Nye 1990.
| Methods | Randomisation: parallel, 3 groups (omega 3 vs olive oil vs aspirin and dipyridamole), 1 year Risk of bias: moderate or high |
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| Participants | People undergoing PTCA N: 36 intervention, 37 control (also 35 allocated to arm 3, aspirin and dipyridamole) Level of risk for CVD: high (people undergoing angioplasty) Men: 78% intervention, 76% control Mean age in years (SD): 54 (8) intervention, 55 (8) control years Age range: unclear Smokers: unclear Hypertension: unclear Medications taken by at least 50% of those in the control group: not reported Medications taken by 20%‐49% of those in the control group: not reported Medications taken by some, but less than 20% of the control group: not reported Location: New Zealand Ethnicity: unclear |
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| Interventions | Type: supplement (capsules) Comparison: EPA vs MUFA Intervention: MaxEPA capsules 12/d (2.2 g EPA). Dose: 2.2 g/d EPA Control: olive oil capsules, 12/d, identical to MaxEPA. Both capsules included vitamin E Compliance: no data Length of intervention: 12 months |
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| Outcomes | Main study outcome: angina, restenosis Dropouts: none Available outcomes: angina, interventions, lipids (Nil death) Response to contact: no |
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| Notes | Study funding: Medical Research Council of New Zealand and Scherer Ltd (who supplied MaxEPA and the olive oil capsules) | |
| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Unclear risk | Quote: "randomly divided without exclusions into 3 groups" |
| Allocation concealment (selection bias) | Unclear risk | Unclear, no further info |
| Blinding of participants and personnel (performance bias) All outcomes | Unclear risk | States that placebo capsules were identical to the MaxEPA, and "neither the patient nor the attending cardiologist knew which capsules were being used" (but no masking of taste was reported, and participant guesses as to allocation were not reported) |
| Blinding of outcome assessment (detection bias) All outcomes | Low risk | Quote: "neither the patient, nor the attending cardiologist knew which capsules were being used" ... "Angioplasty was repeated electively at one year or before where symptoms recurred, and assessed without knowledge of the patient's treatment group." |
| Incomplete outcome data (attrition bias) All outcomes | Unclear risk | Some participants were lost to follow‐up and reasons for this were unclear |
| Selective reporting (reporting bias) | Unclear risk | No protocol or trials registration found |
| Attention | Low risk | No suggestion of attention bias, symptomatic patients were reviewed between scheduled visits, otherwise all on the same schedule |
| Compliance | Unclear risk | No data |
| Other bias | Low risk | No further bias noted |