Table 2. Number of follow-up test takers in 1 year according to age group (n=264).

Age at first test (mo)	Age at follow-up test (mo)	No. (%)
4–6	8–9	23 (8.7)
	10–11	96 (36.4)
	12–13	78 (29.5)
8–9	18–19	5 (1.9)
10–11	18–19	16 (6.1)
	20–21	6 (2.3)
	22–23	1 (0.4)
12–13	18–19	7 (2.7)
	20–21	4 (1.5)
	22–23	3 (1.1)
18–19	30–32	1 (0.4)
20–21	30–32	2 (0.8)
22–23	30–32	3 (1.1)
24–26	30–32	2 (0.8)
	33–35	1 (0.4)
30–32	42–47	1 (0.4)
33–35	42–47	3 (1.1)
36–41	42–47	6 (2.3)
42–47	54–59	5 (1.9)
60–65	66–71	1 (0.4)
Total		264

Values are presented as number of cases (%).