Table 1 Summary of included studies

Study	Study duration	Treatment	Dosage	Total n	Success	Defaecation rate
Thomson et al12	2-Week crossover	PEG 3350+E	Mean 0.6–0.7 g/kg/day	51	83%	3.12 per week
		Placebo	N/A	51	21%	1.45 per week, p<0.001
Candy et al13	12 Weeks	PEG 3350+E	Mean 11.8 g/day	28	–	9.4 per week
		Lactulose	Mean 24.1 g/day	30	–	7.9 per week, p = 0.007
Dupont et al14	12 Weeks	PEG 4000	4–8 g/day±enemas	51	–	8.5/7 per week
		Lactulose	3.33–6.66 g/day±enemas	45	–	11.5/6 per week, p = NS (results: toddlers/babies)
Voskuijl et al15	8 Weeks	PEG 3350	Mean dose 5.4 g/day	50	56%	7.1 per week
		Lactulose	Mean dose 6.7 g/day	50	26%, p = 0.02	6.4 per week, p<0.01
Gremse et al16	2-Week crossover	PEG 3350	0.3 g/kg/day	44	84%	14.8 per 2 weeks
		Lactulose	1.3 g/kg/day	44	46%, p = 0.002	13.5 per 2 weeks
Wang et al17	2 Weeks	PEG 4000	20 g/day	105	70%	7 per week (median)
		Lactulose	10 g/day	111	40%, p<0.05	6 per week, p<0.05
Loening-Baucke et al18	12 Months	PEG 3350	Mean 0.6 g/kg/day	39	62%	6.8 per week
		Milk of magnesia	Mean 1.2 ml/kg/day	40	43%, p = NS	8.2 per week, p = NS