Judging outcomes in psychosocial interventions for dementia caregivers: the problem of treatment implementation

In published dementia caregiver intervention research, there is widespread failure to measure the level at which treatment was implemented as intended, thereby introducing threats to internal and external validity. The purpose of this article is to discuss the importance of inducing and assessing treatment implementation (TI) strategies in caregiving trials and to propose Lichstein's TI model as a potential guide. The efforts of a large cooperative research study of caregiving interventions, Resources for Enhancing Alzheimer's Caregiver Health (REACH), illustrates induction and assessment of the three components of TI: delivery, receipt, and enactment. The approaches taken in REACH vary with the intervention protocols and include using treatment manuals, training and certification of interventionists, and continuous monitoring of actual implementation. Investigation and description of treatment process variables allows researchers to understand which aspects of the intervention are responsible for therapeutic change, potentially resulting in development of more efficacious and efficient interventions.