Rönnemaa 1997.

Methods	RCT
Participants	530 people with diabetes mellitus randomised, intervention 267 vs control 263Baseline risk for foot ulceration: no data provided Baseline outcome measures: Foot care knowledge score: intervention 26.7 (SD 11.4) vs control 26.1 (SD 11.8) Self‐care behaviour assessment score: intervention 5.4 (SD 2.8) vs control 5.3 (SD 2.6) Callosities: intervention 18.5% calcaneal region, 54.5% other regions; control 16.8% calcaneal region, 51.3% other regions Diameter of greatest callosity: intervention calcaneal region (n = 49) 40.5 mm (SD 30.8 mm), other regions (n = 141) 16.6 mm (SD 10.2 mm); control calcaneal region (n = 55) 30.6 mm (SD 28.5 mm), other regions (n = 138) 15.2 mm (SD 9.8 mm) Podiatrist visit: intervention 12.4% in previous year, 73.4% never before vs control 10.4% in previous year, 76.1% never before Foot examination by physician in previous year: intervention 36.7% routinely, 9.5% following complaints vs control 46.4% routinely, 12.3% following complaints Study setting: community‐based care in the vicinity of Turku, Finland Inclusion criteria: included in the national drug imbursement register for receiving antidiabetic treatment, no obvious need for podiatry, no visit with podiatrist in previous 6 months, age between 10 to 79 years
Interventions	Intervention group: 45 minutes' individual patient education. Content: education on use of proper footwear, daily hygiene, cutting of toenails, use of emollient cream, avoidance of high‐risk situations and foot gymnastics Podiatric care visits (to 1 of 3 participating podiatrists) of 30 to 60 minutes' duration as necessary. Content: preventive podiatric care as debridement of callus, preparation of insoles, treatment of ingrowing toenails and guidance for foot gymnastics Control group: Written information. Content: instructions on foot care Adherence: intervention mean number of podiatry visits 4.7 in first year. After first and before seventh follow‐up year at least 1 podiatry visit in 82.3% of people in intervention and in 49.7% in control
Outcomes	Primary outcomes: amputation rate, ulcer incidence Secondary outcomes: callus development, foot care knowledge, behaviour assessment scores
Duration and completion of follow‐up	1 and 7 years; 459 completed 1 year of follow‐up: intervention 233 vs control 226 332 completed 7 years of follow‐up: intervention 169 vs control 163
Types of assessment	Callus diameter in millimetres. Knowledge score: 19 three‐choice questions of which 1 or 2 correct answers: correct = 1, unknown = 0, incorrect = 1 (total score range 0 to 57) Behaviour assessment score: range 0 to 12
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Randomisation was performed separately for men and women and for people below and above 20 years of age. Method of randomisation not described
Allocation concealment (selection bias)	Unclear risk	No information provided
Blinding (performance bias and detection bias) Blinding of outcome assessors	Unclear risk	The outcome assessor was blinded to the baseline characteristics, but no further information on blinding to the group allocation is provided
Incomplete outcome data (attrition bias) All outcomes	High risk	Follow‐up was completed by only 63% of people in the intervention group and 62% of people in the control group at 7 years No ITT analysis undertaken
Selective reporting (reporting bias)	Low risk	No study protocol available, but the trial report lists the outcomes of interest in both the methods and the results section
Other bias	High risk	Baseline risk for foot ulceration: no data provided Adherence: intervention mean number of podiatry visits 4.7 in first year. After first and before seventh follow‐up year at least 1 podiatry visit in 82.3% of people in intervention and in 49.7% in control Co‐interventions: podiatry care was provided to intervention group people only

BMI = body mass index, CI = confidence interval, HbA1c = glycated haemoglobin, HR = hazard ratio, ITT = intention to treat, PVD = peripheral vascular disease, RA = risk assessment, RCT = randomised controlled trial, RR = risk ratio, SD = standard deviation, SDSCA = Summary of Diabetes Self‐Care Activities.