Table 1

The general characteristics of the study population

General characteristicsChildren (tonsillectomy/adenotonsillectomy)Adults (tonsillectomy)
Of the study populationIntervention groupControl groupP valueIntervention groupControl groupP value
n=522n=522n=1122n=1122
Age1.001.00
 0–4137 (26.2%)137 (26.2%)
 5–6126 (24.1%)126 (24.1%)
 7–14259 (49.6%)259 (49.6%)
 15–391046 (93.2%)1046 (93.2%)
 40–76 (6.8%)76 (6.8%)
Age at surgery7.75 (3.49)
6.98 (1.70 to 14.99)
(7.45 to 8.05)
7.26 (3.36)
6.97 (0.53 to 14.99)
(6.97 to 7.55)
25.1 (8.7)
22.1 (15.0 to 78.2)
(24.6 to 25.6)
28.2 (9.7)
26.9 (15.0 to 88.7)
(27.7 to 28.8)
 Gender1.001.00
 Male256 (49.0%)256 (49.0%)352 (31.4%)352 (31.4%)
 Female266 (51.0%)266 (51.0%)770 (68.6%)770 (68.6%)
Medical care visits (prior to surgery/no surgery)<0.0001<0.0001
 Primary care physician1624 (80.8%)1841 (93.5%)2593 (79.8%)3004 (93.5%)
 Specialist (public care)316 (15.7%)105 (5.3%)530 (16.3%)178 (5.5%)
 Specialist (private care)71 (3.5%)22 (1.1%)125 (3.8%)32 (1.0%)
Number of medical care visits 2 years prior to surgery/no surgery1.001.00
 187 (16.7%)87 (16.7%)330 (29.4%)330 (29.4%)
 2100 (19.2%)100 (19.2%)240 (21.4%)240 (21.4%)
 394 (18.0%)94 (18.0%)216 (19.3%)216 (19.3%)
 478 (14.9%)78 (14.9%)130 (11.6%)130 (11.6%)
 553 (10.2%)53 (10.2%)89 (7.9%)89 (7.9%)
 631 (5.9%)31 (5.9%)72 (6.4%)72 (6.4%)
 7+79 (15.1%)79 (15.1%)45 (4.0%)45 (4.0%)
 Average3.85 (2.56)
3 (1 to 17)
(3.63 to 4.07)
3.77 (2.34)
3 (1 to 14)
(3.57 to 3.97)
2.89 (1.99)
2 (1 to 21)
(2.78 to 3.01)
2.86 (1.86)
2 (1 to 15)
(2.76 to 2.97)
Category (visits before surgery/no surgery)1.001.00
 A: 1–3 visits281 (53.8%)281 (53.8%)786 (70.1%)786 (70.1%)
 B: 4–6 visits162 (31.0%)162 (31.0%)291 (25.9%)291 (25.9%)
 C: 7+ visits79 (15.1%)79 (15.1%)45 (4.0%)45 (4.0%)
Follow-up
 1-year follow-up5225221.00112211221.00
 2-year follow-up419 (80.3%)437 (83.7%)0.17892 (79.5%)922 (82.2%)0.12
 3-year follow-up304 (58.2%)357 (68.4%)0.0008659 (58.7%)697 (62.1%)0.11
  • For categorical variables, n (%) is presented. For continuous variables, mean (SD)/median (min; max)/(95% CI for mean) is presented.