Table 2

Sensitivity analyses of efficacy of osmotic and stimulant laxatives in chronic idiopathic constipation

	Number of studies	Number of subjects	RR of failure to respond to therapy	95% CI	I² value	Number needed to treat	95% CI
All studies	7	1411	0.52	0.46 to 0.60	42%	3	2 to 4
Risk of bias of trials
Low	5	1260	0.54	0.46 to 0.62	52%	3	2 to 4
High	2	151	0.41	0.26 to 0.65	N/A	3	2 to 6
Definition of CIC
Rome criteria-defined	5	1157	0.52	0.45 to 0.61	50%	2.5	2 to 3
Other definition	2	254	0.51	0.27 to 0.96	N/A	4.5	3 to 9
Duration of therapy
≤ 4 weeks	4	989	0.54	0.45 to 0.66	51%	3	2.5 to 4
> 4 weeks	3	422	0.46	0.33 to 0.65	49%	2.5	2 to 3
Definition of response to therapy
≥3 stools per week	4	573	0.52	0.41 to 0.65	36%	3	2 to 4
≥3 CSBMs per week	2	735	0.54	0.42 to 0.69	NA	3	2 to 3.5

N/A, not applicable (too few studies to assess heterogeneity); CIC, chronic idiopathic constipation; CSBM, complete spontaneous bowel movement.