Table 4.

Details of conversion status depending on the age groups screened and detected by ACD from February 2015 to January 2017

Year groups	Group	1st→2nd (%)	2nd→3rd (%)	3rd→4th (%)	4th→5th (%)	5th→6th (%)
<5 years	Negative conversion rate (Positive→Negative)	65.8	51.9	36.4	73.7	69.6
	Positive conversion rate (Negative→Positive)	15.9	23.9	41.2	13.5	19.3
	Sample No./Total sample No.	400/689	278/400	342/501	375/539	359/474
5–10 years	Negative conversion rate	59.6	51.8	37.6	74.9	71.7
	Positive conversion rate	16.1	24.5	40.0	15.5	19.6
	Sample No./Total sample No.	737/1,239	497/916	608/987	659/968	619/827
>10 years	Negative conversion rate	0.0	76.5	65.2	82.8	78.7
	Positive conversion rate	6.8	12.4	16.0	7.2	6.5
	Sample No./Total sample No.	766/1,510	486/767	563/1,024	539/961	537/846
Total	Negative conversion rate	66.8	57.8	47.2	76.6	74.3
	Positive conversion rate	11.0	17.6	27.9	10.9	13.0
	Sample No./Total sample No.	1,535/2,815	1,005/1,537	1,209/1,998	1,256/2,147	1,210/1,743