Skip to main content

Table 3 Association between low back pain and the weight of school bag and other risk factors among 918 public high school students in Kuwait, 2017

From: Prevalence of low Back pain among adolescents in relation to the weight of school bags

Factor Odds ratio of LBP (6-month)
OR [95% CI] p-value1
Bag weight in kg
  ≤ 5.32 1.00 [Reference] 0.620
 5.33–7.35 1.17 [0.85–1.61]  
  ≥ 7.36 1.10 [0.80–1.50]  
Bag weight as percent of body weight
  < 10% 1.00[Reference] 0.041
 10 to 15% 1.42 [1.07–1.90]  
  ≥ 15% 0.95 [0.62–1.10]  
Gender
 Males 1.00 [Reference] <0.001
 Females 2.17 [1.66–2.82]  
Age (years) 0.98 [0 .87–1.11] 0.792
Nationality
 Kuwaiti 1.00 [Reference] 0.790
 Non-Kuwaiti 1.04 [0.76–1.44]  
Governorate
 Al-Jahra 1.00 [Reference] 0.102
 Hawalli 0.96 [0.62–1.49]  
 Al-Asimah (Capital) 1.11 [0.72–1.71]  
 Al-Farwaniyah 0.76 [0.49–1.18]  
 Al-Ahmadi 0.62 [0.41–0.95]  
 Mubarak Al-Kabeer 0.90 [0.55–1.46]  
Father’s education
 No formal education/ middle school 1.00 [Reference] 0.093
 High school 0.89 [0.56–1.40]  
 Diploma/university degree 1.15 [0.75–1.75]  
 Unknown 0.74 [0.46–1.20]  
Mother’s education
 No formal education/middle school 1.00 [Reference] 0.332
 High school 1.14 [0.74–1.73]  
 Diploma/university degree 1.32 [0.90–1.95]  
 Unknown 1.00 [0.63–1.60]  
Perceived heaviness of school bag1
 Light 1.00 [Reference] < 0.001
 Normal 1.24 [0.70–2.18]  
 Heavy 1.98 [1.13–3.50]  
 Very heavy 4.20 [2.19–8.06]  
Carrying a school bag ≤4 days or never3 1.00 [Reference] < 0.001
Carrying a school bag every day 2.84 [1.72–4.68]  
Number of bags taken to school
 None 1.00 [Reference] < 0.001
 One 2.95 [1.76–4.97]  
 Two 4.14 [1.56–11.00]  
 More than two 8.00 [.79–81.25]  
The way of carrying school bag4
 On two shoulders 1.00 [Reference] 0.384
 On one shoulder 1.02 [0.72–1.43]  
 Others 0.54 [0.98–1.33]  
Using lockers to reduce the weight of school bag
 Yes 1.00 [Reference] 0.156
 No 0.46 [0.16–1.34]  
Walking to/from school per week5
 None 1.00 [Reference] 0.41
 1–8 times 0.78 [0.50–1.21]  
 Every day (10 times) 1.21 [0.68–2.16]  
Playing sports per week
 None 1.00 [Reference] 0.97
 Once 1.03 [0.69–1.55]  
 2–3 times 1.09 [0.76–1.58]  
 More than 3 times 1.06 [0.73–1.55]  
Watching TV/ using computer per day
  ≤ 2 h 1.00 [Reference] 0.012
 3–5 h 1.33 [0.97–1.82]  
 ≥ 6 h 1.76 [1.16–2.68]  
Using iPad/ playing videogames per day
  ≤ 2 h 1.00 [Reference] 0.492
 3–5 h 1.21 [0.88–1.66]  
 ≥ 6 h 0.99 [0.66–1.49]  
Studying/ doing homework/ reading per day
 ≤ 2 h 1.00 [Reference] 0.483
 3–5 h 1.09 [0.79–1.48]  
  ≥ 6 h 1.43 [0.78–2.62]  
Favorite place for studying at home
 Bed 1.00 [Reference] 0.963
 Desk 0.94 [0.69–1.28]  
 Floor 1.04 [0.72–1.50]  
 Couch 0.95 [0.61–1.49]  
 Other 0.63 [0.10–3.84]  
Cigarette smoking
 Non-smoker 1.00 [Reference] 0.060
 Ex-smoker 0.64 [0.38–1.09]  
 Current smoker 0.71 [0.52–1.01]  
Shisha smoking
 Non-smoker 1.00 [Reference] 0.410
 Ex-smoker 1.45 [0.64–3.26]  
 Current smoker 0.76 [0.43–1.35]  
GPA of the participant
 Less than 74% 1.00 [Reference] 0.277
 74%- less than 85% 1.16 [0.84–1.95]  
 ≥ 85% 1.29 [0.94–1.77]  
BMI categories6
 Normal/underweight 1.00 [Reference] 0.587
 Overweight 1.20 [0.85–1.70  
 Obese 0.94 [0.70–1.27]  
 Underweight 0.88 [0.33–2.31]  
  1. 1p-values were generated using likelihood ratio test
  2. 2as reported by the students and 78 students did not have school bags
  3. 378 students who did not have school bags are included in the reference group
  4. 4data were collected using a photo card and those who did not have school bags were excluded in this analysis
  5. 5going and coming from school is two times
  6. 6weight and height were measured and WHO growth charts were used to calculate z-score