3 Evidence

Clinical evidence

The evidence for Curos is limited in quantity and quality and may not be generalisable to NHS practice


The clinical evidence for Curos comprises 6 uncontrolled before-and-after studies and 9 unpublished abstracts. Overall, the before-and-after studies reported a reduction in bloodstream infections but were of low quality and have a high risk of potential bias. All studies introduced Curos at the same time as elements of education, disinfection protocol awareness and audit, all of which may have affected the outcomes. The studies used inconsistent classifications and definitions of bloodstream infections. They also included different populations, which makes it difficult to accurately compare results. The 9 unpublished abstracts describe studies done in a range of settings, but the details are limited. There was no evidence for the use of Curos in community settings. Only 1 of the before-and-after studies and 2 of the abstracts were done in the UK, which may limit the generalisability of the results to NHS practice. For full details of the clinical evidence, see sections 2.2 and 2.3 of the assessment report.

The meta-analysis of 4 studies is likely to be imprecise because it is based on low quality evidence


The company submitted 2 meta-analyses: the first used data from 4 studies that reported rates of central line-associated bloodstream infection, and the second used data from 2 of the same 4 studies which were done in an intensive care setting. Because of the low quality of the individual studies and the differences between them, the external assessment centre (EAC) concluded that the meta-analysis of the 4 studies was at risk of serious imprecision. However, the results of both meta-analyses were used in the cost modelling because no better estimates were available (see appendix E of the assessment report for further details).

Cost evidence

The company's cost model shows that using Curos is cost saving in both general hospital and intensive care populations


The company presented a decision-tree model with 2 main branches: 1 for Curos and 1 for standard care (alcohol wipes). Patients in each branch can develop central line-associated bloodstream infections. Based on the company's 2 meta-analyses, the model can report results for either the whole hospital population or only the intensive care population. The EAC agreed with the overall structure, noting that there were no changes to the model care pathway other than exchanging 1 method of disinfecting for another. The company's model showed that using Curos saves around £28 per person in the general hospital population and around £134 per person in the intensive care population. For full details of the cost evidence, see section 4 of the assessment report.

The EAC's revised model shows that Curos is only cost saving in the general hospital population


The EAC made some changes to the model, including increasing the number of needleless connector ports in the intensive care setting from 10 to 12 (based on expert advice). The EAC also reduced the nurse time for standard care from 45 seconds to 15 seconds (equal to Curos); it considered that nurses would use the 30-second drying time of alcohol wipes for other tasks, and so this should not be considered as time saved when using Curos. The EAC's revised model showed that using Curos saves around £17 in the general hospital population, but incurs additional costs of around £94 per person in the intensive care population.

Sensitivity analyses suggest that Curos could be cost saving in the intensive care population but any results are uncertain


The EAC's sensitivity analyses showed that the main driver of cost savings in the general hospital population was baseline infection rate. No main driver of cost savings was identified in the intensive care population, but a threshold analysis showed that Curos could be cost saving in this population if there were a high enough difference in infection incidence between Curos and standard care (an incidence rate ratio of 0.75). However, any results are uncertain because the analyses are informed by data from the clinical evidence, which is of low quality.