Table 1:
The List of Variables Collected from Multiple Sources
| Variable Name | Variable Description |
|---|---|
| Age (EI) | Patient’s age |
| Gender (EI) | Patient’s gender |
| Race (EI) | Patient’s race |
| Ethnicity (EI) | Patient’s ethnicity |
| Insurance type (EI) | Patient’s insurance type (eg, commercial, Medicare, and self-pay) |
| Arrival means (EI) | The arrival means of the patient (eg, walk in, by private car and other) |
| Arrival time (EI) | The time interval in which the patient arrived (at 2-h increment) |
| Arrival season (EI) | The season of the patient visit (spring, summer, autumn, winter) |
| Guardian presence (EI) | Is the patient escorted by his/her legal guardian? (yes/no) |
| Arrival complaint (EI) | Number of arrival complaints |
| Chief complaint (EI) | The category of the patient’s chief complaint (eg, abdominal pain) |
| Pain score (EI) | The pain score evaluated by the clinicians (normalized from 0 to 10) |
| Triage priority (EI) | Is this patient a triage priority? (yes/no) |
| Acuity (EI) | The acuity of the patient’s chief complaint (from 1 to 5: 1 indicating urgent complaint and 5 nonurgent complaint) |
| Length of stay (EI) | Patient’s length of stay (at 30-min increment) |
| Disposition (EI) | The disposition of the patient (admit, discharge, transfer, other) |
| Poor (SES) | Percentage of persons within a census tract at <100% poverty line |
| Extreme poor (SES) | Percentage of persons within a census tract at <50% poverty line |
| Unemployment (SES) | Unemployment rate within a census tract for persons ≥16 years in the workforce |
| Income (SES) | Median household income within a census tract |
| Occupied house (SES) | Percentage of housing units that are occupied within a census tract |
| House value (SES) | Median value of owner-occupied houses within a census tract |
| Crowded house (SES) | Percentage of households with ≥1 person per room within a census tract |
| Rent house (SES) | Percentage of households who rent their home within a census tract |
| Own car (SES) | Percentage of households who do not own a car within a census tract |
| Marriage (SES) | Percentage of persons aged ≥15 years who have never married within a census tract |
| Education (SES) | Percentage of persons aged ≥25 years with less than 12th grade education within a census tract |
| Complexity (CTC) | Amount of information provided to the patient (simple, moderate, complex) |
| Time required (CTC) | Length of time required for the trial (brief, moderate, extensive) |
| Invasiveness (CTC) | Level of invasiveness of the trial (from 1 to 5: 1 indicating noninvasive and 5 highly invasive) |
| Incentive (CTC) | Amount of compensation |
| Conductor (CTC) | Conductor of the clinical trial (patient, parent, CRC, nurse, and physician) |
| Trial type (CTC) | Type of the clinical trial (observation, intervention, other) |
| Randomization (CTC) | Is the trial a randomized trial? (yes/no) |
| Disease specific (CTC) | Is the trial a disease specific trial? (yes/no) |
| Multi-center (CTC) | Is the trial a multi-center trial? (yes/no) |
| Sample required (CTC) | Does the trial require samples (eg, blood sample)? (yes/no) |
| Follow-up visit (CTC) | Does the trial require follow-up visits? (yes/no) |
| Follow-up call (CTC) | Does the trial require follow-up calls? (yes/no) |
| Insurance restriction (CTC) | Does the trial only enroll Medicare or self-pay patients? (yes/no) |
| Sensitive topic (CTC) | Does the trial involve sensitive topics? (yes/no) |
“EI” in “Variable Name” indicates an “Encounter Information” variable, “SES” a socioeconomic status variable and “CTC” a clinical trial characteristics variable.