Table 2.

Adverse Event (AE) Rates for the Baylor Health Care System (BHCS) Eight Acute Care Hospitals (January 2007–December 2011)

	Total*			Hospital Acquired			Present on Admission
	AEs/1,000 Pt-Days	AEs/100 Discharges	≥1 AE (%)	AEs/1,000 Pt-Days	AEs/100 Discharges	≥1 AE (%)	AEs/1,000 Pt-Days	AEs/100 Discharges	≥1 AE (%)
BHCS	61.4	38.1	32.1	38.1	23.6	20.7	23.3	14.4	12.9
BHCS (weighted)†	59.6	38.9	32.5	37.4	24.6	21.3	22.2	14.3	12.7

Note. Weighted values were based on the relative volume of patients meeting the inclusion criteria.

^*Records from 9,017 patient encounters were reviewed from a total of 315,274 eligible encounters. Those records involved a total of 55,916 patient-days, from a total of 2,168,956 patient-days for admissions meeting the inclusion criteria.

^†Weighted according to the contributions of each of the eight acute care hospitals, based on the relative facility size with respect to the population that was eligible to be sampled, to account for our data collection process’s relative oversampling of small hospitals and undersampling of the largest hospital (Kennerly et al. 2013).