Study (quality) | Intervention | Control intervention | Outcome measure | Results | Efficacy |

a: PEG compared to placebo | |||||

Thomson et al 200742 (HQ) | PEG+E, starting dose: <7 yrs 6.9 g/day, 7–11 yrs 13.8 g/day | Placebo | Mean defecation frequency/week | Mean (SD) I: 3.12 (2.05). Mean (SD) C: 1.45 (1.2) (p<0.001) | More effective ns |

Faecal incontinence | Mean (SD) I: 4.70 (6.3). Mean (SD) C: 4.85 (7.9) | ||||

b: PEG compared to lactulose | |||||

Candy et al 200620 (HQ) | PEG+E, starting with half the dosage required for disimpaction/day | Lactulose, starting with half the dosage required for disimpaction/day | Mean defecation frequency/week | Mean (SD) I: 9.4 (4.6). Mean (SD) C: 5.9 (4.3) (p = 0.007) | More effective |

Voskuijl et al 200446 (HQ) | PEG 3350, starting dose <6 yrs 2.95 g/day, >6 yrs 5.9 g/day | Lactulose, starting dose <6 yrs 6 g/day, >6 yrs 12 g/day | Mean defecation frequency/week | Mean (SD) I: 7.1 (5.1). Mean (SD) C: 6.4 (5.2) (p = 0.505) | ns |

Treatment success (⩾3 BMs/week and no soiling) | I: 31/50 (63%). C: 23/50 (47%) (p = 0.013) | More effective | |||

Dupont et al 200523 (LQ) | PEG 4000, starting dose 4 g/day | Lactulose, starting dose 3.33 g/day | Median defecation frequency/week | I: 8.5 (range 7.5–12.5) in babies, 7 (5–8) in toddlers. C: 11.5 (9–13) in babies, 6 (4–7) in toddlers | ns |

Children with soft/normal stools | I: 44/47 (93.6%). C: 29/40 (72.5%) (p = 0.008) | More effective | |||

Gremse et al 200225 (LQ) | PEG 3350, 10 g/m2/day | Lactulose, 1.3 g/kg/day | Mean defecation frequency/2 weeks | Mean (SD) I: 14.8 (1.4). Mean (SD) C: 13.5 (1.5) (p<0.05) | More effective |

Global assessment of treatment success | I: 31/37 (84%). C: 17/37 (45.9%) (p = 0.002) | More effective | |||

Wang et al 200748 (HQ) | PEG 4000, 20 g/day | Lactulose, 15 g/day | Median defecation frequency/week | I: 7. C: 6. I: 76/105 (72%) | ns |

Children in clinical remission of constipation | C: 45/111 (41%) (p<0.01) | More effective | |||

c: PEG compared to other laxatives | |||||

Tolia et al 199343 (LQ) | PEG 3350, 20 ml/kg/h | Mineral oil, 30 ml/10 kg | Children with >1 BM after treatment | I: 17/19 (89%). C: 12/17 (71%) (p<0.005) | More effective |

Loening-Baucke 200229 (LQ) | PEG 3350, starting dose 0.5 or 1 g/kg/day | Milk of magnesia, starting dose 1 or 2.5 ml/kg/day | Treatment success (⩾3 BMs/week and ⩽2 soiling episodes per month) | I: 17/28 (61%). C: 14/21 (67%) (p = 0.67) | ns |

Loening-Baucke et al 200631 (LQ) | PEG 3350, 0.7 g/kg body weight PEG daily | Milk of magnesia, 2 ml/kg body weight daily | Improvement (⩾3 BMs/week and ⩽2 soiling episodes/month; no abdominal pain) | I: 24/39 (62%). C: 17/40 (43%) (p = 0.086) | ns |

d: Lactulose compared to other laxatives | |||||

Perkin 197737 (LQ) | Lactulose, 10–15 ml/day | Senna, 10–20 ml/day | Mean defecation frequency/week | Mean (SD) I: 18.1 (2.0). Mean (SD) C: 17.1 (1.5) (p = 0.075) | ns |

Urganci et al 200544 (LQ) | Lactulose, starting dose 1 ml/kg twice/day | Liquid paraffin, starting dose 1 ml/kg twice/day | Mean defecation frequency/week | Mean (SD) I: 12.3 (6.6). Mean (SD) C: 16.1 (2.2) (p<0.05) | less effective |

e: Cisapride | |||||

Halabi et al 199926 (LQ) | Cisapride | Placebo | Mean defecation frequency/week | Mean (SD) I: 6.7 (0.9). Mean (SD) C: 1.3 (0.9) (p<0.0001) | More effective |

Ni et al 200134 (LQ) | Cisapride, 0.2 mg/kg 3 dd + MgO 125 or 250 mg 3 times/day | Magnesium oxide, 125 or 250 mg 3 times/day | Children with ⩾3 BMs/week | I: 40/44 (91%). C: 27/40 (67%) (p = 0.013) | More effective |

Nurko et al 200036 (HQ) | Cisapride, 0.2 mg/kg/dose 3 times/day | Placebo | Mean defecation frequency/week | Mean (SD) I: 4.1 (1.1). Mean (SD) C: 2.2 (0.6) (p>0.05) | ns |

f: Senna | |||||

Berg et al 198316 (LQ) | Senna, starting dose one tablet | Placebo (C1), starting dose one tablet. No medication (C2) | Relief of soiling (on a 4-point scale indicating frequency of soiling) | I: 5/14 (55%). C1: 7/11 (64%) p = 0.16. C2: 6/15 (66%) (p = 0.81) | ns |

Perkin 197737 (LQ) | Senna, 10–20 ml/day | Lactulose, 10–15 ml/day | Mean defecation frequency/week | Mean (SD) I: 17.1 (1.5). Mean (SD) C: 18.1 (2.0) (p = 0.075) | ns |

Sondheimer et al 198140 (LQ) | Senna, in doses sufficient to induce 1 BM/day | Mineral oil, twice/day in doses sufficient to induce loose stools rectal oil leakage | Children with daily BMs | I: 9/18 (50%). C: 16/19 (89%) (p<0.05) | Less effective |

g: Mineral oil | |||||

Sondheimer et al 198140 (LQ) | Mineral oil, twice/day in doses sufficient to induce loose stools rectal oil leakage | Senna, in doses sufficient to induce 1 BM/day | Children with daily BMs | I: 16/19 (89%). C: 9/18 (50%) (p<0.05) | More effective |

Tolia et al 199343 (LQ) | Mineral oil, 30 ml/10 kg | PEG 3350, 20 ml/kg/h | Children with >1 BM after treatment | I: 12/17 (71%). C: 17/19 (89%) (p<0.005) | Less effective |

Wald et al 198747 (LQ) | Mineral oil 1–4 tablespoons/day | Biofeedback | Children with <1 soiling episode/week | I: 13/26 (50%). C: 14/24 (60%) (p = 0.47) | ns |

h: Fibre | |||||

Castillejo et al 200621 (HQ) | Cocoa husk supplement (fibre), 3–6 yrs: two sachets ( = 8 mg)/day; 7–10 yrs: four sachets ( = 16 mg)/day | Placebo, 3–6 yrs: two sachets/day; 7–10 yrs: four sachets/day | Mean defecation frequency/week | Mean (SD) I: 6.2 (3.3). Mean (SD) C: 5.1 (2.1) (p = 0.78) | ns |

Loening-Baucke et al 200430 (LQ) | Glucomannan (fibre), 100 mg/kg/day | Placebo (maltodextrins), 100 mg/kg/day | Mean defecation frequency/week | Mean (SD) I: 4.5 (2.3). Mean (SD) C: 3.8 (2.2) (p = 0.139) | ns |

i: Laxatives investigated in one single study | |||||

Banaszkiewicz et al 200514 (HQ) | Lactobacillus GG, 109 colony-forming units twice/day +70% lactulose 1 ml/kg/day | Placebo +70% lactulose, 1 ml/kg/day | Mean defecation frequency/week at 12 weeks | Mean (SD) I: 6.1 (1.8). Mean (SD) C: 6.8 (3.1) (p = 0.5) | ns |

Bellomo-Brandao et al 200315 (LQ) | Erythromycine estolate, 20 g/kg/day | Placebo | Improvement of constipation (based on stool frequency, soiling, faecal impaction, faecal consistency and pain at stool passage) | End phase 1: mean (SD) E-P: 2.2 (1.0). Mean (SD) P-E: 2.9 (2.8). End phase 2: mean (SD) E-P: 4.3 (2.3). Mean (SD) P-E: 2.4 (2.1) (E vs P: p = 0.006) | More effective |

Bongers et al 200717 (HQ) | New formula with high concentration of sn-2 palmitic acid, a mixture of prebiotic oligosaccharides and partially hydrolysed whey protein (Nutrilon Omneo) | Standard formula (Nutrilon 1) | Mean defecation frequency/week | Mean (SD) I: 5.6 (2.8). Mean (SD) C: 4.9 (2.5) (p = 0.36) | ns |

Improvement of hard to soft stools | Mean (SD) I: 9/10 (90%). Mean (SD) C: 5/10 (50%) (p = 0.14) | ns | |||

Bu et al 200719 (HQ) | Lactobacillus casei rhamnosus (Lcr35), 8×108 colony-forming units/day | Magnesium oxide (C1), 50 mg/kg/day. Placebo (C2) | Mean defecation frequency/day | Mean (SD) I: 0.6 (0.2). Mean (SD) C1: 0.5 (0.1) (p = 0.77). Mean (SD) C2: 0.4 (0.1) (p = 0.006) | ns |

More effective | |||||

Chao et al 200722 (LQ) | Magnesium-enriched infant formula (Novalac-IT) | 20%-strengthened infant formula | Improvement of constipation (based on stool consistency, frequency and volume, and defecation difficulties) | I: 42/47 (89%). C: 25/46 (54%) (p<0.001) | More effective |

Nolan et al 199135 (LQ) | Senna and/or bisacodyl and/or agarol | Standard paediatric behaviour modification | Treatment succes | I: 42/83 (51%). C: 31/86 (36%) (p = 0.079) | ns |

Zoppi et al 199850 (LQ) | Calcium polycarbophil, 0.62/g 3 times/day | Placebo | Children with disappearance of constipation (1 BM/day, soft stools) | I: 6/14 (43%). C: 0/14 (0%) (p⩽0.01) | More effective |

BM, bowel movement; C, control intervention; HQ, high methodological quality; I, intervention under study; LQ, low methodological quality; ns, not significant.