Follow-up rates were also low (5.6% of the randomized sample were reached for 6-month follow-up assessment); making it difficult to make inferences regarding the efficacy of the program. The studies reviewed above highlight both the promise of technology-based interventions as well as their significant limitations, which include highly variable rates of retention and adherence and poor rates of follow-up, particularly for studies collected entirely on-line (Kiluk et al., 2010). Several studies have used use wait-list controls, hence limiting the inferences that can be drawn regarding the efficacy of the intervention evaluated. Issues of privacy and confidentiality are particularly important to consider when dealing with individuals who are users of illicit drugs, particularly in the era of electronic medical records (Ramsey et al., 2016). Finally, while validated technology based interventions are generally less expensive than traditional clinician-delivered interventions, the lack of a reimbursement structure for these interventions constrains their availability to date.
