Cohort Characteristics by Outcome Group (N = 8,216)
| Characteristic | Case Group 1: ED Visit (n = 3,809) | Case Group 2: Inpatient Visit (n = 2,627) | Controls: No Second Hospital Visit (n = 1,780) | P Value |
|---|---|---|---|---|
| Gender, No. (%) | <.001b | |||
| Female | 2,441 (64) | 1,661 (63) | 909 (51) | |
| Male | 1,367 (36) | 966 (37) | 871 (49) | |
| NA | 1 (0) | 0 (0) | 0 (0) | |
| Age, y, No. (%) | <.001b | |||
| 18-49 | 1,411 (37) | 1,111 (42) | 838 (47) | |
| ≥50 | 2,398 (63) | 1,516 (58) | 942 (53) | |
| NA | 0 (0) | 0 (0) | 0 (0) | |
| Ethnicity, No. (%) | .003a | |||
| Hispanic | 2,498 (66) | 2,005 (76) | 1,261 (71) | |
| Non-Hispanic | 465 (12) | 370 (14) | 302 (17) | |
| NA | 846 (22) | 252 (10) | 217 (12) | |
| Insurance status, No. (%) | <.001b | |||
| Medicaid | 509 (13) | 368 (14) | 205 (12) | |
| Medicare | 1,038 (27) | 616 (23) | 338 (19) | |
| Private | 1,095 (29) | 831 (32) | 517 (29) | |
| Self-pay | 484 (13) | 293 (11) | 511 (29) | |
| Uninsured | 323 (8) | 302 (11) | 104 (6) | |
| NA | 360 (9) | 217 (8) | 105 (6) | |
| HIE accessed, No. (%) | <.001b | |||
| Yes | 107 (3) | 60 (2) | 103 (6) | |
| No | 3,702 (97) | 2,567 (98) | 1,677 (94) | |
| Patient days, median (IQR) | 43 (10-108) | 26 (2-88) | 290 (207-343) | <.001b |
ED = emergency department; HIE = health information exchange; IQR = interquartile range; NA = not available.
Note: Outcome groups were based on whether a patient visited an ED or was rehospitalized (inpatient visit) for the same or similar symptoms as indicated by the ICD-10 codes from first hospital discharge.
↵a Significance level 0.01
↵b Significance level 0.001