Hospital hand hygiene opportunities: Where and when (HOW2)? The HOW2 Benchmark Study

Background: Measurement and monitoring of health care workers' hand hygiene compliance (ie, actions/opportunities) is a key component of strategies to eliminate hospital-acquired infections. Little data exist on the expected number of hand hygiene opportunities (HHOs) in various hospital settings, however. The purpose of this study was to estimate HHOs in 2 types of hospitals-large teaching and small community-and 3 different clinical areas-medical-surgical intensive care units, general medical wards, and emergency departments. Methods: HHO data were collected through direct observations using the World Health Organization's monitoring methodology. Estimates of HHOs were developed for 12-hour AM/PM shifts and 24-hour time frames. Results: During 436.7 hours of observation, 6,640 HHOs were identified. Estimates of HHOs ranged from 30 to 179 per patient-day on inpatient wards and from 1.84 to 5.03 per bed-hour in emergency departments. Significant differences in HHOs were found between the 2 hospital types and among the 3 clinical areas. Conclusion: This study is the first to use the World Health Organization's data collection methodology to estimate HHOs in general medical wards and emergency departments. These data can be used as denominator estimates to calculate hand hygiene compliance rates when product utilization data are available.