Frei 2014.

Study characteristics
Methods	Implementation of the chronic care model in small medical practices improves cardiovascular risk but not glycemic control Cluster‐RCT (30 clusters), conducted in primary care physicians (PCPs) participating in routine primary care of unselected patients, Switzerland Two arms: 1. Control (control arm) and 2. Intervention (intervention arm)
Participants	Control arm N: 164 Intervention arm N: 162 Diabetes type: type 2 Mean age: NR ± NR % Male: NR Longest follow‐up: 12 months
Interventions	Control arm: None Intervention arm: 1) Case management 2) Team changes 3) Electronic patient registry 4) Clinician education 5) Clinician reminders 6) Promotion of self‐management
Outcomes	1) HbA1c, mean % (SD) Control arm: pre 7.6 (1.1), post 7.3 (1.0) Intervention arm: pre 7.8 (1.5), post 7.6 (1.2) 2) SBP, mean mmHg (SD) Control arm: pre 137.8 (16.8), post 137.5 (16.9) Intervention arm: pre 140.3 (18.4), post 136.4 (17.5) 3) DBP, mean mmHg (SD) Control arm: pre 78.7 (10.2), post 79.2 (11.2) Intervention arm: pre 83.1 (10.4), post 79.6 (9.9) 4) LDL, mean mg/dL (SD) Control arm: pre 96.7 (42.5), post 100.5 (38.7) Intervention arm: pre 108.3 (42.5), post 104.4 (38.7)
Funding source	This study was supported by grants from the Swiss Academy of Medical Sciences (grants RRMA 8‐09 and RRMA 13/10) and from the Margrit und Ruth Stellmacher Foundation
Notes	—
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer randomly generated As and Bs and attached #1 to #30 to them; they then put these tickets into an envelope and tickets for intervention and allocation.
Allocation concealment (selection bias)	Low risk	Cluster.
Provider's baseline characteristics (selection bias)	High risk	Control group had more primary care physicians (PCPs) working in single‐handed practices.
Patient's baseline characteristics (selection bias)	Unclear risk	In text, but P values not in table.
Patient's baseline outcomes (selection bias)	Unclear risk	Baseline differences for outcomes was not reported.
Incomplete outcome data (attrition bias)	High risk	Lost to follow‐up ~9% in N1 and ~4% in N2; reasons are imbalanced for "patients nor reliable, almost double in intervention group."
Blinding of participants and personnel (performance bias) and of outcome assessors (detection bias)	Unclear risk	Objective laboratory methods not described.
Selective reporting (reporting bias)	High risk	Secondary outcomes do not match protocol.
Risk of contamination (other bias)	Low risk	Cluster.
Other bias	Low risk	Information not available.