Table 1.

Summary of experimental designs to test effectiveness of behavioral and pharmacological interventions in community-based treatment settings.

Design 1: New intervention versus Treatment as Usual (TAU)
Primary question addressed:
--How does the effectiveness of a new treatment intervention compare to existing community-based treatment (TAU)?
Suitable interventions to test:
--Treatment approaches that are comprehensive, stand-alone interventions that would substitute entirely for TAU.
Design 2a: New intervention + TAU versus TAU; New intervention is an add-on to TAU
Primary question addressed:
--What is the impact of adding a new treatment intervention to an existing treatment program or TAU?
Suitable interventions to test:
--The intervention is inherently an add-on to an existing treatment program (TAU), not a replacement for part of TAU.
Design 2b: New Intervention + TAU vs TAU; New intervention substitutes for a part of TAU
Primary question addressed:
--What is the impact of substituting a new treatment intervention for an existing component of TAU?
Suitable interventions to test:
--The intervention is inherently a substitute for a component or service currently provided as part of TAU.
Design 3: New Intervention + TAU versus Control Intervention + TAU
Primary question addressed:
--What is the impact of adding a new treatment intervention to existing TAU, over and above the impact of adding a Control intervention? The Control intervention may be designed to control fully for attention, isolating the effect of the specific elements of the new intervention; or, the Control intervention may be designed to standardize some aspect of current TAU.
Suitable treatments to test:
--The treatment should be inherently suitable as an add-on to TAU, or substitute for a component of TAU.
Design 4: New Intervention vs Control Intervention
Primary question addressed:
--What is the impact on outcome of a new treatment intervention compared to a control intervention.
Suitable treatments to test:
--As for Design 1, the treatment is a comprehensive, stand-alone interventions that would substitute entirely for TAU.