, Eun-hee Jang2)
, Seungmin Lee3),†
1)Master student, Department of Food and Nutrition, Sungshin Women’s University, Seoul, Korea
2)Doctoral student, Department of Food and Nutrition, Sungshin Women’s University, Seoul, Korea
3)Professor, Department of Food and Nutrition, Sungshin Women’s University, Seoul, Korea
© 2023 The Korean Society of Community Nutrition
This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Conflict of Interest
There are no financial or other issues that might lead to a conflict of interest.
Funding
This study was supported by the Korean Society of Community Nutrition funded by the Korea Disease Control and Prevention Agency (No. ISSN 2733-5488).
Acknowledgments
The author wishes to thank the Korean Society of Community Nutrition for providing the opportunity to participate in the 2022 Excellent Researcher Research Support Project.
Data Availability
The data that support the findings of this study are openly available in the Consumer Behavior Survey for Foods at https://www.krei.re.kr/foodSurvey/index.do, and are available at request in the Korea Community Health Survey at https://chs.kdca.go.kr/
| Variables |
Seoul metropolitan area |
P-value | ||
|---|---|---|---|---|
| 2018 (n = 2,011) | 2019 (n = 1,801) | 2020 (n = 1,936) | ||
| Eating-out1) | n = 2,011 | n = 1,801 | n = 1,936 | < 0.001 |
| Yes | 1,851 (92.5)a | 1,675 (94.1)a | 1,635 (85.3)b | |
| Frequency of eating out | n = 1,851 | n = 1,675 | n = 1,635 | 0.088 |
| ≥ 1 time/week | 1,166 (66.8) | 1,130 (71.1) | 1,072 (70.4) | |
| 1 time/2 weeks | 375 (18.5) | 275 (16.4) | 297 (15.9) | |
| ≤ 1 time/month | 310 (14.6) | 270 (12.5) | 266 (13.8) | |
| Eating-out expenditure (thousand won/month)2)3) | 110,862.6 ± 1,853.3a | 119,238.9 ± 1,779.4b | 121,962.9 ± 1,874.3b | < 0.001 |
| Eating-out with family1) | n = 2,011 | n = 1,801 | n = 1,936 | < 0.001 |
| Yes | 1,729 (87.4)a | 1,625 (92.3)b | 1,628 (83.7)a | |
| Frequency of eating out with family1) | n = 1,729 | n = 1,625 | n = 1,628 | 0.024 |
| ≥ 1 time/week | 483 (32.0)a | 558 (25.2)ab | 628 (41.5)b | |
| 1 time/2 weeks | 673 (36.9) | 558 (36.7) | 575 (32.2) | |
| ≤ 1 time/month | 573 (31.1) | 509 (38.1) | 425 (26.3) | |
| Eating-out expenditure with family (thousand won/month)2)3) | 124,559.7 ± 1,767.4a | 124,599.0 ± 1,662.4a | 130,443.8 ± 1,750.4b | < 0.001 |
| Variables |
Metropolitan cities |
P-value | ||
|---|---|---|---|---|
| 2018 (n = 1,805) | 2019 (n = 1,762) | 2020 (n = 1,727) | ||
| Eating-out | n = 1,805 | n = 1,762 | n = 1,727 | 0.092 |
| Yes | 1,691 (94.1) | 1,650 (92.7) | 1,576 (90.4) | |
| Frequency of eating out | n = 1,691 | n = 1,650 | n = 1,576 | 0.080 |
| ≥ 1 time/week | 964 (56.7) | 950 (59.3) | 943 (61.6) | |
| 1 time/2 weeks | 305 (17.3) | 288 (16.8) | 298 (18.6) | |
| ≤ 1 time/month | 422 (26.1) | 412 (23.8) | 335 (19.8) | |
| Eating-out expenditure (thousand won/month)2)3) | 96,369.1 ± 2,042.5a | 107,740.7 ± 2,028.0b | 108,115.5 ± 1,977.3b | < 0.001 |
| Eating-out with family | n = 1,805 | n = 1,762 | n = 1,727 | 0.174 |
| Yes | 1,613 (89.8) | 1,594 (91.2) | 1,510 (87.2) | |
| Frequency of eating out with family | n = 1,613 | n = 1,594 | n = 1,510 | 0.069 |
| ≥ 1 time/week | 610 (41.3) | 481 (31.7) | 500 (33.5) | |
| 1 time/2 weeks | 466 (26.0) | 480 (31.2) | 405 (27.2) | |
| ≤ 1 time/month | 537 (32.6) | 633 (37.1) | 605 (39.3) | |
| Eating-out expenditure with family (thousand won/month)2)3) | 108,300.4 ± 2,059.9 | 111,910.0 ± 2,016.2a | 107,146.6 ± 1,983.1a | 0.475 |
| Variables |
Provinces |
P-value | ||
|---|---|---|---|---|
| 2018 (n = 2,762) | 2019 (n = 2,613) | 2020 (n = 2,692) | ||
| Eating-out1) | n = 2,762 | n = 2,613 | n = 2,692 | < 0.001 |
| Yes | 2,274 (84.3)a | 2,212 (87.3)a | 2,174 (78.4)b | |
| Frequency of eating-out | n = 2,274 | n = 2,212 | n = 2,174 | 0.111 |
| ≥ 1 time/week | 1,024 (47.7) | 1,029 (49.0) | 972 (44.0) | |
| 1 time/2 weeks | 536 (22.0) | 458 (19.2) | 446 (21.6) | |
| ≤ 1 time/month | 714 (30.3) | 725 (31.8) | 756 (34.4) | |
| Eating-out expenditure (thousand won/month)2)3) | 88,540.9 ± 1,566.9 | 89,531.5 ± 1,497.3 | 89,273.0 ± 1,540.2 | 0.514 |
| Eating-out with family1) | n = 2,762 | n = 2,613 | n = 2,692 | 0.004 |
| Yes | 2,065 (76.6)a | 2,091 (82.3)b | 2,081 (75.9)a | |
| Frequency of eating-out with family | n = 2,065 | n = 2,091 | n = 2,081 | 0.274 |
| ≥ 1 time/week | 711 (36.1) | 615 (31.4) | 601 (29.9) | |
| 1 time/2 weeks | 549 (26.3) | 597 (28.2) | 619 (31.3) | |
| ≤ 1 time/month | 805 (37.6) | 879 (40.4) | 861 (38.8) | |
| Eating-out expenditure with family (thousand won/month)2)3) | 94,543.3 ± 1,722.0a | 101,290.0 ± 1,613.9b | 107,515.3 ± 1,636.1c | < 0.001 |
Mean ± SE or n (%)
P-values by chi-square or ANOVA test
1)Chi-square tests compared categorical variables across survey years (2018-2019, 2019-2020, 2018-2020); significant differences (P = 0.05) are indicated by different lowercase letters in the same row.
2)Bonferroni tests compared continuous variables across 2018-2020 survey years; significant differences (P < 0.05) are indicated by different lowercase letters in the same row.
3)Adjusted for age, sex, education level, and household income
| Variables |
Seoul metropolitan area |
P-value | ||
|---|---|---|---|---|
| 2018 (n = 2,011) | 2019 (n = 1,801) | 2020 (n = 1,936) | ||
| Using deliveries/takeout | n = 2,011 | n = 1,801 | n = 1,936 | 0.051 |
| Yes | 1,297 (64.3) | 1,058 (60.3) | 1,020 (56.6) | |
| Frequency of deliveries/take-outs1) | n = 1,297 | n = 1,058 | n = 1,020 | < 0.001 |
| ≥ 1 time/week | 372 (30.5)a | 382 (40.0)b | 436 (44.4)b | |
| 1 time/2 weeks | 482 (36.1) | 393 (35.1) | 342 (34.1) | |
| ≤ 1 time/month | 443 (33.4) | 283 (24.9) | 242 (21.5) | |
| Deliveries/takeout food expenditure (thousand won/month)3) | - | 55,695.6 ± 13,273.1 | 57,983.2 ± 9,475.6 | < 0.001 |
| Using deliveries or takeout with family | n = 2,011 | n = 1,801 | n = 1,936 | 0.565 |
| Yes | 1,619 (81.6) | 1,421 (82.0) | 1,543 (79.5) | |
| Frequency of deliveries/takeout with family1) | n = 1,619 | n = 1,421 | n = 1,543 | < 0.001 |
| ≥ 1 time/week | 442 (31.4)a | 418 (31.6)a | 639 (44.1)b | |
| 1 time/2 weeks | 567 (33.6) | 572 (42.2) | 617 (39.4) | |
| ≤ 1 time/month | 610 (35.0) | 431 (26.3) | 287 (16.5) | |
| Deliveries/takeout food expenditure with family (thousand won/month)2)3) | 55,815.5 ± 1,042.6a | 54,407.5 ± 1,010.7a | 61,191.2 ± 1,025.7b | < 0.001 |
| Variables |
Metropolitan cities |
P-value | ||
|---|---|---|---|---|
| 2018 (n = 1,805) | 2019 (n = 1,762) | 2020 (n = 1,727) | ||
| Using deliveries/takeout | n = 1,805 | n = 1,762 | n = 1,727 | 0.310 |
| Yes | 798 (45.5) | 862 (50.4) | 808 (46.2) | |
| Frequency of deliveries/take-outs | n = 798 | n = 862 | n = 808 | 0.391 |
| ≥ 1 time/week | 258 (34.5) | 248 (30.5) | 247 (32.3) | |
| 1 time/2 weeks | 251 (30.8) | 270 (32.0) | 281 (36.0) | |
| ≤ 1 time/month | 289 (34.7) | 344 (37.6) | 280 (31.7) | |
| Deliveries/takeout food expenditure (thousand won/month)3) | - | 50,805.2 ± 15,047.7 | 46,188.7 ± 11,729.8 | 0.053 |
| Using deliveries or takeout with family | n = 1,805 | n = 1,762 | n = 1,727 | 0.080 |
| Yes | 1,390 (78.9) | 1,281 (73.9) | 1,297 (74.5) | |
| Frequency of deliveries/takeout with family | n = 1,390 | n = 1,281 | n = 1,297 | 0.263 |
| ≥ 1 time/week | 425 (34.6) | 402 (33.9) | 434 (33.7) | |
| 1 time/2 weeks | 475 (35.8) | 381 (28.6) | 361 (26.3) | |
| ≤ 1 time/month | 490 (29.6) | 498 (37.5) | 502 (5.00) | |
| Deliveries/takeout food expenditure with family (thousand won/month)3) | 49,346.4 ± 1,040.5 | 53,954.2 ± 1,059.0 | 46,603.0 ± 1,017.2 | 0.232 |
| Variables |
Provinces |
P-value | ||
|---|---|---|---|---|
| 2018 (n = 2,762) | 2019 (n = 2,613) | 2020 (n = 2,692) | ||
| Using deliveries/takeout1) | n = 2,762 | n = 2,613 | n = 2,692 | < 0.001 |
| Yes | 1,120 (44.1)a | 951 (40.1)ab | 939 (35.0)b | |
| Frequency of deliveries/take-outs | n = 1,120 | n = 951 | n = 939 | 0.178 |
| ≥ 1 time/week | 313 (32.6) | 266 (30.5) | 232 (25.3) | |
| 1 time/2 weeks | 318 (26.5) | 209 (21.6) | 283 (29.8) | |
| ≤ 1 time/month | 489 (40.9) | 476 (48.0) | 424 (44.8) | |
| Deliveries/takeout food expenditure (thousand won/month)3) | - | 36,884.8 ± 13,725.2 | 39,227.2 ± 10,660.1 | 0.001 |
| Using deliveries or takeout with family | n = 2,762 | n = 2,613 | n = 2,692 | 0.063 |
| Yes | 1,758 (67.9) | 1,600 (64.0) | 1,717 (62.3) | |
| Frequency of deliveries/takeout with family | n = 1,758 | n = 1,600 | n = 1,717 | 0.444 |
| ≥ 1 time/week | 452 (28.6) | 396 (28.0) | 498 (29.0) | |
| 1 time/2 weeks | 558 (33.5) | 498 (32.3) | 598 (37.5) | |
| ≤ 1 time/month | 748 (37.8) | 706 (39.5) | 621 (33.5) | |
| Deliveries/takeout food expenditure with family (thousand won/month)2)3) | 47,929.1 ± 1,008.6a | 52,152.6 ± 51,007.1b | 56,267.8 ± 10,994.7c | < 0.001 |
Mean ± SE or n (%)
P-values by chi-square or ANOVA test
1)Chi-square tests compared categorical variables across survey years (2018-2019, 2019-2020, 2018-2020); significant differences (P < 0.05) are indicated by different lowercase letters in the same row.
2)Bonferroni tests compared continuous variables across 2018-2020 survey years; significant differences (P < 0.05) are indicated by different lowercase letters in the same row.
3)Adjusted for age, sex, education level, and household income
| Variables | 2018 (n = 228,340) | 2019 (n = 229,099) | 2020 (n = 229,269) | P-value1)2) |
|---|---|---|---|---|
| Frequency of breakfast (times/week) | ||||
| Seoul metropolitan area (n = 220,486) | 5.01 ± 0.01Aa | 3.89 ± 0.01Ab | 3.76 ± 0.01Ac | < 0.001 |
| Metropolitan cities (n = 109,331) | 5.23 ± 0.01Ba | 4.12 ± 0.01Bb | 3.96 ± 0.01Bc | < 0.001 |
| Provinces (n = 356,828) | 5.60 ± 0.01Ca | 4.54 ± 0.01Cb | 4.44 ± 0.01Cc | < 0.001 |
| P-value2)3) | < 0.001 | < 0.001 | < 0.001 | |
| Use of nutrition labels when purchasing processed foods (yes) | ||||
| Seoul metropolitan area (n = 220,486) | 14,655 (21.9)a | 17,088 (25.1)b | 17,761 (25.6)b | < 0.001 |
| Metropolitan cities (n = 109,331) | 7,076 (21.3)a | 8,053 (23.7)b | 8,284 (24.3)b | < 0.001 |
| Provinces (n = 356,828) | 14,716 (16.4)a | 18,461 (20.2)b | 19,251 (20.5)b | < 0.001 |
| P-value4) | < 0.001 | < 0.001 | < 0.001 | |
Mean ± SE or n (%)
P-values by chi-square or ANOVA test
1)Bonferroni tests compared continuous variables across 2018-2020 survey years; significant differences (P < 0.05) are indicated by different lowercase letters in the same row.
2)Adjusted for age, sex, education level, and household income
3)Bonferroni tests compared continuous variables across regions (Seoul metropolitan area, Metropolitan cities, Provinces); significant differences (P < 0.05) are indicated by different uppercase letters in the same column.
4)Chi-square tests compared categorical variables across survey years (2018-2019, 2019-2020, 2018-2020); significant differences (P < 0.05) are indicated by different lowercase letters in the same row.
| Variable | Seoul metropolitan area (n = 220,497) | Metropolitan cities (n = 109,333) | Provinces (n = 356,878) | P-value |
|---|---|---|---|---|
| Age (years) | 47.2 ± 0.1 | 48.3 ± 0.1 | 50.5 ± 0.1 | < 0.001 |
| Sex | ||||
| Men | 99,890 (49.4) | 49,205 (49.3) | 159,612 (50.1) | < 0.001 |
| Women | 120,607 (50.6) | 60,128 (50.7) | 197,266 (49.9) | |
| Education level | ||||
| ≤Middleschool | 49,999 (16.0) | 29,457 (21.0) | 167,280 (28.0) | < 0.001 |
| High school | 81,551 (37.5) | 38,581 (36.5) | 108,182 (37.5) | |
| College & university | 78,564 (40.8) | 37,693 (39.2) | 74,510 (31.5) | |
| Graduate school | 9,882 (5.2) | 3,528 (3.8) | 6,559 (2.7) | |
| Household income (10,000 won/month) | ||||
| ≤ 200 | 42,039 (15.4) | 28,047 (20.6) | 145,109 (27.0) | < 0.001 |
| 200-499 | 89,040 (41.2) | 47,643 (45.4) | 135,851 (43.4) | |
| ≥ 500 | 83,977 (43.5) | 32,525 (34.1) | 70,095 (29.6) | |
| High-risk alcohol consumption | 25,066 (14.2) | 11,856 (13.7) | 36,677 (15.3) | < 0.001 |
| Smoking | ||||
| None | 142,327 (62.6) | 70,686 (62.8) | 227,869 (60.8) | < 0.001 |
| Ex-smoker | 38,147 (17.5) | 19,241 (17.6) | 69,821 (18.8) | |
| Current smoker | 39,992 (19.9) | 19,400 (19.6) | 59,168 (20.4) | |
| Frequency of breakfast (times/week) | 4.2 ± 0.0 | 4.4 ± 0.0 | 4.5 ± 4.5 | < 0.001 |
| Use of nutrition label | 49,504 (24.2) | 23,413 (23.1) | 52,428 (19.0) | < 0.001 |
| Obesity (BMI ≥ 25 kg/m2) | 71,208 (32.6) | 33,866 (31.4) | 118,882 (34.5) | < 0.001 |
| Hypertension | 52,993 (19.9) | 25,022 (19.2) | 116,876 (23.2) | < 0.001 |
| Diabetes mellitus | 21,722 (8.1) | 10,946 (8.3) | 46,069 (9.5) | < 0.001 |
| High-risk subjective stress level | 57,183 (27.3) | 24,687 (23.5) | 72,888 (23.6) | < 0.001 |
| Major Depressive disorder | 7,763 (3.4) | 3,316 (2.7) | 11,482 (3.2) | < 0.001 |
| Sleep duration (hours/day) | 6.7 ± 0.0 | 6.7 ± 0.0 | 6.8 ± 0.0 | < 0.001 |
| Variables | Seoul metropolitan area (n = 5,748) | Metropolitan cities (n = 5,294) | Provinces (n = 8,067) | P-value |
|---|---|---|---|---|
| Age (years) | 45.4 ± 0.5 | 45.0 ± 0.5 | 48.2 ± 0.6 | < 0.001 |
| Sex | 0.017 | |||
| Men | 2,637 (50.2) | 2,421 (51.8) | 3,516 (48.2) | |
| Women | 3,111 (49.8) | 2,873 (48.2) | 4,551 (51.8) | |
| Education level | < 0.001 | |||
| ≤Middleschool | 414 (7.4) | 606 (11.9) | 1,778 (22.1) | |
| High school | 2,640 (41.4) | 2,588 (44.9) | 3,456 (39.5) | |
| College & university | 2,666 (50.6) | 2,051 (42.4) | 2,783 (37.6) | |
| Graduate school | 28 (0.6) | 49 (0.8) | 50 (0.8) | |
| Household income (10,000 won/month) | < 0.001 | |||
| ≤ 200 | 102 (1.8) | 226 (4.5) | 606 (7.9) | |
| 200-499 | 3,134 (51.2) | 3,437 (63.6) | 5,611 (68.4) | |
| ≥ 500 | 2,512 (47.0) | 1,631 (31.9) | 1,850 (23.6) |
| Variables | Seoul metropolitan area |
P-value | ||
|---|---|---|---|---|
| 2018 (n = 2,011) | 2019 (n = 1,801) | 2020 (n = 1,936) | ||
| Eating-out |
n = 2,011 | n = 1,801 | n = 1,936 | < 0.001 |
| Yes | 1,851 (92.5)a | 1,675 (94.1)a | 1,635 (85.3)b | |
| Frequency of eating out | n = 1,851 | n = 1,675 | n = 1,635 | 0.088 |
| ≥ 1 time/week | 1,166 (66.8) | 1,130 (71.1) | 1,072 (70.4) | |
| 1 time/2 weeks | 375 (18.5) | 275 (16.4) | 297 (15.9) | |
| ≤ 1 time/month | 310 (14.6) | 270 (12.5) | 266 (13.8) | |
| Eating-out expenditure (thousand won/month) |
110,862.6 ± 1,853.3a | 119,238.9 ± 1,779.4b | 121,962.9 ± 1,874.3b | < 0.001 |
| Eating-out with family |
n = 2,011 | n = 1,801 | n = 1,936 | < 0.001 |
| Yes | 1,729 (87.4)a | 1,625 (92.3)b | 1,628 (83.7)a | |
| Frequency of eating out with family |
n = 1,729 | n = 1,625 | n = 1,628 | 0.024 |
| ≥ 1 time/week | 483 (32.0)a | 558 (25.2)ab | 628 (41.5)b | |
| 1 time/2 weeks | 673 (36.9) | 558 (36.7) | 575 (32.2) | |
| ≤ 1 time/month | 573 (31.1) | 509 (38.1) | 425 (26.3) | |
| Eating-out expenditure with family (thousand won/month) |
124,559.7 ± 1,767.4a | 124,599.0 ± 1,662.4a | 130,443.8 ± 1,750.4b | < 0.001 |
| Variables | Seoul metropolitan area |
P-value | ||
|---|---|---|---|---|
| 2018 (n = 2,011) | 2019 (n = 1,801) | 2020 (n = 1,936) | ||
| Using deliveries/takeout | n = 2,011 | n = 1,801 | n = 1,936 | 0.051 |
| Yes | 1,297 (64.3) | 1,058 (60.3) | 1,020 (56.6) | |
| Frequency of deliveries/take-outs |
n = 1,297 | n = 1,058 | n = 1,020 | < 0.001 |
| ≥ 1 time/week | 372 (30.5)a | 382 (40.0)b | 436 (44.4)b | |
| 1 time/2 weeks | 482 (36.1) | 393 (35.1) | 342 (34.1) | |
| ≤ 1 time/month | 443 (33.4) | 283 (24.9) | 242 (21.5) | |
| Deliveries/takeout food expenditure (thousand won/month) |
- | 55,695.6 ± 13,273.1 | 57,983.2 ± 9,475.6 | < 0.001 |
| Using deliveries or takeout with family | n = 2,011 | n = 1,801 | n = 1,936 | 0.565 |
| Yes | 1,619 (81.6) | 1,421 (82.0) | 1,543 (79.5) | |
| Frequency of deliveries/takeout with family |
n = 1,619 | n = 1,421 | n = 1,543 | < 0.001 |
| ≥ 1 time/week | 442 (31.4)a | 418 (31.6)a | 639 (44.1)b | |
| 1 time/2 weeks | 567 (33.6) | 572 (42.2) | 617 (39.4) | |
| ≤ 1 time/month | 610 (35.0) | 431 (26.3) | 287 (16.5) | |
| Deliveries/takeout food expenditure with family (thousand won/month) |
55,815.5 ± 1,042.6a | 54,407.5 ± 1,010.7a | 61,191.2 ± 1,025.7b | < 0.001 |
| Variables | 2018 (n = 228,340) | 2019 (n = 229,099) | 2020 (n = 229,269) | P-value |
|---|---|---|---|---|
| Frequency of breakfast (times/week) | ||||
| Seoul metropolitan area (n = 220,486) | 5.01 ± 0.01Aa | 3.89 ± 0.01Ab | 3.76 ± 0.01Ac | < 0.001 |
| Metropolitan cities (n = 109,331) | 5.23 ± 0.01Ba | 4.12 ± 0.01Bb | 3.96 ± 0.01Bc | < 0.001 |
| Provinces (n = 356,828) | 5.60 ± 0.01Ca | 4.54 ± 0.01Cb | 4.44 ± 0.01Cc | < 0.001 |
| P-value |
< 0.001 | < 0.001 | < 0.001 | |
| Use of nutrition labels when purchasing processed foods (yes) | ||||
| Seoul metropolitan area (n = 220,486) | 14,655 (21.9)a | 17,088 (25.1)b | 17,761 (25.6)b | < 0.001 |
| Metropolitan cities (n = 109,331) | 7,076 (21.3)a | 8,053 (23.7)b | 8,284 (24.3)b | < 0.001 |
| Provinces (n = 356,828) | 14,716 (16.4)a | 18,461 (20.2)b | 19,251 (20.5)b | < 0.001 |
| P-value |
< 0.001 | < 0.001 | < 0.001 | |
Mean ± SE or n (%)
Mean ± SE or n (%)
Mean ± SE or n (%) Chi-square tests compared categorical variables across survey years (2018-2019, 2019-2020, 2018-2020); significant differences ( Bonferroni tests compared continuous variables across 2018-2020 survey years; significant differences ( Adjusted for age, sex, education level, and household income
Mean ± SE or n (%) Chi-square tests compared categorical variables across survey years (2018-2019, 2019-2020, 2018-2020); significant differences ( Bonferroni tests compared continuous variables across 2018-2020 survey years; significant differences ( Adjusted for age, sex, education level, and household income
Mean ± SE or n (%) Bonferroni tests compared continuous variables across 2018-2020 survey years; significant differences ( Adjusted for age, sex, education level, and household income Bonferroni tests compared continuous variables across regions (Seoul metropolitan area, Metropolitan cities, Provinces); significant differences ( Chi-square tests compared categorical variables across survey years (2018-2019, 2019-2020, 2018-2020); significant differences (
