Designing payment for Collaborative Care for Depression in primary care

Collaborative Care for Depression (CCD) in primary care redesigns care processes to incorporate evidence-based depression treatment guidelines and components of the Chronic Care Model (Wagner 2000; Wagner, Austin, and Von Korff 1996). A central element of the model is a care manager in the clinic who serves as a physician extender and conducts patient assessment, education, follow-ups, and care coordination, largely outside a patient’s visits to his/her primary care physician (PCP) (Schulberg et al. 2001). More than 30 randomized controlled trials have shown that CCD improves depression outcomes, patient adherence to treatment, and satisfaction with care (Gilbody et al. 2006; Neumeyer-Gromen et al. 2004; Williams et al. 2007). The prevailing visit-based fee-for-service physician payment system, however, constitutes a serious disincentive for providing this service (Bachman et al. 2006; Berenson, and Horvath 2003; Unutzer et al. 2006; Wolff, and Boult 2005). Recognizing the importance of a payment mechanism, several recent large-scale implementation initiatives adopted case-rate based payment models to cover the cost of delivering evidence-based CCD. The Depression Improvement Across Minnesota, Offering a New Direction (DIAMOND) initiative adopted a flat monthly case rate (Institute for Clinical Systems Improvement 2008). This monthly rate was determined based on the average monthly cost of a 12-month CCD intervention tested in a randomized controlled trial (RCT) known as IMPACT (Improving Mood-Promoting Access to Collaborative Treatment) (Unutzer et al. 2002b). A more recent implementation of the IMPACT model to treat a broader set of behavioral health disorders among community health centers in Washington state adopted a lump sum payment to each clinic covering the cost of the yearlong program, with minimum caseload expectations and 25% of the payment retained to reward providers achieving pre-specified depression treatment and outcome targets. The CCD payment in both initiatives is intended to cover CCD program cost to the clinic that is not covered by the visit-based physician payment. The underlying goals of these pioneering efforts to pay for CCD are twofold: 1) to adequately cover the cost of providing CCD, and 2) to align incentives with the delivery of CCD in a way that leads to better outcomes. The design of such a payment should reflect meaningful variation in resource requirement for evidence-based practice of CCD. In addition, it requires a consideration of incentives associated with a given design, and ways to address or ameliorate related issues. In this paper, we used data from a large randomized controlled trial, the IMPACT study (Unutzer et al. 2002b; Unutzer et al. 2001) to investigate salient and feasible properties of a bundled case rate payment design for CCD. In IMPACT, with close monitoring and guidance from the research team, the CCD intervention protocol was implemented with high fidelity. Meanwhile, participating practices came from diverse community and organizational settings (Unutzer et al. 2001). Delivery of CCD as seen in IMPACT thus represents probably the closest to evidence-based practice in “real-world” implementation where provider adoption of financial strategies is likely to be minimal. This unique feature of the data enables us to identify factors accounting for practically significant variation in resource use of CCD, which then guided our recommendation of two case rate based payment models. We further compared implications for health care organizations in the IMPACT study of alternative payment models..