3.1. General characteristics
A total of 9,405 participants (76.4%) had experience with weight control, whereas 2,906 (23.6%) had no experience. Comparing the two groups, the percentage of participants in their 40s was significantly higher among those without experience (63.8%; p<.001), and participants with a college degree or higher accounted for a high percentage of those with experience (76.0%; p<.001). The weight control group had a significantly higher percentage of employed individuals (p=.021) and those living in urban areas (p<.001). The percentages of participants living with other family members and those receiving basic livelihood support were significantly higher among those without experience (p=.006 and p<.001, respectively). The weight control group had a significantly higher average monthly income of 496.38 million won compared with 469.40 million won for those without experience (p<.001). The happiness index (life satisfaction) was significantly higher in the weight control group, with an average score of 7.24, compared with 6.96 for those without experience (p<.001). The quality of life was also significantly higher in the weight control group, with an average score of 0.94, compared with 0.93 for those without experience (p=.033). Both groups had a higher percentage of married individuals, with no significant difference between them (p=.145) (Table1).
Table 1. General characteristics (N=12,311)
Characteristics
|
Categories
|
Total
(N=12,311)
|
Experience in controlling body weight
|
p-value
|
Yes group
(n=9405, 76.4)
|
No group
(n=2906, 23.6)
|
Age
|
30’s
|
5535(45.0)
|
4482(47.7)
|
1053(36.2)
|
<.001
|
40’s
|
6776(55.0)
|
4923(52.3)
|
1853(63.8)
|
Education level
|
≤High school
|
3345(27.2)
|
2256(24.0)
|
1089(37.5)
|
<.001
|
≥College
|
8962(72.8)
|
7146(76.0)
|
1816(62.5)
|
Economic activity
|
No
|
819(6.7)
|
598(6.4)
|
221(7.6)
|
.021
|
Yes
|
11492(93.3)
|
8807(93.6)
|
2685(92.4)
|
Marital status
|
Single
|
4460(36.2)
|
3374(35.9)
|
1086(37.4)
|
.145
|
Married
|
7851(63.8)
|
6031(64.1)
|
1820(62.6)
|
Residence area
|
City
|
8359(67.9)
|
6484(68.9)
|
1875(64.5)
|
<.001
|
Province
|
3952(32.1)
|
2921(31.1)
|
1031(35.5)
|
Household type
|
Single
|
1840(14.9)
|
1452(15.4)
|
388(13.4)
|
.006
|
Other
|
10471(85.1)
|
7953(84.6)
|
2518(86.6)
|
Basic livelihood
recipients
|
No
|
12106(98.3)
|
9273(98.6)
|
2833(97.5)
|
<.001
|
Yes
|
205(1.7)
|
132(1.4)
|
73(2.5)
|
Household income
(10,000won,month)
|
490.08±281.11
|
496.38±980.47
|
469.40±682.27
|
<.001
|
Happiness
|
7.18±1.67
|
7.24±..63
|
6.96±..79
|
<.001
|
EQ-5D
|
0.93±0.05
|
0.94±0.04
|
0.93±..06
|
.033
|
3.2. Health-related characteristics
The comparison of health characteristics between the weight control experienced and non-experienced groups is shown in Table 2. The subjective health level was the highest in the weight control experienced group, with 50.1% responding as “good.” In contrast, the weight control non-experienced group showed the highest response rate of “average” at 46.2%, indicating a significant difference (p<.001). The obesity rate was significantly higher in the weight control experienced group (21.3%) than in the non-experienced group (17.3%; p<.001). The weight control experienced group had the highest rate of feeling obese, while the non-experienced group had the highest smoking rate at 65.0% (p<.001). The weight control experienced group showed the highest alcohol consumption rate at 95.0% (p=.028). The weight control experienced group had the highest frequency of drinking twice a month at 31.3%, whereas the non-experienced group had the highest frequency of drinking 2–3 times a week, showing a significant difference (p<.001). For high-risk drinking, the weight control experienced group showed a significantly higher rate of 31.2% for once a week than the non-experienced group at 29.9% (p<.001). Both groups had a higher rate of not having breakfast (p=.002), while the weight control experienced group had the highest rate of recognizing nutrition labeling at 69.8% (p<.001). The rate of not understanding nutrition labeling was high in both groups, but the weight control non-experienced group showed the highest rate at 75.4% (p<.001). Both groups had a high rate of using nutrition labeling, but the weight control experienced group had the highest rate of 82.7% (p<.001). Both groups had a high rate of consuming sufficient amounts and a variety of foods for food safety, but the weight control experienced group had the highest rate at 77.3% (p<.001).
During one week, the frequency of high-intensity physical activity was higher in the weight control group who implemented the program, with an average of 1.36 days compared with the non-implementing group’s 0.82 days (p<.001). Additionally, the high-intensity physical activity time was significantly higher in the weight control implementing group, with an average of 1.26 hours (p<.001). The frequency of moderate-intensity physical activity was also significantly higher in the weight control implementing group (average of 1.65 days) compared with the non-implementing group’s 1.28 days (p<.001). The moderate-intensity physical activity time was higher in the non-implementing group, with an average of 1.15 hours compared with the implementing group’s 1.04 hours (p<.001). The weight control implementing group also walked more days (p<.001) and for a longer period (p<.001) than the non-implementing group. Both groups had a stress level of “feeling a lot” at a rate of over 50% (p=.025), and the weight control implementing group had a higher percentage of individuals with high blood pressure at 84.3% (p<.001). The percentage of individuals who were aware of their blood pressure was higher in the weight control non-implementing group at 36.5% (p<.001), and the percentage of those who had completed blood pressure management education was higher in the weight control implementing group at 40.7% (p<.001). The percentage of individuals diagnosed with diabetes was higher in the weight control non-implementing group at 7.6% (p=.030), and the percentage of those who were aware of their blood glucose levels was higher in the weight control implementing group at 32.3% (p<.001). The percentage of those who completed diabetes management education was higher in the weight control non-implementing group (65.2%, p<.001), and the weight control implementing group had a higher percentage of individuals who utilized health care facilities (47.0%, p=.002). No significant differences were observed between the two groups in terms of smoking status (p=.069), alcohol consumption (p=.470), or depression (p=.139).
Table 2. Health-related characteristics (N=12,311)
Characteristics
|
Categories
|
Total
(N=12,311)
|
Experience in controlling body weight
|
p-value
|
Yes group
(n=9405, 76.4)
|
No group
(n=2906, 23.6)
|
Subjective health
status
|
Bad
|
851(6.9)
|
626(6.7)
|
225(7.7)
|
<.001
|
Average
|
5405(43.9)
|
4064(43.2)
|
1341(46.2)
|
Good
|
6055(49.2)
|
4715(50.1)
|
1340(46.1)
|
Body Mass Index(kg/m2)
|
Overweight
|
9803(79.6)
|
7399(78.7)
|
2404(82.7)
|
<.001
|
Obesity
|
2508(20.4)
|
2006(21.3)
|
502(17.3)
|
Body shape perception
|
Thin
|
37(0.3)
|
18(0.2)
|
19(0.7)
|
<.001
|
Average
|
1922(1.6)
|
1149(12.2)
|
773(26.6)
|
Obesity
|
10352(84.1)
|
8238(87.6)
|
2114(72.7)
|
Smoking*
|
No
|
3798(43.8)
|
3034(46.7)
|
764(35.0)
|
<.001
|
Yes
|
4880(56.2)
|
3463(53.3)
|
1417(65.0)
|
Amount of
cigarettes
|
<15
|
1923(15.6)
|
1438(15.3)
|
485(16.7)
|
.069
|
≥15
|
10388(84.4)
|
7967(84.7)
|
2421(83.3)
|
Drinking
|
No
|
650(5.3)
|
473(5.0)
|
177(6.1)
|
.028
|
Yes
|
12661(94.7)
|
8932(95.0)
|
2729(93.9)
|
Frequency of
drinking*
|
None
|
1129(9.7)
|
856(9.6)
|
273(10.0)
|
<.001
|
<1/month
|
1528(13.1)
|
1201(13.4)
|
327(12.0)
|
1/month
|
1418(12.2)
|
1069(12.0)
|
349(12.8)
|
2-4/month
|
1418(30.2)
|
2800(31.3)
|
717(26.3)
|
2-3/week
|
3093(26.5)
|
2367(26.5)
|
726(26.6)
|
≥4/week
|
976(8.4)
|
639(7.2)
|
337(12.3)
|
Amount of
drinking(7cups)*
|
1-6cups
|
4519(42.9)
|
3481(43.1)
|
1038(42.3)
|
.470
|
7-10cups
|
6013(57.1)
|
4595(56.9)
|
1418(57.7)
|
Binge drinking*
|
None
|
1879(17.8)
|
1429(17.7)
|
450(18.3)
|
<.001
|
<1/month
|
2004(19.0)
|
1569(19.4)
|
435(17.7)
|
1/month
|
2599(21.1)
|
2027(25.1)
|
572(23.3)
|
1/week
|
3251(30.9)
|
2516(31.2)
|
735(29.9)
|
Daily
|
10532(7.6)
|
535(6.6)
|
264(10.7)
|
Days of breakfast
|
None
|
5208(42.3)
|
3945(41.9)
|
1263(43.5)
|
.002
|
1-2/week
|
1399(11.4)
|
1081(11.5)
|
318(10.9)
|
3-4/week
|
1308(10.6)
|
1053(11.2)
|
255(8.8)
|
5-7/week
|
4396(35.7)
|
3326(35.4)
|
1070(36.8)
|
Awareness of
nutrition label*
|
No
|
3970(32.3)
|
2839(30.2)
|
1131(39.0)
|
<.001
|
Yes
|
8328(67.7)
|
6561(69.8)
|
1767(61.0)
|
Comprehension of nutrition label
|
No
|
5029(60.4)
|
3696(56.3)
|
1333(75.4)
|
<.001
|
Yes
|
3298(39.6)
|
2864(43.7)
|
434(24.6)
|
Use of nutrition
label*
|
No
|
611(18.5)
|
496(17.3)
|
115(26.5)
|
<.001
|
Yes
|
2686(81.5)
|
2367(82.7)
|
319(73.5)
|
Food security*
|
Sufficient quantity and variety
|
9411(76.5)
|
7274(77.3)
|
2137(73.6)
|
<.001
|
Sufficient quantity but no variety
|
2635(21.4)
|
1952(20.8)
|
683(23.5)
|
Sometimes not enough food
|
219(1.8)
|
149(1.6)
|
70(2.4)
|
Often insufficient food
|
45(0.4)
|
30(0.3)
|
15(0.5)
|
Days of strenuous physical activity(week)
|
1.23±1.90
|
1.36±..94
|
0.82±.873
|
<.001
|
Time of strenuous physical activity(hour)
|
1.19±..55
|
1.17±..54
|
1.26±..54
|
<.001
|
Days of moderate physical activity(week)
|
1.56±..16
|
1.65±..16
|
1.28±..13
|
<.001
|
Time of moderate physical activity(hour)
|
1.06±..47
|
1.04±..46
|
1.15±..13
|
<.001
|
Days of walking(week)
|
4.17±..63
|
4.36±..55
|
3.58±2.80
|
<.001
|
Time of walking(hour)
|
0.79±..36
|
0.80±.806
|
0.76±..37
|
<.001
|
Depression*
|
No
|
11948(97.2)
|
9141(97.3)
|
2807(96.8)
|
.139
|
Yes
|
348(2.8)
|
254(2.7)
|
94(3.2)
|
Stress level
|
Rare
|
582(4.7)
|
444(4.7)
|
138(4.7)
|
.025
|
Little
|
3100(25.2)
|
2408(25.6)
|
692(23.8)
|
Much
|
6892(56.0)
|
5271(56.0)
|
1621(55.8)
|
Very much
|
1737(14.1)
|
1282(13.6)
|
4555(15.7)
|
Hypertension
|
No
|
10133(82.3)
|
7682(81.7)
|
2451(84.3)
|
<.001
|
Yes
|
2718(17.7)
|
1723(18.3)
|
455(15.7)
|
Awareness of
blood pressure
level*
|
No
|
3614(29.4)
|
6836(72.8)
|
1838(63.5)
|
<.001
|
Yes
|
8674(70.6)
|
2556(27.2)
|
1058(36.5)
|
Experience of
hypertension management education
|
No
|
1341(61.6)
|
1021(59.3)
|
320(70.3)
|
<.001
|
Yes
|
836(38.4)
|
701(40.7)
|
135(29.7)
|
Diabetes
|
No
|
11485(93.3)
|
8880(93.6)
|
2685(92.4)
|
.030
|
Yes
|
286(6.7)
|
605(6.4)
|
221(7.6)
|
Awareness of
blood sugar level
|
No
|
8481(69.2)
|
6338(67.7)
|
2143(74.3)
|
<.001
|
Yes
|
3772(30.8)
|
3030(32.3)
|
742(25.7)
|
Experience of
diabetes management education
|
No
|
395(47.8)
|
318(52.6)
|
77(34.8)
|
<.001
|
Yes
|
431(52.2)
|
287(47.4)
|
144(65.2)
|
Use of health institutions
|
No
|
6617(53.8)
|
4983(53.0)
|
1634(56.2)
|
.002
|
*missing data
3.3. Prediction model for weight control experience
The prediction model for weight control experience in the target group is presented in Figure 1. Subjective body shape perception significantly impacted weight control experience (△p<.001, F=365.67). In cases where individuals perceived themselves as obese (Node 1), 79.6% had experienced weight control, with differences in weight control experience observed based on education level (△p<.001, F=123.43). The weight control attempt rate was 82.2% for those with a college degree or higher (Node 3) and 72.1% for those with a high school degree or lower. For individuals with a college degree or higher, there was a significant difference in weight control experience based on smoking status (△p<.001, F=63.27), with 84.6% of non-smokers having tried weight control compared with 77.3% of smokers. For those with a high school degree or lower (Node 4), completing high blood pressure management education had a significant impact on weight control experience (△p<.001, F=18.272). The weight control attempt rate was 84.5% for those who completed high blood pressure management education and 75.5% for those who did not.
Individuals who perceived themselves to be average or below average in terms of subjective body shape perception (Node 2) had different experiences with weight control depending on their education level (Δp<.001, F=46.31). Among those with a college degree or higher, 65.1% had experienced weight control, whereas among those with a high school diploma or lower, only 49.3% had experienced weight control. Among those with a college degree or higher, there were differences in weight control experiences by age (Δp<.001, F=24.43), with 59.3% of those in their 40s and 72.6% of those in their 30s having experienced weight control. Among those with a high school diploma or less (Node 6), there were differences in weight control experiences depending on whether they were aware of their blood glucose levels (Δp<.001, F=17.83). Among those unaware of their blood glucose levels (Node 14), 44.7% had experienced weight control, whereas among those who were aware of their blood glucose levels (Node 15), 63.5% had done so.
Individuals who perceived themselves as obese, with a college degree or higher, and did not smoke had the highest rate of weight control (84.6%). On the contrary, individuals who perceived themselves as having an average or below-average weight, had a high school education or lower, and were unaware of their blood glucose levels had the highest rate of not controlling their weight at 55.3%.
3.4. Prediction model for weight control experience by age
The analysis of whether the participants had experience controlling their weight was categorized based on age, and the results are shown in Figure 2. Age was found to be a significant factor affecting weight control experience (△p<.001, F=117.00), where 72.7% of those in their 40s (Node 1) and 81.0% in their 30s (Node 2) had experienced weight control. For those in their 40s, there were differences in weight control experience because of their physical condition (△p<.001, F=262.60). Among those who considered themselves obese (Node 3), 76.8% had experienced weight control, whereas 54.1% of those who considered themselves average or below had experienced weight control. Among those aware of their blood pressure (Node 7), 79.2% had experienced weight control. In contrast, among those who were unaware of their blood pressure (Node 8), 68.6% had experienced weight control; this difference was statistically significant (△p<.001, F=18.272). Among those whose physical condition was average or below (Node 4), there were differences in weight control experience depending on whether they were aware of their blood glucose levels (△p<.001, F=19.480). Among those unaware of their blood glucose levels (Node 9), 49.9% had experienced weight control, whereas among those who were aware of their blood glucose levels (Node 10), 63.3% had experienced weight control.
It was found that men in their 30s had different experiences with weight control owing to their physical condition (Δp<0.001, F=77.126). Among those who considered themselves obese (Node 5), 82.8% had experienced weight control, whereas among those who considered themselves to have average or below weight (Node 6), 69.0% had experienced weight control. Regarding those who considered themselves obese, education level had an impact on weight control experiences (Δp<0.001, F=46.98). Those with a college degree or higher (Node 11) had an 84.6% rate of weight control attempts, whereas those who graduated from high school or below had a 75.2% rate. Similarly, among those who considered themselves average or below, education level also impacted weight control experiences (Δp<0.001, F=14.97). Those with a college degree or higher (Node 13) had a 72.6% rate of weight control attempts, whereas those who had graduated from high school or below had a 56.7% rate. The study found that, among those in their 30s who considered themselves obese and had a college degree or higher, the attempt rate for weight control was the highest at 84.6%. Conversely, among those in their 40s who considered themselves average or below weight and were unaware of their blood glucose levels, the rate of not attempting weight control was the highest at 50.1%.
3.5. Prediction model for weight control experience by BMI
We categorized the participants based on their experience with weight management using BMI as the first criterion, and the results are shown in Figure 3. BMI significantly impacted weight management experience (△p<.001, F=46.98). Among those who were overweight, 75.5% attempted to manage their weight, compared with 80.0% of those who were obese. For those who were overweight (Node 1), there was a difference in weight management experience based on physical condition (△p<.001, F=320.46). Among those who perceived themselves as obese (Node 3), 79.3% had attempted weight management if they thought they were average or below. A difference was observed in weight management experience based on education level for those who perceived themselves as obese (Node 3) (△p<.001, F=105.39). Those with a college degree or higher (Node 7) and those with a high school diploma or less (Node 8) had 82.0% and 71.2% weight management experience, respectively. For those who perceived themselves as having an average or below average physical condition (Node 4), there was also a difference in weight management experience based on education level (△p<.001, F=49.07). Those with a college degree or higher (Node 9) and those with a high school diploma or less (Node 10) had 65.2% and 48.5% weight management experience, respectively.
Differences were observed in weight control experiences based on the education level of individuals with obesity (Node 2) (△p<.001, F=23.61). A total of 82.5% of those who had graduated from university or higher (Node 5) and 73.9% of those who had graduated from high school or lower (Node 6) had experience with weight control. Among those who graduated from university or higher (Node 5), there were differences in weight control experiences based on smoking status. Of those who did not currently smoke (Node 11), 84.9% had experienced weight control, whereas 78.0% of those who smoked had experienced weight control. The rate of weight control experiences was highest for those who were obese, graduated from a university or higher, and did not currently smoke, with a rate of 84.9%. On the contrary, the rate of not controlling weight was highest for those who were overweight, perceived themselves as having an average or lower weight, and graduated from high school or lower, with a rate of 51.5%.
3.6. Validation of prediction models
The validity of the predictive model derived in this study is shown in Table 3. The risk estimate of the training data for the predictive model derived from all participants was .227, indicating a 77.3% probability of the predictive model being classified properly. The accuracy of the predictive models derived by setting age and BMI as the first separators were 76.9% and 76.7%, respectively, indicating a high probability of all three models being properly classified.
Table 3. Validation of prediction model
Model
|
Sample
|
Risk Estimate(RE)
|
Standard Error
|
Total
|
Training
|
.227
|
.005
|
Test
|
.239
|
.005
|
Age
|
Training
|
.231
|
.005
|
Test
|
.230
|
.005
|
Body Mass Index
|
Training
|
.233
|
.005
|
Test
|
.239
|
.005
|