Table 1 Weighted Sample Characteristics among Oldest-old, 1998–2018

Informal Caregivers

19,436 (95.0)

7,724 (90.6)

11,712 (97.2)

 < .001

Place of death

 < .001

 Home

18,285 (87.5)

6,820 (75.8)

11,465 (93.2)

 Hospital

1,389 (8.9)

1,086 (17.2)

303 (4.8)

 Nursing home facilities

475 (3.6)

329 (7.0)

146 (2.0)

Age at death

97 (91,102)

96 (91,102)

97 (92,102)

 < .001

 80–89

3,757 (77.8)

1,666 (75.7)

2,091 (78.9)

0.001

 90–99

8,216 (21.4)

3,420 (23.2)

4,796 (20.4)

 ≥ 100

8,176 (0.8)

3,149 (1.1)

5,027 (0.7)

Gender

0.59

 Female

12,490 (58.6)

4,956 (58.0)

7,534 (59.0)

Ethnicity

0.01

 Han

18,752 (92.4)

7,777 (93.9)

10,975 (91.6)

Being married during the last year of life

2,418 (20.4)

1,106 (24.1)

1,312 (18.6)

 < .001

Years of schooling

 < .001

 0

14,738 (67.5)

5,496 (59.6)

9,242 (71.3)

 1–6

4,488 (27.2)

2,158 (31.0)

2,330 (25.4)

 ≥ 7

923 (5.3)

581 (9.4)

342 (3.3)

Number of children

0.003

 0–2

4,145 (20.4)

1,887 (24.1)

2,258 (18.6)

 3–4

5,849 (29.0)

2,303 (27.0)

3,546 (29.9)

 5–6

5,792 (29.0)

2,293 (27.8)

3,499 (29.6)

 ≥ 7

4,363 (21.6)

1,752 (21.1)

2,611 (21.9)

Per capita household income annually

 < .001

 < 391

4,985 (35.4)

1,551 (25.6)

3,434 (40.1)

 391–942

5,159 (30.5)

1,950 (28.8)

3,209 (31.2)

 942–3,060

4,995 (20.1)

2,170 (24.8)

2,825 (17.9)

 > 3,060

5,010 (14.0)

2,564 (20.8)

2,446 (10.8)

Main financial source

 Retirement wage

1,977 (11.2)

1,626 (25.7)

351 (4.1)

 < .001

 Family

16,845 (82.4)

5,965 (65.0)

10,880 (91.0)

 < .001

 White-collar jobs before retirement

816 (4.7)

596 (9.5)

220 (2.4)

 < .001

Living arrangement

 living alone

2,007 (11.3)

735 (10.3)

1,272 (11.8)

0.16

 living in the nursing home

486 (4.5)

344 (8.4)

142 (2.5)

 < .001

 living with spouse only

1,940 (12.6)

861 (15.5)

1,079 (11.2)

 < .001

 living with other family members

15,373 (70.3)

6,117 (64.2)

9,256 (73.3)

 < .001

timely medical services

0.01

 Yes

15,014 (81.6)

6,310 (83.8)

8,704 (80.5)

 No

1,322 (8.2)

572 (8.1)

750 (8.2)

 Was not ill

3,760 (10.2)

1,334 (8.1)

2,426 (11.3)

Health Condition

 Self-rated health status

0.43

  Very good or good

7,415 (41.2)

3,105 (40.3)

4,310 (41.6)

  So so

6,127 (32.4)

2,561 (34.2)

3,566 (31.6)

  Bad or very bad

3,152 (19.7)

1,215 (18.9)

1,937 (20.2)

  Not able to answer

3,455 (6.7)

1,354 (6.6)

2,101 (6.8)

 Any disability in ADLs

3,581 (25.6)

1,316 (21.7)

2,265 (27.5)

 < .001

 Bedridden before dying

14,947 (27.1)

6,143 (25.8)

8,804 (27.8)

0.23

 No of comorbidities

 < .001

  0

7,248 (33.1)

2,502 (27.7)

4,746 (35.6)

  1

6,466 (32.9)

2,538 (31.8)

3,928 (33.5)

  2

2,921 (15.1)

1,307 (16.7)

1,614 (14.4)

  ≥ 3

3,514 (18.9)

1,888 (23.8)

1,626 (16.5)

Health Behavior^a

 Physical exercise

3,920 (24.6)

2,011 (31.4)

1,909 (21.3)

 < .001

 Smoking

2,832 (18.6)

1,065 (15.9)

1,767 (20.0)

0.003

 Drinking

3,233 (15.9)

1,242 (14.4)

1,991 (16.7)

0.07

 Region

 < .001

  Eastern

7,714 (35.6)

3,347 (36.1)

4,367 (35.4)

  Central

4,688 (24.5)

1,430 (18.0)

3,258 (27.7)

  Western

6,161 (31.4)

2,471 (32.2)

3,690 (31.0)

  Northeast

1,586 (8.5)

987 (13.7)

599 (5.9)