Effectiveness of visual inspection compared with non-microbiologic methods to determine the thoroughness of post-discharge cleaning

BACKGROUND: Published data to date have provided a limited comparison between non-microbiologic methods—particularly visual inspection—and a microbiologic comparator to evaluate the effectiveness of environmental cleaning of patient rooms. We sought to compare the accuracy of visual inspection with other non-microbiologic methods of assessing the effectiveness of post-discharge cleaning (PDC). METHODS: Prospective evaluation to determine the effectiveness of PDC in comparison to a microbiologic comparator. Using a highly standardized methodology examining 15 high-touch surfaces, the effectiveness of PDC was evaluated by visual inspection, the removal of fluorescent marker (FM) placed prior to room occupancy, quantification of adenosine triphosphate (ATP) levels, and culture for aerobic colony counts (ACC). RESULTS: Twenty rooms including 293 surfaces were sampled in the study, including 290 surfaces sampled by all four methods. ACC demonstrated 72% of surfaces to be microbiologically clean. Visual inspection, FM, ATP demonstrated 57%, 49%, and 66% of surfaces to be clean. Using ACC as a microbiologic comparator, the sensitivity of visual inspection, FM, and ATP to detect a clean surface were 60%, 51%, and 70%, respectively; the specificity of visual inspection, FM, and ATP were 52%, 56%, and 44%. CONCLUSIONS: In assessing the effectiveness of PDC, there was poor correlation between the two most frequently studied commercial methods and a microbiologic comparator. Visual inspection performed at least as well as commercial methods, directly addresses patient perception of cleanliness, and is economical to implement.