Table 3.
Comparison of questionnaire among underweight and normal-weight Women (t-test/chi-square test).
| Underweight n = 400 | Normal range n = 189 | t | p | |||
|---|---|---|---|---|---|---|
| Mean | SD | Mean | SD | |||
| (a) Demographic Data | ||||||
| Age (years) | 25.03 | 3.04 | 25.49 | 3.04 | −1.723 | 0.085 |
| Age at first menstruation (years) | 12.67 | 1.58 | 12.39 | 1.43 | 2.038 | 0.042 |
| Height (cm) | 158.73 | 5.96 | 158.27 | 5.15 | 0.961 | 0.337 |
| Weight (kg) | 43.96 | 3.99 | 51.78 | 5.10 | −18.572 | <0.001 |
| BMI (Kg/m2) | 17.43 | 0.92 | 20.65 | 1.55 | −26.474 | <0.001 |
| Birth weight (g)‡ (n = 304/189) | 2982.58 | 372.77 | 3030.47 | 413.78 | −1.329 | 0.092 |
| Maximum weight (kg)[BMI] | 49.64 [19.69] | 5.4756 | 56.70 [22.60] | 7.2078 | −11.931 | <0.001 |
| Ideal weight (kg)[BMI] | 43.99 [17.45] | 4.1112 | 48.10 [19.19] | 4.176 | −11.282 | <0.001 |
| Weight perceived as unacceptable (kg) [BMI] | 49.60 [19.67] | 5.3845 | 56.73 [22.62] | 7.7233 | −11.449 | <0.001 |
| Weight perceived as model shape (kg) [BMI] | 42.60 [16.89] | 4.1598 | 44.79 [17.88] | 3.816 | −6.120 | <0.001 |
| Weight perceived as obese (kg) [BMI] | 52.95 [21.01] | 6.7498 | 58.40 [23.32] | 7.0286 | −9.034 | <0.001 |
| Age at which weight gain became a concern (years)§ (n = 321/171) | 19.22 | 4.85 | 18.94 | 5.58 | 0.560 | 0.576 |
| Age decided to diet (years) ‖ (n = 220/135) | 17.45 | 3.70 | 17.99 | 4.09 | −1.277 | 0.203 |
| Annual income * (yes) (%) † | χ 2 | p | ||||
| ≧2,000,000 yen | 34.5% | 36.0% | 3.940 | 0.685 | ||
| 2,000,000 yen~>4,000,000 yen | 31.8% | 32.3% | ||||
| 4,000,000 yen~>6,000,000 yen | 10.0% | 13.2% | ||||
| 6,000,000 yen~>8,000,000 yen | 3.5% | 3.2% | ||||
| 8,000,000 yen~>10,000,000 yen | 1.8% | 0.5% | ||||
| I do not know | 7.5% | 5.3% | ||||
| I prefer not to answer | 11.0% | 9.5% | ||||
| (b) Diet experience, Body image, weight fluctuation, gaining weight† | χ 2 | p | ||||
| b1. Diet experience (yes) (%) | 55.00% | 71.43% | 14.467 | <0.001 | ||
| b2. Body image (Skinny/Normal /Obese) (%) | 62.5%**/29.0%/8.5% | 12.2%/42.3%**/45.5%** | 163.261 | <0.001 | ||
| b3. Body shape satisfaction (Dissatisfied/Normal/Satisfied) (%) | 19.5%/68.0%**/12.5%** | 42.9%**/52.9%/4.2% | 39.476 | <0.001 | ||
| b4. Weight fluctuation (Easy to lose/Unchanged/Easy to gain) (%) | 18.5%**/52.8%**/28.7% | 5.3%/35.4%/59.3%** | 54.842 | <0.001 | ||
| b5. Want to gain more weight (Disagree/Neutral/Agree) (%) | 54.5% /30.5%/15.0%* | 66.7%**/25.4%/7.9% | 9.440 | <0.001 | ||
| (c) Exercise habits† | χ 2 | p | ||||
| c1. Exercise habits in the past year (at least once a week) (yes %) | 51.7% | 50.30% | 0.113 | 0.736 | ||
| c2. Elementary school age (yes %) | 53.0% | 52.40% | 0.020 | 0.888 | ||
| c3. Junior high school age (club activities) (yes %) | 48.50% | 55.60% | 2.556 | 0.110 | ||
| c4. High school age (club activities) (yes/no/N/A¶) (%) | 30.0%/57.8%/12.3% | 27.0%/58.2%/14.8% | 1.052 | 0.591 | ||
| c5. Sports to continue throughout your life (Individual/Group/None) | 34.5%/7.5%/58.0% | 28.6%/12.7%/58.7% | 5.179 | 0.075 | ||
| c6. Current exercise habits are important (Disagree/Neutral/Agree) | 9.0%/43.0%/48.0% | 13.8%/46.6%/39.7% | 5.086 | 0.079 | ||
| c7. Future exercise habits are important (Disagree/Neutral/Agree) | 7.2%/41.5%/51.2% | 9.0%/41.8%/49.2% | 0.61 | 0.737 | ||
| c8. Going to have an exercise routine in future (Disagree/Neutral/Agree) | 12.0%/51.2%/36.8% | 12.7%/51.3%/36.0% | 0.07 | 0.965 | ||
| c9. Going to take specific actions for exercise habits (Disagree/Neutral/Agree) | 15.8%/56.3%/28.0% | 17.5%/58.7%/23.8% | 0.07 | 0.965 | ||
| (c-1) Reasons for exercise habits§ (n = 210/92) † | χ2 | p | ||||
| c-1-1. Health and fitness (yes %) | 87.1% | 82.1% | 1.517 | 0.218 | ||
| c-1-2. Fun or Distractions (yes %) | 72.0% | 66.3% | 0.999 | 0.318 | ||
| c-1-3. To feel inadequate in physical exercise (yes %) | 81.6% | 82.1% | 0.009 | 0.923 | ||
| c-1-4. For spiritual cultivation or training (yes %) | 31.4% | 28.4% | 0.273 | 0.601 | ||
| c-1-5. To improve my record or ability (yes %) | 27.5% | 30.5% | 0.286 | 0.593 | ||
| c-1-6. To contact family (yes %) | 16.9% | 24.2% | 2.238 | 0.135 | ||
| c-1-7. Socializing with friends and colleagues (yes %) | 25.1% | 26.3% | 0.049 | 0.825 | ||
| c-1-8. Beauty and obesity reduction (yes %) | 61.4% | 68.4% | 1.41 | 0.236 | ||
| c-1-9. Club activities (yes %) | 9.7% | 12.6% | 0.61 | 0.436 | ||
| c-1-10. To relieve stress (yes %) | 52.7% | 48.4% | 0.47 | 0.494 | ||
| (c-2) Reasons for not having exercise habits (n = 190/97)† | χ 2 | p | ||||
| c-2-1. Too busy (yes %) | 58.5% | 61.7% | 0.261 | 0.609 | ||
| c-2-2. Physically weak (yes %) | 10.9% | 9.6% | 0.115 | 0.734 | ||
| c-2-3. Old age (yes %) | 15.0% | 13.8% | 0.072 | 0.788 | ||
| c-2-4. No place or facilities (yes %) | 39.4% | 29.8% | 2.517 | 0.113 | ||
| c-2-5. Do not have friends (yes %) | 36.3% | 31.9% | 0.528 | 0.467 | ||
| c-2-6. Do not have a mentor (yes %) | 14.5% | 17.0% | 0.308 | 0.579 | ||
| c-2-7. Costs money (yes %) | 43.5% | 42.6% | 0.024 | 0.876 | ||
| c-2-8. Do not like exercise/sports (yes %) | 57.5% | 54.3% | 0.273 | 0.601 | ||
| c-2-9. Never had the chance (yes %) | 60.6% | 60.6% | 0.000 | 0.998 | ||
| (d) Eating habits† | χ 2 | p | ||||
| d1. Current food intake is good (Good/Neutral/Problematic) (%) | 40.5%/31.5%/28.0% | 43.4%/28.0%/28.6% | 0.778 | 0.678 | ||
| d2. I get the nutrients needed from my daily diet (Adequate/Sufficient/Insufficient) (%) | 5.8%/60.8%/33.5% | 5.8%/59.8%/34.4% | 0.051 | 0.975 | ||
| d3. Current eating habits are important (Disagree/Neutral/Agree) (%) | 6.8%/42.8%/50.5%* | 13.2%** /45.5%/41.3% | 8.623 | 0.013 | ||
| d4. Future eating habits are important (Disagree/Neutral/Agree) (%) | 5.8%/38.5%/55.8% | 11.1%*/40.2%/48.7% | 6.235 | 0.044 | ||
| d5. Want to have the right eating habits (Disagree/Neutral/Agree) (%) | 9.0%/43.0%/48.0%* | 12.7%/49.7%/37.6% | 6.142 | 0.046 | ||
| d6. Will take action to develop good eating habits (Disagree/Neutral/Agree) (%) | 10.5%/55.8%/33.8%** | 19.0%**/60.3%/20.6% | 15.023 | <0.001 | ||
| d7. Want to increase food intake (Disagree/Neutral/Agree) (%) | 41.5%/45.5%/13.0%* | 51.9%*/41.8%/6.3% | 8.690 | 0.013 | ||
| d8. Frequency of missing meals (Every day/Several times a week/None at all) (%) | 15.9%/25.4%/58.7% | 17.0%/19.1%/63.8% | 0.533 | 0.766 | ||
| d10. Stress and fatigue changed appetite (Decrease/No change/Over-eat) (%) | 28.5%/33.5%/38.0% | 21.7%/33.9%/44.4% | 3.595 | 0.166 | ||
*Annual income: Salaried full-time employees who had an average salary of 4,430,000 yen (men: 5,450,000 yen; women: 3,020000 yen) (18).
†
Chi-square test results. *p < 0.05, **p < 0.01.
‡
Data for 493 participants recorded in the Maternal and Child Health Handbook.
§
Data from 492 respondents who were concerned about weight gain.
‖
Data from 189 respondents who have diet experience.
¶
N/A is not applicable (participants who have not been enrolled in high school).