Densert 2001.

Study characteristics
Methods	Single‐blinded, parallel ‐group randomised controlled surgical trial with 2‐year duration of follow‐up
Participants	Setting: ENT clinic, Halmstad, Sweden Sample size: Number randomised: 43 children Number completed: 41 children Participant (baseline) characteristics: Age: 2 to 9 years Gender: 42% males, 58% females Inclusion criteria: children were included in the study on the basis of symptoms of OSAS. Snoring and apnoea were the most frequently reported symptoms. Dysfunctional problems such as reluctance to eat, daytime sleepiness hyperactivity, irritability and aggression were also reported as frequent occurrences. The patient history was obtained from the parents and a thorough physical examination of the children was performed. When the symptoms of OSAS persisted after 3 to 4 months the patients were scheduled for surgery, the hypertrophic tonsils being the probable cause of the symptoms Exclusion criteria: tonsil problems caused by infections, anatomic or neurological conditions, allergy
Interventions	Intervention group: tonsillectomy (TE) by blunt dissection (n = unknown) Comparator group: tonsillotomy (TT) by CO2 laser (n = unknown) Use of additional interventions: all patients had previously received adenoidectomy
Outcomes	Short‐term outcomes (1 day): surgical time, intraoperative bleeding, postoperative bleeding, postoperative pain Long‐term outcomes (3 months, 2 years): oSDB symptoms, frequency of infections (throat and catarrhal)
Notes	Participants lost to short‐term (3‐month) follow‐up: 0% Participants lost to long‐term (2‐year) follow‐up: 5% (1 per group)
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "On the day of surgery, the patients were randomized into one of two groups to undergo either a standard TE or a TT using a CO2 laser. The patients were randomized in blocks of 10"
Allocation concealment (selection bias)	Unclear risk	Method not described
Blinding of participants and personnel (performance bias) All outcomes	High risk	Patients and personnel not blinded
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "The patient data were blinded and evaluated by a researcher and a statistician who did not have any direct communication with or knowledge of the patients"
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No protocol available; insufficient information to permit a judgement of low or high risk
Selective reporting (reporting bias)	High risk	Number of participants randomised to each group not stated
Other bias	Unclear risk	Baseline characteristics: balanced ITT analysis: unclear if performed Formal sample size calculations: not performed Use of co‐interventions: balanced across groups (all had previously received adenoidectomy)