Altuntas 2003

Methods	Parallel randomised controlled clinical trial, randomisation ratio 1:1:1
Participants	Inclusion criteria: type 2 diabetes, secondary OAD failure (defined as initial stabilization of BG control for at least 6 months followed by lack of control with max. sulphonylurea dose and full compliance regarding diet) Exclusion criteria: not reported Diagnostic criteria: ADA 1997
Interventions	Number of study centres: not reported Treatment before study: OADs Titration period: 6‐month treatment period
Outcomes	Outcomes reported in abstract of publication: HbA1c levels, plasma glucose levels (10‐day profile), triglyceride levels, hypoglycaemic episodes
Study details	Run‐in period: not reported Study terminated early: no Trial register ID: not reported
Publication details	Language of publication: English Funding: not reported Publication status: full article in a peer review journal
Study aim for study	Quote from publication: "The aim was to assess the effects of three different insulin regimes (group 1: lispro insulin + NPH insulin, group 2: lispro insulin + metformin, and group 3: regular insulin + NPH insulin) on overall glycaemic control and metabolic parameters in type 2 diabetic patients with secondary oral anti‐diabetic drug failure"
Notes	HbA1c was not shown because of inconsistent baseline HbA1c data Group 2 was not included in our systematic review because a different therapy regiment (insulin lispro + metformin) was used in this group, which did not fulfil our inclusion criteria
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote from publication: "Patients were randomly assigned to three different groups" Comment: not enough details
Allocation concealment (selection bias)	Unclear risk	Comment: not reported
Blinding of participants and personnel (performance bias) HbA1c	Unclear risk	Quote from publication: "open‐label" Comment: investigator‐reported outcome measurement
Blinding of participants and personnel (performance bias) Adverse events	High risk	Quote from publication: "open‐label" Comment: self‐reported and investigator‐reported outcome measurement
Blinding of outcome assessment (detection bias) HbA1c	Unclear risk	Quote from publication: "open‐label" Comment: investigator‐reported outcome measurement
Blinding of outcome assessment (detection bias) Adverse events	High risk	Quote from publication: "open‐label" Comment: self‐reported and investigator‐reported outcome measurement
Incomplete outcome data (attrition bias) HbA1c	Low risk	Comment: all participants completed the 6‐month trial period
Incomplete outcome data (attrition bias) Adverse events	Unclear risk	Comment: number of analysed participants unclear
Selective reporting (reporting bias)	High risk	Comment: outcome reporting bias for all hypoglycaemic episodes according to ORBIT (see Appendix 8)
Other bias	High risk	Comment: inconsistencies regarding reported outcomes in publication, no definition of primary outcome, no sample size calculation