Maurer 1973.

Study characteristics
Methods	Single‐centre, randomised controlled trial conducted in USA
Participants	Inclusion criteria: infants < 2500 grams; postnatal age < 24 hours  Exclusion criteria: positive Coombs' tests; potential ABO incompatibility; sepsis
Interventions	Total N = 69  Group 1 (n = 17): 125 mg of agar given with feeds every 3 hours for 4 days beginning at 18 hours Group 2 (n = 18): intermittent phototherapy (12 hours daily for 4 days) Group 3 (n = 19): continuous phototherapy (4 days) Group 4 (n = 15): no intervention
Outcomes	Primary and secondary outcomes Not specified Reported outcomes Daily serum bilirubin concentrations for 6 days
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Sequence generation not described ((quote:) "infants ... were randomly assigned to one of four groups").
Allocation concealment (selection bias)	Unclear risk	Allocation concealment not described ((quote:) "infants ... were randomly assigned to one of four groups").
Blinding (performance bias and detection bias) All outcomes	Low risk	Unblinded study with objective outcome measures
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Unblinded study with objective outcome measures
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Unblinded study with objective outcome measures
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Completeness of data not specified
Selective reporting (reporting bias)	Unclear risk	Study protocol not available
Other bias	Low risk	No other potential sources of bias were identified.