TABLE 1.

Sample Participation at Baseline and at 6, 12, and 18 Months

	Baseline	6 Months	12 Months	18 Months
Group 1	23 (100.0)	23 (100.0)	23 (100.0)	23 (100.0)
Male	13 (56.5)	12 (52.2)	10 (43.5)	7 (30.4)
Female	10 (43.5)	6 (26.1)	6 (26.1)	3 (13.0)
Missing	0 (0.0)	5 (21.7)	7 (30.4)	13 (56.5)
Group 2	24 (100.0)	24 (100.0)	24 (100.0)	24 (100.0)
Male	13 (54.2)	10 (41.7)	6 (25.0)	6 (25.0)
Female	11 (45.8)	9 (37.5)	7 (29.2)	1 (4.2)
Missing	0 (0.0)	5 (20.8)	11 (45.8)	17 (70.8)

All data are expressed as n (%).