ABSTRACT
281Several major limitations should be noted in interpreting and comparing the results of the two follow-up studies presented. First, the NTA sample was drawn randomly from the universe of NTA clients, stratified by modality and the year in which the client left treatment. Thus, the sample is representative of all clients within each cell irrespective of the NTA clinic at which the client was treated and (except for the comparison group) the length of time spent in treatment. Few clients of drug free programs are included because NTA had few such clients; such persons are commonly treated by programs outside of NTA. In contrast, the ASA sample is stratified, not only by modality, but also by the length of time clients spent in ASA treatment. Thus, 27 percent of the former ASA clients interviewed were graduates or still in treatment; an additional 26 percent were in continuous treatment for over 12 months. The NTA sample contained few graduates or persons in treatment and few persons in continuous treatment for more than one year. One would expect that clients in a program would be less “at risk” than those not in a program and one would hope that graduates would be less likely to have undesirable outcomes than persons who have not graduated.
