Table 3.

Post hoc mixed model analysis of the effect of risk type on percent days abstinent (PDA; arcsine transformed) at 3, 6, and 12-month follow-up.

	df	F	β
Time with High-Risk Friends
3-Month Assessment
PDA at 3-Month Follow-up	1, 240	58.39**	−0.37
PDA at 6-Month Follow-up	1, 202	28.83**	−0.40
PDA at 12-Month Follow-up	1, 189	30.15**	−0.48
6-Month Assessment
PDA at 6-Month Follow-up	1, 213	18.31**	−0.30
PDA at 12-Month Follow-up	1, 186	18.88**	−0.36
12-Month Assessment
PDA at 12-Month Follow-up	1, 198	38.90**	−0.46
Time with Low-Risk Friends
3-Month Assessment
PDA at 3-Month Follow-up	1, 240	5.53*	0.11
PDA at 6-Month Follow-up	1, 202	7.25**	0.19
PDA at 12-Month Follow-up	1, 189	5.07*	0.19
6-Month Assessment
PDA at 6-Month Follow-up	1, 213	37.43**	0.39
PDA at 12-Month Follow-up	1, 186	23.29**	0.37
12-Month Assessment
PDA at 12-Month Follow-up	1, 198	13.34**	0.29
Net-Risk of Time with Friends
3-Month Assessment
PDA at 3-Month Follow-up	1, 240	35.62**	−0.004
PDA at 6-Month Follow-up	1, 202	19.14**	−0.005
PDA at 12-Month Follow-up	1, 189	19.29**	−0.006
6-Month Assessment
PDA at 6-Month Follow-up	1, 213	36.18**	−0.006
PDA at 12-Month Follow-up	1, 186	41.73**	−0.007
12-Month Assessment
PDA at 12-Month Follow-up	1, 198	50.15**	−0.008

Notes: β represents unstandardized parameter estimates of arcsine transformed PDA data;

^*p < 0.05,

^**p < 0.01.