survey on Deaths and Causes of Deaths flow (>10% less). Opposite situation regarding Veneto, Friuli Venezia Giulia and Abruzzo where deaths reported to COVID-19 integrated surveillance are >10% more than those classified with initial COVID-19 cause in the Istat causes of death flow. Conclusions Overall, the analysis reported, although at an aggregate level and descriptive only, shows a good correspondence between the two flows. The integrated surveillance system has been found to be an effective tool in capturing such a public health impact-relevant phenomenon as mortality attributable to COVID-19 in Italy