Table 2 The four key elements of study design applied to three systematic reviews of transfusion literature
From: Observational studies - should we simply ignore them in assessing transfusion outcomes?
Study | 1. Patients | 2. Intervention/Exposure | 3. Outcomes | 4. Study methods |
|---|---|---|---|---|
Efficacy of red blood cell transfusion in the critically ill: A systematic review of the literature | Cardiac Patients | Comparison between patients transfused red blood cells to patients not transfused red blood cells | Mortality | Observational Studies |
Critical Care Patients | Infection | |||
Orthopaedics | Multiorgan Dysfunction | |||
Trauma | Acute Respiratory Distress | |||
General Surgery | ||||
Neurosurgery | ||||
Transfusion thresholds and other strategies for guiding Transfusion thresholds and other strategies for guiding red blood cell transfusion (Cochrane Review) | Cardiac Patients | Comparison of patients assigned to a liberal transfusion strategy to patients assigned to a restrictive transfusion strategy | Mortality | Randomized Controlled Trials |
Critical Care Patients | Infection | |||
Orthopaedics | Length of Stay | |||
GI Bleeding | Function and Fatigue | |||
Trauma | Cardiac events | |||
Vascular | Myocardial infarction | |||
Haematology | Pulmonary oedema | |||
Stroke | ||||
Pneumonia | ||||
Thromboembolism | ||||
Rebleeding | ||||
Renal failure | ||||
Mental confusion | ||||
HealthCare–Associated Infection After Red Blood Cell Transfusion: A Systematic Review and Meta-analysis | Cardiac Patients | Comparison of patients assigned to a liberal transfusion strategy to patients assigned to a restrictive transfusion strategy | Infection | Randomized Controlled Trials |
Critical Care Patients | ||||
Orthopaedics | ||||
GI Bleeding | ||||
Post Partum | ||||
Sickle Cell |