Table 2.

Results of the correlation analysis between the percentage of positive results among performed real-time PCR tests and case fatality rate,^* based on data from the 2020 COVID-19 outbreak in Italy and Lombardy

	Italy		Lombardy
Time period	Correlation coefficient	Average slope (95% CI)	Correlation coefficient	Average slope (95% CI)
February 24–February 29	−0.78	−0.27 (−0.64; 0.11)	−0.46	−0.04 (−0.18; 0.1)
March 1–March 24	0.98†	0.46 (0.42; 0.51)	0.98†	0.38 (0.34; 0.42)
March 25–April 9	−0.92†	−0.35 (−0.43; −0.26)	−0.87†	−0.5 (−0.64; −0.36)
April 10–April 13 (only data from Lombardy)		–	0.87	0.17 (−0.26; 0.6)

^*Case fatality rate is calculated by dividing the number of deaths in patients who tested positive for COVID-19 by the cumulative number of cases at a specific point in time.

^†P < 0.001.