Multidisciplinary Treatments, Patient Characteristics, Context of Care, and Adverse Incidents in Older, Hospitalized Adults

Table 1

Independent variable definitions.

Variable name	Variable definition and coding source	Variable type and operational definition
Patient characteristics
Gender	The behavioral, cultural, and psychological traits typically associated with one’s sex.	Categorical: M = male, F = female, D = deferred (not determined yet).
Age	Age when patient was admitted to hospital.	Continuous; measured in years.
Occupation	Activity pursued as a livelihood.	Categorical: 1 = retired, 2 = working/employed, 3 = homemaker, 4 = not retired/not employed.
Ethnicity	Race: a group of people united by certain characteristics.	Categorical: 1 = Caucasian, 2 = all others (includes the categories of African American, Hispanic, Native American/Alaskan Native; Asian/Pacific Islander, and other).
Site admitted from	The site from which the patient was admitted to the hospital.	Categorical: 1 = hospital, 2 = care facility, 3 = home/other routine admission.
Clinical conditions
Primary medical diagnosis	The primary medical diagnoses came from the International Classification of Diseases, 9th Revision (Clinical Modification) (ICD-9-CM) codes [10] found in MRA diagnostic codes and have been classified into Clinical Classification Software (CCS) categories [11].	Dichotomous:0 = no, the diagnosis (i.e., as represented by a particular CCS category) is not the primary diagnosis, 1= yes, the diagnosis (i.e., as represented by a particular CCS category) is the primary diagnosis.
Severity of illness	A rating assigned to each hospital visit retrospectively to measure organ system loss of function or physiological decompensation. Coded using the All Patient Refined Diagnosis Related Groups (APR-DRGs) [12].	Integral:1 = mild, 2 = moderate, 3 = major, 4 = severe.
Comorbid conditions	Clinical conditions that exist before admission are not related to the principal reason for hospitalization and are likely to be significant factors influencing mortality and resource use [13].	Each of 30 comorbid medical conditions is treated as a dichotomous variable:0 = no, the condition was not present at time of admission,1 = yes, the condition was present at the time of admission.
Past hospitalizations during the study period	The number of previous hospitalizations that the patient experienced during the study period.	Integral: 0 = no previous hospitalizations, 1 = 1 previous hospitalization, 2 = 2 previous hospitalizations, 3 = 3 previous hospitalizations, and 4 = 4 or greater previous hospitalizations.
Context of care variables
Average CGPR-RN	For an entire visit, the average number of all hourly CGPR RN values [14] for the visit. The hourly CGPR RN values serve as the building blocks for this variable and are calculated by dividing the total RN hours for a one-hour period by the total patient hours for that same 1-hour time period.	For each 1 hour of the visit, calculate:total no. of RN hours for a 1-hour time periodtotal no. of patient hours for that same hourand then calculate:sum of hourly CGPR RN values for the entire hospitalizationtotal hours of hospitalization.
Nursing skill mix	Proportion of RNs to all nursing direct caregivers for a specified time period.	The average of the hourly RN values was obtained by dividing the total number of RNs for all hours by the total number of hours for the hospital visit. The average of the total caregiver hours was obtained by dividing the total number of caregivers for all hours by the total number of hours for the hospital visit.
CGPR RN dip variable	The extent to which the minimum amount of RN care falls below the average of all the hourly CGPR values for the entire visit. This represents the variability in the amount of RN care that is available, specifically the extent to which the amount of RN care available drops below the average amount of RN care available for the hospital visit.	Average CGPR-RN minus the average of the three lowest hourly CGPR RN values for the visit. The larger this value is, the more the minimum CGPR RN fell below the average for the visit.
Number of units resided on	The sum of the number of units on which treatment was provided to an individual patient during the course of the hospital visit.	Integral:1 = 1 unit, 2 = 2 units, 3 = 3 units, 4 = 4 units, 5 = ≥ 5 units.
Treatments
Number of medical treatments	Medical procedures performed during a hospital visit to diagnose and treat a given patient based upon a physician’s judgment and knowledge to promote or maintain health, cure diseases, or palliate incurable diseases. Coded using ICD-9-CM codes [10] from the medical record abstraction (MRA) and regrouped into multilevel CCS categories [11].	Continuous: a count on the number of medical treatments that were performed during the course of a hospital visit, this is not the number of unique medical treatments.
Types of medical treatments	Any procedure that, based upon a physician’s judgment and knowledge, is necessary to promote or maintain health, cure diseases, or palliate disease processes that are incurable. Coded using ICD-9-CM codes [10] from the MRA and regrouped into multilevel CCS categories [11].	Dichotomous:0 = no the treatment (i.e., as represented by a particular CCS category) was not received during hospitalization, 1 = yes, the treatment (i.e., as represented by a particular CCS category) was received at least once during hospitalization.
Number of unique medications	The count per visit of unique generic drug names for drugs administered at least once during a visit. Medication types were coded using the American Hospital Formulary Service’s (AHFS) three-level system [9].	Continuous:a count of the number of unique medications delivered during a hospital visit.
Pharmacy treatments	Medications used in the care of patients during a hospital visit. Medication types were coded using the AHFS three-level system [9].	Dichotomous:0 = no medication from the AHFS class was administered during the hospital visit,1 = yes, at least one medication from the AHFS class was administered at least once during the hospital visit.
Number of unique nursing treatments	The number of unique nursing treatments delivered during the hospital visit. Captured using NIC [8, 15].	Continuous:a count of the unique nursing treatments delivered during the hospital visit.
Nursing treatments	Any treatment nursing personnel performed to enhance patient outcomes. Captured using NIC [8, 15].	Categorical: (multilevel) [16].(a) NIC used in >95% of visits; divided into quartiles 1 = 1–25% (lowest use rates, includes 0 use), 2 = 26–50% quartile, 3 = 51–75% quartile, 4 = 76–100% quartile (highest use rates).(b) NIC used in ≤95% and >5% of visits; divided into thirds: 0 = NIC not used, 1 = 1–33% lowest third, 2 = 34–67% middle third, 3 = 68–100% top third.(c) NIC used in <5% of the visits 0 = did not receive the NIC, 1 = did receive the NIC.