Table 1 List of variables and their corresponding category utilized in predicting 14-day unplanned readmission risk

Demographic

Age; Sex; Marital status; Religion; Education; Area of residence; Living alone

Health care utilization 6 months before index admission

Number of hospitalizations; Emergency department visits; Outpatient visits

Diagnoses 1 year before index admission

The total count of inpatient diagnoses; Number of unique inpatient diagnoses; Total counts of outpatient diagnoses; The number of unique outpatient diagnoses

Overall comorbidity and functional evaluation on index admission

The 3 major diagnoses of index admission; Charlson comorbidity index; Depression diagnoses; Consciousness level; Activities of daily living according to dependency level in mobility, dressing, feeding, toileting, and bathing; Nutrition status; Mood; Urinary incontinence; History of fall

Health care services–related variables during index admission

Index type of admission; Disease-Related Group of the index admission; Health education

One-time laboratory values recorded just before discharge

Hematocrit; White blood cell count; Red blood cell count; Mean corpuscular volume; Platelet count; Hemoglobin; Prothrombin time; Blood Urea Nitrogen; Creatinine; Aspartate Aminotransferase; Alanine Aminotransferase; Lactate Dehydrogenase; γ-glutamyl transferase; Total Bilirubin; Potassium; Calcium; Sodium; Albumin, C-reactive protein; Thyroid-Stimulating Hormone

Discharge-related factors

Registered in the discharge planning services; Vital signs recorded 24 h before discharge (systolic and diastolic blood pressure, pulse rate, respiratory rate, and body temperature); Department of discharge; Attending physician’s employee identity and years of experience; Number of discharge medication categories; Total number of tablets in discharge medication; Discharge destination; Discharge with pressure injury (or injuries); Types of catheters at discharge; Index hospital length of stay