Tinsel 2013.

Methods	Study design: cluster‐randomized trial Unit of allocation: practice Unit of analysis: patient Power calculation: done
Participants	Care setting: primary care and ambulatory care; Germany Health professionals: number unknown; general practitioners; fully trained Patients: 1120; hypertension; male and female
Interventions	Multifaceted intervention: distribution of educational material, educational meeting Quote: "Those GPs who had been allocated to the intervention group took part in an SDM training programme... which had been evaluated in various studies...The training included the following elements: (1) information on arterial hypertension, (2) physician‐patient communication and risk communication, (3) the process steps of SDM, (4) motivational interviewing [40,41], (5) introduction of a decision table listing options to lower CVR, and (6) use of case vignettes for role plays simulating physician‐patient consultations. Additionally, we recommended implementing a cardiovascular risk calculator for GPs which included elements of SDM... Furthermore we delivered patient information flyers...to the GPs of the intervention group." page 3 Usual care (control) Quote: "GPs of the control group treated their patients as usual." page 3
Outcomes	SDM‐Q‐9 (continuous)
Notes	Additional information Number of approached practices (eligible): 115 Number of patients per practices: 32.5 in intervention group, 29.9 in control group
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Comment: not reported in the paper.
Allocation concealment (selection bias)	Low risk	Comment: randomization at the GP practice level.
Blinding (performance bias and detection bias) Participant‐reported outcome	Low risk	Quote: "The patients were blinded to the allocation of the intervention (single‐blinded study)." page 3 column 2 paragraph 1
Incomplete outcome data (attrition bias) Participant‐reported outcome	Unclear risk	Comment: lost to follow‐up at T3 and non response to outcomes is higher in higher in control group than in intervention group. Was the follow up in the 2 groups comparable? Are the principal reason for missing data related to outcomes (patient desire)? What is the pattern of reasons for discontinuation across groups? There is no clear pattern of missing data.
Selective reporting (reporting bias)	Low risk	Commment: tables 1,2,3 and study protocol.
Other bias	Low risk	Comment: no evidence of other risk of biases.
Baseline measurement? Participant‐reported outcome	Low risk	Comment: see table 2.
Protection against contamination?	Low risk	Comment: randomization at the GP practice level.
Baseline characteristics patients	Low risk	Comment: reported and similar (See table 2).
Baseline characteristics healthcare professionals	Unclear risk	Comment: no information about professionals.