Variable

Number Variable Name Description

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1 Identification number 1-113

2 Length of stay Average length of stay of all patients

in hospital (in days)

3 Age Average age of patients(in years)

4 Infection risk Average estimated probability of acquaring

infection in hospital (in percent)

5 Routine culturing ratio Ratio of number of cultures perfomed to

number of patients without signs or symptoms

of hospital-acquired infection,times 100

6 Routine chest X-ray ratio Ratio of number of X rays perfomed to number

of patients without signs or symptoms of

pneumonia,times 100

7 Number of beds Average number of beds in hospital during

study period

8 Medical school affiliation 1=Yes 2=No

9 Region Geographic region, where : 1=NE, 2=NC, 3=S

4=W

10 Average daily census Average number of patients in hospital per day

during study period

11 Number Average number of full-time equivalent

registered and licensed practical nurses

during study period (number full time plus one

half the number part time)

12 Available facilities Percent of 35 potential facilites and services

and services that are provided by the hospital

Reference: Special Issue,"The SENIC Project," American Journal of Epidemiology

111(1980),pp.465-653.