Table 2.

Comparisons between CBT groups and TAU

	Telephone-CBT vs TAU				Web-CBT vs TAU
	Estimated difference or OR* (95% CI)	Test (degrees of freedom)	p value	Standardised difference†	Estimated difference or OR* (95% CI)	Test (degrees of freedom)	p value	Standardised difference†
IBS-SSS
12 months	−62·3 (−90·0 to −34·6)	−4·4 (1981)	p<0·001	0·65	−35·4 (−58·4 to −12·3)	−3·0 (251)	0·003	0·37
24 months	−40·5 (−66·0 to −15·0)	−3·1 (185)	0·002	0·42	−12·9 (−38·8 to 12·9)	−1·0 (178)	0·33	0·14
WSAS
12 months	−3·5 (−5·2 to −1·8)	−4·2 (257)	p<0·001	0·41	−2·9 (−4·5 to −1·3)	−3·5 (287)	p<0·001	0·34
24 months	−3·1 (−4·9 to −1·3)	−3·4 (211)	p<0·001	0·36	−1·9 (−3·7 to −0·1)	−2·1 (213)	0·036	0·22
HADS
12 months	−2·8 (−4·1 to −1·4)	−4·0 (211)	p<0·001	0·40	−2·2 (−3·4 to −0·9)	−3·4 (268)	0·001	0·32
24 months	−3·1 (−4·7 to −1·6)	−4·0 (184)	p<0·001	0·46	−2·7 (−4·4 to −1·0)	−3·1 (142)	0·002	0·39
PEQ responders
12 months‡	9·4 (4·5 to 19·7)	5·9 (2510)	p<0·001	..	3·6 (2·1 to 6·0)	4·7 (775)	p<0·001	..
24 months	8·3 (4·2 to 16·4)	6·1 (359)	p<0·001	..	3·3 (1·8 to 6·0)	3·9 (467)	p<0·001	..

All inferences were derived by multiple imputation as described in the Methods section. Each model used k=100 imputations. CBT=cognitive behavioural therapy. TAU=treatment as usual. IBS–SSS=Irritable Bowel Syndrome Symptom Severity Score. WSAS=Work and Social Adjustment Scale. HADS=Hospital Anxiety and Depression Scale. PEQ=Patient Enablement Questionnaire.

^*OR is presented only for PEQ responders.

^†Differences were standardised by dividing by the respective baseline SDs for IBS–SSS (95·5), WSAS (8·8), and HADS (6·9).

^‡The 12-month model included therapist effects in the telephone-CBT group, so these effects are conditioned on therapist.