Telepsychiatry treatment outcome research methodology: efficacy versus effectiveness.

The use of videoconferencing technology to provide mental health services (telepsychiatry) offers hope for addressing longstanding problems regarding work force shortages and access to care, especially in remote or rural areas. However, data on treatment outcomes (i.e., based on randomized clinical trials) from telepsychiatry applications are virtually nonexistent, representing an important gap in the literature. An important methodological decision point in developing treatment outcome research is whether to take an efficacy or effectiveness approach. Efficacy approaches offer enhanced internal validity; however, they may have limited generalizability to real-world settings. Effectiveness approaches offer enhanced external validity. But, they are typically less controlled than efficacy studies, thereby limiting the assumptions that can be made about causality. The current state of telepsychiatry research necessitates efficacy studies, the outcomes from which can be used to inform future effectiveness studies.