BACKGROUND:We compared two implementation approaches for a health literacy diabetes intervention designed for community health centers. METHODS: A quasi-experimental, clinic-randomized evaluation was conducted at six community health centers from rural, suburban, and urban locations in Missouri between August 2008 and January 2010. In all, 486 adult patients with type 2 diabetes mellitus participated. Clinics were set up to implement either: 1) a clinic-based approach that involved practice re-design to routinely provide brief diabetes education and counseling services, set action-plans, and perform follow-up without additional financial resources [CARVE-IN]; or 2) an outsourced approach where clinics referred patients to a telephone-based diabetes educator for the same services [CARVE-OUT]. The fidelity of each intervention was determined by the number of contacts with patients, self-report of services received, and patient satisfaction. Intervention effectiveness was investigated by assessing patient knowledge, self-efficacy, health behaviors, and clinical outcomes. RESULTS: Carve-out patients received on average 4.3 contacts (SD=2.2) from the telephone-based diabetes educator versus 1.7 contacts (SD=2.0) from the clinic nurse in the carve-in arm (p<0.001). They were also more likely to recall setting action plans and rated the process more positively than carve-in patients (p<0.001). Few differences in diabetes knowledge, self-efficacy, or health behaviors were found between the two approaches. However, clinical outcomes did vary in multivariable analyses; carve-out patients had a lower HbA1c (β= −0.31, 95 % CI −0.56 to −0.06, p=0.02), systolic blood pressure (β=−3.65, 95 % CI −6.39 to −0.90, p=0.01), and low-density lipoprotein (LDL) cholesterol (β=−7.96, 95 % CI −10.08 to −5.83, p<0.001) at 6 months. CONCLUSION: An outsourced diabetes education and counseling approach for community health centers