Objective: (1)Develop an epidemiologically and statistically sound validation method; (2) apply the method to determine if each hospital is able to accurately identify which patients meet NHSN criteria for bloodstream infection (BSI) in their surveillance program.
Methods: A method and toolkit was developed in consultation with the Washington State HAI Program’s Advisory Committee. Based on the literature, 85% sensitivity & 98% specificity were determined to be achievable for BSI. An acceptance region of ± 15 percentage points was determined to be satisfactory precision, leading to calculation of 22 cases as sample size needed to estimate sensitivity & 22 to estimate specificity. This toolkit was distributed along with an evaluation form to 9 volunteer hospitals. The form addressed sample selection, time needed for completion, ease of use, difficulties encountered, and other comments.
Results: To date, 7 of 9 volunteers have provided feedback. None suggested revising language in the toolkit. 6 said they could complete the process without assistance; 1 asked for a site visit. Time to complete the process was consistent with our estimate of <6 hours (2 hospitals report 3-4 hours). Some were surprised to find their sensitivity was less than expected.
Conclusions: As a first step towards annual internal validation, our volunteers found this method to be feasible, practical and valuable.