Table 2.

Lactulose

Authors	Study Group+ type	Methods + Key Outcomes
Voskuijl et al (2004) [51]	100 patients Study type :1b	Methods: 8 wk double blinded, multi-centre RCT: PEG 3350 vs lactulose. Results: Success greater for PEG group (56%) vs. lactulose group (29%) (less pain/straining). PEG significantly less palatable
Van Ginkel (2000) [52]	48 children Study type :2b	Methods: RCT: Biofeedback+ lactulose vs. biofeedback for 7 weeksResults: Both groups had improved encopresis (group 2 significantly better (86%) than group 1 (53%) p < 0.01).
Gremse et al (2002) [59]	44 children Study type :1b	Methods: Unblinded Crossover RCT Lactulose vs PEG 3350: 2 weeks Results: Lactulose had a significantly longer mean transit time compared to PEG 3350 (55.3 vs. 47.6 hrs, p = 0.038). Stool form, frequency, and ease of passage were similar for each laxative.
Perkin (1977) [53]	21 children Study type :2b	Methods: Randomised unblinded crossover study lactulose vs senna:3 weeks Results: Lactulose more likely to give greater number of days when normal stools were passed (p < 0.01). Side-effects significantly higher (p < 0.001) for senna.
Dupont et al (2005) [54]	96 children Study type :2b	Method: Random allocation, open label cohort study Results: More than 90% of children recovered normal bowel habits. Faecal mass in the rectum and abdominal pain were markedly reduced and appetite improved.
Keuzen-kamp et al (1996) [55]	244 patients Study type :4	Methods: Case series over 25y: median follow up of 4 years 3 phases: 1) evacuation with lactulose/bisacodyl 2)maintenance: regular toileting + wean laxatives to ensure soft stools daily 3) introduce high fibre diet +wean laxatives. Results: 66% cured, 34% still symptomatic, 12 had persistent symptoms. Of all 39% had at least one recurrence.
Connolly et al (1974) [56]	164 patients Study type :4	Methods: Open-label cross-over study: lactulose vs. irritant laxatives: (Senna/bisacodyl) 7 days Results: 58% of lactulose group vs 42% of stimulant group had normal stool.