Table 1. Demographic Characteristics of Participants by Study Group.
| Characteristic | Participants, No. (%) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Outbound telephone call only (n=390) | Text message plus outbound telephone call | Text message plus inbound telephone call | Total (n=16 045) | |||||||
| Standard messaging (n=1971) | Clinician endorsement (n=1985) | Scarcity (n=1977) | Endowment (n=1957) | Standard messaging (n=1918) | Clinician endorsement (n=1935) | Scarcity (n=1934) | Endowment (n=1978) | |||
| Age, mean (SD), y | 36.3 (11.6) | 36.7 (10.9) | 36.9 (10.6) | 36.9 (11.2) | 37.4 (11.6) | 36.7 (11.0) | 37.3 (11.2) | 36.7 (11.3) | 36.6 (10.9) | 36.9 (11.1) |
| Sex | ||||||||||
| Male | 155 (39.7) | 809 (41.1) | 792 (39.9) | 794 (40.2) | 842 (43.0) | 802 (41.8) | 830 (42.9) | 781 (40.4) | 822 (41.6) | 6627 (41.3) |
| Female | 235 (60.3) | 1162 (59.0) | 1193 (60.1) | 1183 (59.8) | 1115 (57.0) | 1116 (58.2) | 1105 (57.1) | 1153 (59.6) | 1156 (50.4) | 9418 (58.7) |
| Race | ||||||||||
| Asian or Pacific Islander | 26 (6.7) | 143 (7.3) | 161 (8.1) | 139 (7.0) | 157 (8.0) | 152 (7.9) | 153 (7.9) | 159 (8.2) | 150 (7.6) | 1240 (7.7) |
| White | 189 (48.5) | 1040 (52.8) | 1024 (51.6) | 1023 (51.8) | 1030 (52.6) | 991 (51.7) | 1017 (52.6) | 1009 (52.2) | 1022 (51.7) | 8345 (52.0) |
| Black | 127 (32.6) | 568 (28.8) | 597 (30.1) | 598 (30.3) | 575 (29.4) | 563 (29.4) | 550 (28.4) | 553 (28.6) | 575 (29.1) | 4706 (29.3) |
| >1 Race | 3 (0.8) | 13 (0.7) | 14 (0.7) | 9 (0.5) | 14 (0.7) | 15 (0.8) | 15 (0.8) | 8 (0.4) | 13 (0.7) | 104 (0.7) |
| Othera | 20 (5.1) | 77 (3.9) | 77 (3.9) | 96 (4.9) | 74 (3.8) | 76 (4.0) | 79 (4.1) | 84 (4.3) | 81 (4.1) | 664 (4.1) |
| Unknownb | 25 (6.4) | 130 (6.5) | 112 (5.6) | 112 (5.7) | 107 (5.5) | 121 (6.3) | 121 (6.3) | 121 (6.3) | 137 (6.9) | 986 (6.1) |
| Ethnicity | ||||||||||
| Hispanic or Latino | 26 (6.7) | 131 (6.7) | 114 (5.7) | 115 (5.8) | 126 (6.4) | 103 (5.4) | 131 (6.8) | 114 (5.9) | 107 (5.4) | 967 (6.0) |
| Not Hispanic or Latino | 352 (90.3) | 1785 (90.6) | 1824 (91.9) | 1829 (92.5) | 1800 (92.0) | 1781 (92.9) | 1761 (91.0) | 1779 (92.0) | 1815 (91.8) | 14 726 (91.8) |
| Unknownb | 12 (3.1) | 55 (2.8) | 47 (2.4) | 33 (1.7) | 31 (1.6) | 34 (1.8) | 43 (2.2) | 41 (2.1) | 56 (2.8) | 352 (2.2) |
| Patient portal status | ||||||||||
| Active | 308 (79.0) | 1587 (80.5) | 1618 (81.5) | 1601 (81.0) | 1613 (82.4) | 1547 (80.7) | 1582 (81.8) | 1561 (80.7) | 1645 (83.2) | 13 062 (81.4) |
| Not active | 82 (21.0) | 384 (19.5) | 367 (18.5) | 376 (19.0) | 344 (17.6) | 371 (19.3) | 353 (18.2) | 373 (19.3) | 333 (16.8) | 2983 (18.6) |
| Insurance coverage type | ||||||||||
| Commercial | 308 (79.0) | 1603 (81.3) | 1558 (78.5) | 1583 (80.1) | 1565 (80.0) | 1546 (80.6) | 1575 (81.4) | 1548 (80.0) | 1583 (80.0) | 12 869 (80.2) |
| Medicare | 5 (1.3) | 31 (1.6) | 34 (1.7) | 34 (1.7) | 39 (2.0) | 23 (1.2) | 36 (1.9) | 28 (1.5) | 25 (1.3) | 255 (1.6) |
| Medicaid | 59 (15.1) | 267 (13.6) | 290 (14.6) | 290 (14.7) | 288 (14.7) | 281 (14.7) | 247 (12.8) | 279 (14.4) | 282 (14.3) | 2283 (14.2) |
| Otherc | 2 (0.5) | 11 (0.6) | 17 (0.9) | 17 (0.9) | 11 (0.6) | 11 (0.6) | 22 (1.1) | 17 (0.9) | 23 (1.2) | 131 (0.8) |
| Unknown | 16 (4.1) | 59 (3.0) | 86 (4.3) | 53 (2.7) | 54 (2.8) | 57 (3.0) | 55 (2.8) | 62 (3.2) | 65 (3.3) | 507 (3.2) |
| Household income, median (IQR), $d | 54 438 (34 579-76 103) | 57 735 (34 579-76 103) | 53 255 (34 579-76 103) | 52 001 (34 579-76 103) | 57 126 (34 579-76 103) | 57 126 (34 579-76 103) | 57 735 (34 579-76 103) | 57 126 (34 579-76 103) | 57 735 (34 579-76 103) | 57 126 (34 579-76 103) |
a
Includes American Indian and other race or ethnicity.
b
Includes unknown and refused.
c
Includes no insurance and other.
d
American Community Survey (2015-2019) Median Household Income at zip code level in 2019 inflation-adjusted dollars. Data were missing for 25 participants.