Intervention (n = 120) Intervention (n = 120) Intervention (n = 120) Control (n = 140) Control (n = 140) Control (n = 140)
2 weeks (n = 118)
4 weeks (n = 120)
8 weeks (n = 119)
2 weeks (n = 137) 4 weeks (n = 137) 8 weeks (n = 140)
Never 0 0 0 47 (34.3) 39 (28.5) 34 (24.1)
Occasionally 1 (0.8) 0 0 25 (18.2) 25 (18.2) 25 (17.7)
Once/week 1 (0.8) 0 2 (1.7) 7 (5.1) 9 (6.6) 10 (13.5)
2-3/week 3 (2.5) 3 (2.5) 5 (4.2) 32 (23.4) 40 (29.2) 44 (31.2)
4-6/week 8 (6.8) 6 (5.0) 9 (7.6) 16 (11.7) 17 (12.4) 11 (7.8)
Daily 105 (89.0) 111 (91.7) 103 (86.6) 10 (7.3) 7 (5.1) 8 (5.7)
Twice/day 75 (63.6) 83 (69.2) 87 (73.1) 2 (1.5) 0 0