Table 3. Studies that compared models within a population.

Study and models compared	Model description	C-statistic (95% CI or SE if reported)
Halfon, 200613
Nonclinical model	Age, sex, prior utilization	0.67
Modified Charlson score based model	Charlson score60 plus prior utilization	0.69
Modified SQLape model61	Complex administrative model combining comorbidity, age, and utilization data into 49 risk categories	0.72
Hammill 201118
Claims-only model	CMS administrative heart failure model15	0.59
Claims-clinical model	CMS heart failure model + serum creatinine, serum sodium, hemoglobin, systolic blood pressure	0.60
Allaudeen, 201134
PRA*32	Age, sex, self-rated health, availability of informal caregiver, coronary disease, diabetes, hospital admission within past year, prior utilization	0.56 (0.44-0.67)
Prediction by physician	Interns, residents, and attending physicians predicted chance of readmission based on overall evaluation of patient	0.58-0.59 (0.46-0.70)
Prediction by non-physician provider	Nurses and case managers predicted chance of readmission based on overall evaluation of patient	0.50-0.55 (0.38-0.67)
Amarasingham, 201024
ADHERE mortality model	Blood urea nitrogen, creatinine, and systolic blood pressure	0.56 (0.54-0.59)
CMS heart failure model15	Complex administrative comorbidity model consisting of age, sex, and 35 hierarchical condition categories	0.66 (0.63-0.68)
Tabak mortality model62	Age, 17 lab and vital sign variables within 24 hours of hospital presentation	0.61 (0.59-0.64)
Electronic readmission model	Includes Tabak mortality score, history of depression or anxiety, single status, sex, residential stability, Medicare status, residence census tract in lowest socioeconomic quintile, history of confirmed cocaine use, history of missed clinic visit, use of a health system pharmacy, number of prior admissions, presented to emergency department between 6 am and 6 pm for index admission.	0.72 (0.70-0.75)
Coleman, 200427
Administrative model	Age, sex, prior utilization, Medicaid status, Charlson score,60 heart disease, cancer, diabetes	0.77
Administrative + self-report model	Administrative model + self-rated health, ADL assistance need, visual impairment, functional status	0.83
Naessens, 199223
Modified Health Care Financing Administration (HCFA) mortality model63	Age, sex, 16 DRG, and 8 comorbidities	0.59 (SE=0.01)
HCFA + COMPLEX	Complicated administrative model incorporating DRG based disease staging and number of body systems affected + HCFA	0.61 (SE=0.01)

Abbreviations: ADHERE denotes Acute Decompensated Heart Failure Registry; CI, Confidence Interval; CMS, Center for Medicaid and Medicare Services; COMPLEX, a measurement of comorbidity and disease severity;²³ HCFA, Health Care Financing Administration; IDI, Integrated Discrimination Improvement; PRA, Probability of Repeated Admission; SE, Standard Error.

^*Variables were obtained from chart abstraction, whereas original PRA instrument is based on patient surveys.