| Methods |
Single‐centre RCT (USA) |
| Participants |
Quote: "in the absence of fever or suspected infection, and after recovery of all hematologic side effects of chemotherapy, all patients admitted to the gynaecologic oncology service requiring central venous access for medical or surgical conditions were eligible.” |
| Interventions |
CVCs with silver‐impregnated cuff versus standard uncoated CVCs |
| Outcomes |
Clinical sepsis, catheter colonization and adverse effects |
| Notes |
Sources of funding: not stated |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Low risk |
Randomization was performed “based on a table of random numbers” |
| Allocation concealment (selection bias) |
Low risk |
Quote: “… randomization did not occur until after informed consent was obtained." |
| Blinding of participants and personnel (performance bias)
All outcomes |
High risk |
It was not stated whether the catheters were identical in appearance or any blinding occurred, although blinding appeared unlikely as the study catheter had a different cuff compared to the control catheter, and an additional incision had to be made when inserting the study catheter |
| Blinding of outcome assessment (detection bias)
Microbiological outcomes like catheter colonization |
Unclear risk |
It was unclear whether the assessors of the microbiological outcomes were blinded to the status of the catheter samples |
| Blinding of outcome assessment (detection bias)
Clinical outcomes like CRBSI |
High risk |
It was not stated whether the catheters were identical in appearance or any blinding occurred, although blinding appeared unlikely as the study catheter had a different cuff compared to the control catheter, and an additional incision had to be made when inserting the study catheter |
| Incomplete outcome data (attrition bias)
All outcomes |
Low risk |
9/142 (6.3%) catheters were excluded from the analysis. The reasons for exclusion were inability to access the subclavian vein (5 participants), operative findings of peritonitis or intra‐abdominal abscess (3 participants) and inadvertent catheter removal during transport (1 participant). The authors did not provide the number excluded from each groups. In view of the relatively high event rates for the outcomes in relation to the number excluded, we felt that the study had a low risk of attrition bias |
| Selective reporting (reporting bias) |
High risk |
All the outcomes specified in the Methods were reported in the Results. However, the adverse effects ‐ including pneumothorax and thrombosis ‐ were only reported as the overall rate and not the numbers in each group, and therefore the data could not be included in the meta‐analysis |
| Other bias |
Unclear risk |
It was unclear whether randomization was effective in this study, as the assigned groups did not appear to be prognostically comparable: the Vitacuff group had more ICU cases, more cases needing assisted ventilation, venous blood sampling, hyperalimentation and broad spectrum antibiotics use |
