In 2018, the Clostridium difficile LabID event methodology changed so that hospitals doing 2-step tests, nucleic acid amplification test (NAAT) plus enzyme immunofluorescence assay (EIA), had their adjustment modified to EIA-based tests, and only positive final tests (eg, EIA) were counted in the numerator. We report the immediate impact of this methodological change at 3 Milwaukee hospitals.

Let P(c) = P(X 1 ≦ c 1, · ··, Xp ≦ cp ) for a random vector (X 1, · ··, Xp ). Bounds are considered of the form where T is a spanning tree corresponding to the bivariate probability structure and di is the degree of the vertex i in T. An optimized version of this inequality is obtained. The main result is that alwayṡ dominates certain second-order Bonferroni bounds. Conditions on the covariance matrix of a N(0,Σ) distribution are given so that this bound applies, and various applications are given.