Mortensson 1984.

Methods	Study design: quasi‐randomised controlled trial (allocation via date of birth); 2‐arm study Study duration: not stated
Participants	Setting: not stated Location: St Goran's Children's Hospital, Stockholm, Sweden Health status: intussusception radiologically confirmed by barium enema Number (treatment/control): 188 (69/119) Age (median): 1 month to 5 ½ years (9 months) Sex (M/F): not stated Exclusion criteria: intestinal obstruction and clinical suspicion of bowel gangrene, clinical and radiological manifestations of peritonitis, high fever with gross bowel obstruction
Interventions	Following diagnosis by barium enema, groups were allocated to 2 groups Treatment group Glucagon: 0.05 mg/kg injected IM, 5 minutes before barium enema reduction Control group Barium enema reduction, 5 minutes after diagnosis by barium enema, similar to treatment group
Outcomes	Rate of successful intussusception reduction Number of attempts until successful enema reduction of intussusception Time until successful reduction of intussusception with enema
Notes	Procedure details: The pressure of the enema employed was kept as uniform as possible, corresponding to 100 to 120 cm of barium suspension Reduction was considered a failure when an intussusception could no longer be moved in an oral direction after several minutes of effective pressure 5 minutes after a first attempt had failed, a second and later a third attempt was made. Failure after this point meant that the participant was prepared for operation. Participants in the control group with 3 failed attempts were administered IV glucagon, as in the treatment group, and an attempt at hydrostatic reduction was repeated. After a fourth attempt, these participants were prepared for operation Other details: Study was undertaken in 3 steps (Step 1: initial 3 attempts at reduction as per treatment group; Step 2: participants belonging to the control group were administered glucagon and a fourth attempt was made at reduction; participants with reduction regarded as a failure were prepared for surgery; Step 3: all other participants otherwise not reduced were given a final attempt at reduction before they were prepared for surgery). We have included data only for Step 1, as this step pertains to our outcomes and criteria for inclusion
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Allocation of material to a test group and a reference group according to date of birth; participants born on an even calendar date were given an intramuscular injection of 0.05 mg glucagon/kg body weight
Allocation concealment (selection bias)	Unclear risk	Unclear who allocated participants, and who administered treatment
Incomplete outcome data (attrition bias) All outcomes	High risk	Not stated why some participants from reference group or control group progressed to steps 2 and 3, and why others were excluded
Selective reporting (reporting bias)	Unclear risk	No protocol available. Not all expected outcomes were reported
Blinding of participants and personnel (performance bias) All outcomes	High risk	No placebo given Treatment group given intramuscular injection; control group given no injection
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	It was not specified who assessed outcomes