title: Tonsillectomy Does Not Reduce Upper Respiratory Infections: A National Cohort Study.
abstract: OBJECTIVE
  The objective of this study was to compare post-operative visits for upper respiratory infections (URIs) between tonsillectomy and non-tonsillectomy participants (controls).
  
  
  METHODS
  Using the national cohort study from the Korean Health Insurance Review and Assessment Service, 1:4 matched (age, sex, income, region, and pre-operative URI visit) tonsillectomy participants (5,831) and control participants (23,324) were selected. Post-operative visits for URI were measured from 1 to 9 years post-op. The equivalence test was used. The margin of equivalence of the difference (Tonsillectomy-Control group group) was set to -0.5 to 0.5.
  
  
  RESULTS
  There was no difference between the tonsillectomy and control group in 1- to 9-year post-op visits (-0.5 < 95% CI of difference < 0.5). URI visits gradually decreased from 5.5/2 years (pre-op) to 2.1/year (at 1 year post-op) and 1.4/year (at 9 years post-op) in both tonsillectomy and control groups. In the subgroup analysis (children Vs adolescent and adults; rare Vs frequent pre-operative URI), there was no difference in the number of post-op visits for URI between the tonsillectomy and control groups (-0.5 < 95% CI of difference < 0.5).
  
  
  CONCLUSIONS
  Tonsillectomy does not provide a decrease in the number of post-operative visits for URI, and URI decreased over time whether or not a tonsillectomy was performed.
authors.affiliation: Department of Otorhinolaryngology-Head & Neck Surgery, Hallym University College of Medicine, Anyang, Korea.
authors.forename: Hyo Geun
authors.initials: HG
authors.lastname: Choi
authors.affiliation: Department of Otorhinolaryngology-Head & Neck Surgery, Hallym University College of Medicine, Anyang, Korea.
authors.forename: Bumjung
authors.initials: B
authors.lastname: Park
authors.affiliation: Department of Statistics, Hallym University, Chuncheon, Korea.
authors.forename: Songyong
authors.initials: S
authors.lastname: Sim
authors.affiliation: Department of Otorhinolaryngology-Head & Neck Surgery, Seoul National University College of Medicine, Bundang, Korea.
authors.forename: Soon-Hyun
authors.initials: SH
authors.lastname: Ahn
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000553:Ambulatory Care; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D012141:Respiratory Tract Infections / Q000517:prevention & control*; D014068:Tonsillectomy / Q000706:statistics & numerical data*; D055815:Young Adult