Uncovering the Cost-Effectiveness of Theory-Based Implementation Approaches: A Health Economic Analysis of the Hide...

Evidence that a healthcare intervention is clinically effective and cost-effective, and subsequently funded, does not guarantee adoption into routine clinical practice. Implementation science can improve adoption, although it also involves valuable resources. This study assessed the cost-effectiveness of a theory-based implementation approach compared with an intuition-based one, using genetic testing for Lynch syndrome as a case study.

A pragmatic 2-arm cluster randomized controlled trial (the Hide and Seek Project, HaSP) compared the approaches across 7 large Australian hospitals (N = 3321 patients). Costs associated with the implementation approaches and the strategies were collected during the trial, including initial once-off and ongoing strategy costs. Results were incorporated into a published microsimulation model (Policy1-Lynch). Costs were reported in 2021 Australian Dollars (AUD).

Compared with the intuition-based approach, the theory-based approach was previously shown to significantly improve genetics services referral in patients at high risk of developing Lynch syndrome (P < .0001). The within-trial analysis found that a theory-based approach reduced once-off plus ongoing implementation costs by A$ 0.75 per patient versus an intuition-based approach over 5 years. The modeled analysis estimated that a theory-based approach increased health system costs by A$ 103.74 per colorectal cancer patient but resulted in fewer colorectal cancer deaths and more life-years gained and thus cost A$ 37 679 more per life-years gained than an intuition-based approach.

The theory-based approach resulted in more effective strategies and was cost-effective versus an intuition-based approach. Further research is needed to confirm these results in larger trials, other settings, and conditions.