Simpson 1990.
| Methods |
Parallel randomised controlled clinical trial Randomisation ratio: 1:1 Superiority design |
|
| Participants |
Inclusion criteria: people with type 2 diabetes on insulin therapy, inadequate controlled (fasting glucose > 8.0 mmol/L Exclusion criteria: not stated Diagnostic criteria: not stated |
|
| Interventions |
Number of study centres: 1 Treatment before study: intervention: 36 (10‐62) insulin , placebo: insulin 31 (14‐112) U/day. Insulin regimen: once (n = 5) or twice daily (n = 15) Titration period: 2 months minimum run‐in period in which oral medication was stopped |
|
| Outcomes | Primary outcome(s) (as stated in the publication): serum and urinary glucoses, HbA1c, urinary C‐peptide, insulin dose, number of tablets prescribed, compliance | |
| Study details |
Total study duration: 2 months run‐in and 8 weeks intervention Run‐in period: 2 months Study terminated early (for benefit/because of adverse events): no |
|
| Publication details |
Language of publication: English Funding source: Farmaitalia Publication status: peer‐reviewed journal |
|
| Stated aim of study | Quote from publication: "To assess the relative contribution of endogenous insulin secretion and peripheral insulin sensitivity when SU was given in combination with insulin to 'secondary failure' type 2 diabetes patients." | |
| Notes | ||
| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Low risk | Quote from publication: "patients were randomised to receive either glipizide 10 mg twice daily or placebo, in addition to usual insulin" |
| Allocation concealment (selection bias) | Unclear risk | Comment: not possible to judge whether the allocation to the intervention and control group was concealed |
| Blinding of participants and personnel (performance bias) Adverse events | Low risk | Quote from publication: "The treatment was blind to both the patient and investigators" |
| Blinding of participants and personnel (performance bias) HbA1c, FPG, lipids | Low risk | Quote from publication: "The treatment was blind to both the patient and investigators" |
| Blinding of participants and personnel (performance bias) Insulin dose | Low risk | Quote from publication: "The treatment was blind to both the patient and investigators" |
| Blinding of outcome assessment (detection bias) Adverse events | Unclear risk | Comment: unclear if the outcome assessor was blinded |
| Blinding of outcome assessment (detection bias) HbA1c, FPG, lipids | Unclear risk | Comment: unclear if the outcome assessor was blinded |
| Blinding of outcome assessment (detection bias) Insulin dose | Unclear risk | Comment: unclear if the outcome assessor was blinded |
| Incomplete outcome data (attrition bias) Adverse events | Low risk | Comment: data on weight gain were collected and reported |
| Incomplete outcome data (attrition bias) HbA1c, FPG, lipids | Low risk | Comment: outcome data were collected and reported |
| Incomplete outcome data (attrition bias) Insulin dose | Low risk | Comment: data on insulin dose were collected and reported |
| Selective reporting (reporting bias) | Low risk | Comment: all outcomes of interest were reported |
| Other bias | Unclear risk | Comment: funded by a pharmaceutical company |