Ridgeway 1999.

Study characteristics
Methods	Improved control of type 2 diabetes mellitus: a practical education/behavior modification program in a primary care clinic RCT (NA clusters and NA providers), conducted in 1) The study was conducted at the University Physicians Practice Group ambulatory clinic in Kingsport, Tenn (primary care clinic). This is a private faculty clinic staffed by 5 board certified general internists who are full‐time faculty members of the East Tennessee State University James H. Quillen College of Medicine. These physicians provide longitudinal care for typical general internal medicine patients, 45% of whom are insured by Medicare carriers. 2) The education classes were held by a registered nurse with a Bachelor of Science degree and a registered dietitian, both of whom were certified diabetes educators. In United States of America. 2 arms: 1. Control (usual office visits) (control arm) and 2. Intervention (office‐based education/training classes) (intervention arm)
Participants	Control arm N: 28 Intervention arm N: 28, NA, NA Diabetes type: 2 Mean age: 63.58 ± NR % Male: 28.95 Longest follow‐up: 12 months
Interventions	Control arm: (usual office visits) Intervention arm: (office‐based education/training classes) 1) Case management 2) Team change 3) Patient education 4) Promotion of self‐management 5) Patient reminders
Outcomes	Glycated haemoglobin Low‐density lipoprotein
Funding source	Supported by a grant from the Department of Medicine, James H. Quillen College of Medicine, East Tennessee State University, Johnson City
Notes	—
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not reported. Patients were divided randomly into 2 groups.
Allocation concealment (selection bias)	Unclear risk	Not reported.
Patient's baseline characteristics (selection bias)	Unclear risk	Table 1. No P values. Data reported only for completers.
Patient's baseline outcomes (selection bias)	Unclear risk	Table 1. No P values. Triglyceride looks higher in intervention group (634 vs 381 in control group). Data reported only for completers.
Incomplete outcome data (attrition bias)	High risk	They lost 18 patients out of 56 randomised (32%). Ten patients dropped out of the intervention group because of intercurrent illness or failure to attend classes or to have adequate laboratory studies (36%). Eight patients were dropped from the control group because of failure to return for their usual appointments or because of significant intercurrent illnesses (29%). Calculation of LDL‐C was limited to 12 patients.
Blinding of participants and personnel (performance bias) and of outcome assessors (detection bias)	Low risk	Our outcomes of interest were objectively measured (HbA1c and LDL).
Selective reporting (reporting bias)	High risk	No registered or published protocol. At the monthly sessions, patients were informed of their weight, blood pressure and laboratory results. No data reported for blood pressure.
Risk of contamination (other bias)	Unclear risk	Only the intervention group had office visits. However, physicians were following patients in both the control and intervention group. Physicians were not "blinded" to the intervention. Physicians may have changed behaviour based on interactions with intervention group.
Other bias	Low risk	No evidence of other risk of bias.