TABLE 2.

Risk of bias¹

Reference	RSG and AC (selection bias)2	Blinding of participants and personnel (performance bias)	Blinding of outcome assessment (detection bias)	Incomplete outcome data (attrition bias)
Koletzko et al. (ECOT study) (33)	Low risk of both RSG and AC: randomization in permuted blocks based on an internet platform	Low risk	Unclear risk	High risk: >40% of infants did not follow-up at 24 mo
Escribano et al. (ECOT study) (34)	Low risk of both RSG and AC: randomization in permuted blocks based on an internet platform	Low risk	Unclear risk	High risk: >40% of infants did not follow-up at 24 mo
Weber et al. (ECOT study) (35)	Low risk of both RSG and AC: randomization in permuted blocks based on an internet platform	Low risk	Unclear risk	High risk: 52% of infants did not follow-up at 6 y
Timby et al. (36)	Low risk of RSG: computer randomization in blocks of 8; unclear risk of AC	Low risk	Unclear risk	Medium risk: only 11% of infants lost to follow-up
Inostroza et al. (37)	Unclear risk of both RSG and AC	Low risk	Unclear risk	Medium risk: 16% of infants lost to follow-up at 6 mo
Akeson et al. (38)	Unclear risk of RSG and AC	Low risk	Unclear risk	Medium risk: <10% of infants lost to follow-up

¹AC, allocation concealment; ECOT, European Childhood Obesity Trial; RSG, random sequence generation.

²Each category of risk of bias was assessed as low risk if there were no concerns, unclear risk if not explicitly stated in the study report, and high risk if there were concerns of bias. For incomplete outcome data, <5% was considered low risk, 5–20% was considered medium risk, and >20% was considered high risk of bias.