Casner 1988.
| Methods |
Parallel randomised controlled clinical trial Randomisation ratio: 1:1 Superiority design |
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| Participants |
Inclusion criteria: people with non‐insulin‐dependent diabetes previously treated with an oral hypoglycaemic agent, currently receiving at least 25 U insulin/day with a fasting blood glucose value of 140 mg/dL or greater. Exclusion criteria: history of allergic reactions to sulphonylurea therapy or a serious debilitating disease that would limit ability to participate in the study Diagnostic criteria: NDDG 1979 |
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| Interventions |
Number of study centres: 1 Treatment before study: insulin: intervention 65.9 U/day and control 66.9 U/day Titration period: variable |
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| Outcomes | Primary outcome(s) (as stated in the publication): glycaemic control (HbA1c, oral glucose tolerance test, fasting blood glucose), side effects, C‐peptide, insulin dose, weight | |
| Study details |
Total study duration: 1 year Run‐in period: variable Study terminated early (for benefit/because of adverse events): no |
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| Publication details |
Language of publication: English Funding source: Upjohn Company and an intramural grant from Texas Tech Health Sciences Center Publication status: peer‐reviewed journal |
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| Stated aim of study | Can the combination of a sulphonylurea and insulin improve glycaemic control? If this is true, can it be done with lower doses of exogenous insulin? Can the effect be maintained over a long period of time? | |
| Notes | ||
| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Unclear risk | Comment: not possible to judge whether the sequence generation was adequate |
| 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 | High risk |
Quote from publication: "Patients and physicians were blinded regarding laboratory results and study medication but not on insulin" Comment: so patients were not blinded for their weight gain (this is the only adverse event mentioned) |
| Blinding of participants and personnel (performance bias) HbA1c, FPG, lipids | Low risk |
Quote from publication: "Patients and physicians were blinded regarding laboratory results and study medication but not on insulin" Comment: |
| Blinding of participants and personnel (performance bias) Insulin dose | High risk | Quote from publication: "Patients and physicians were blinded regarding laboratory results and study medication but not on insulin" |
| Blinding of outcome assessment (detection bias) Adverse events | Unclear risk | Comment: it is unclear if the outcome assessment was blinded |
| Blinding of outcome assessment (detection bias) HbA1c, FPG, lipids | Unclear risk | Comment: it is unclear if the outcome assessment was blinded |
| Blinding of outcome assessment (detection bias) Insulin dose | Unclear risk | Comment: it is unclear if the outcome assessment was blinded |
| Incomplete outcome data (attrition bias) Adverse events | Low risk | Comment: data on weight gain was reported for both groups |
| Incomplete outcome data (attrition bias) HbA1c, FPG, lipids | Low risk | Comment: data were reported for both groups |
| Incomplete outcome data (attrition bias) Insulin dose | Low risk | Comment: data were reported for both groups |
| Selective reporting (reporting bias) | Low risk | Comment: data which was collected was also reported |
| Other bias | Low risk | Comment: no other concerns |