Percent days abstinent at follow-up. Percent days abstinent at pre-treatment and follow-up for patients who received 0, 1 or 12 treatment sessions. The 0 treatment dropout group showed great improvement from pre-treatment to follow-up. The 1 session attendance dropout group had worse scores than did the 0 treatment group. These data suggest that most of the improvement in the full 12 session attendance group cannot be due to treatment. See also Figure 2.
Cutler and Fishbain BMC Public Health 2005 5:75 doi:10.1186/1471-2458-5-75