Table 3. Harms and benefits of cervical screening starting from age 20 compared with starting from age 25.

Age group (years)	100 000 women invited from age 20 years	100 000 women invited from age 25 years	Excess in women invited from age 20 years
Screening tests
20–24	134 961	0
25–26	54 857	70 710
Sum	189 818	70 710	119 108
Non-negative test resultsa
20–24	23 968	0
25–26	6988	10 558
Sum	30 956	10 558	20 398
Referred to colposcopy
20–24	10 082	0
25–26	3346	5252
Sum	13 427	5252	8175
Treated (excision, ablation)
20–24	3885	0
25–26	1606	2657
Sum	5491	2657	2834

^aThe number of non-negative screening episodes is obtained by multiplying the number of screens by the proportion of women with a non-negative (borderline changes or worse) test.