Table 1

Characteristics of the studies included in the meta-analysis

First author, year	Study design	Location	Participants	Population	Mean age (years)	IBS diagnosis criteria	Prevalence	2*2 table	ACE evaluation criteria	OR (95% CI)
Berens, 202026	Cross-sectional	Germany	381	Adults	36.17 IBS 29.45 control	Rome III	ACE in IBS=63.7% ACE in non-IBS=48%	A=81 B=61 C=46 D=66	ACE criteria (10Q)	1.90 (1.15 to 3.14)
Bradford, 201212	Cross-sectional	USA	729	Adults	23.4 IBS 35.1 control	Rome III with physician evaluation for FGID	ACE in IBS=76.6% ACE in non-IBS=36%	A=225.2 B=156.4 C=68.8 D=278.6	ETI-SR	5.83 (4.18 to 8.14)
Chandan, 202041	Retrospective cohort	UK	241,971	Adults	23.4 all	THIN diagnostic codes	ACE in IBS=33.1% ACE in non-IBS=N/A	A=77 889 B=N/A C=1 57 095 D=N/A	Exposure code from EMR	1.27 (1.19 to 1.35)
Fuller-Thompson, 201142	Cross-sectional	Canada	7342	Adults and children	Not listed	Self-Reported Physician Diagnosis	Not listed	Not listed	Canadian Community Health Survey	1.52 (2.12 to 1.09)*
Goodwin, 201335	Retrospective cohort	UK	17,415	Adults and children	Not listed	Self-reported	Not listed	Not listed	Self-reported, guardian or physician reported	1.18 (0.98 to 1.42)*
Heitkemper, 200128	Case–control	USA	Multiple distinct samples		Multiple distinct samples	BDQ, symptoms and GI diagnostic testing	ACE in IBS=41.3% ACE in non-IBS=31.4%	A=69 B=27 C=98 D=59	Structured interview	Multiple distinct samples
			88	Adult women (1989–1994)	33.5 IBS 32.7 control		ACE in IBS=52.3% ACE in non-IBS=34.1%	A=23 B=15 C=21 D=29		2.12 (0.89 to 5.00)
			165	Adult women (1994–1999)	32.3 IBS 32.1 control		ACE in IBS=37.3% ACE in non-IBS=28.6%	A=46 B=12 C=77 D=30		1.49 (0.69 to 3.20)
Heitkemper, 201143	Case–control	USA	72	Adult women	Not listed	Rome II and currently symptomatic	ACE in IBS=52.5% ACE in non-IBS=3.1%	A=21 B=1 C=19 D=31	Childhood Trauma Questionnaire	34.26 (21.22 to 2.21)
Jones, 201334	Cross-sectional	Australia	307	Adults	46.4 IBS 53.2 control	Rome I	ACE in IBS=50% ACE in non-IBS=50%	A=103.5 B=50 C=103.5 D=50	Self-reported	1.00 (1.81 to 0.62)
Ju, 202044	Case–control	USA	362	Adults	31 IBS 30 control	BSQ	ACE in IBS=70.6% ACE in non-IBS=63%	A=139 B=104 C=58 D=61	CTES	1.36 (1.14 to 1.62)
Park, 201614	Cross-sectional	USA	302	Adults	34.4 IBS 30.4 control	Rome II	ACE in IBS=75% ACE in non-IBS=58%	A=111 B=89.32 C=37 D=64.68	ACE criteria (18Q)	2.05 (1.21 to 3.48)
Rahal, 202027	Cross-sectional	Germany	824	Adults	44.59 IBS 30 control	BSQ	ACE in IBS=60.4% ACE in non-IBS=36.3%	A=223 B=165 C=146 D=290	ETI-SR	2.68 (2.02 to 3.56)
Talley, 199345	Cross-sectional	USA	104	Adults	54 IBS 58 control	BDQ with Manning Criteria	ACE in IBS=31.3% ACE in non-IBS=9.7%	A=10 B=7 C=22 D=65	30-minute semistructured interview from DSM III-R	4.22 (1.43 to 12.43)
Talley, 199430	Cross-sectional	USA	919	Adults	39.6 IBS 39.5 control	BSQ with Manning Criteria	ACE in IBS=15.4% ACE in non-IBS=9.5%	A=20 B=75 C=110 D=714	Drossman Sexual et al Questionnaire	1.73 (1.01 to 2.95)
Talley, 199832	Cross-sectional	Australia	726	Adults	45 IBS 43 control	BSQ	Not listed	Not listed	Drossman Sexual et al Questionnaire	2.02 (1.29 to 2.15)
Videlock, 200933	Cross-sectional	USA	86	Adults	40.4 IBS 37.3 control	Rome II	ACE in IBS=47.7% ACE in non-IBS=46.2%	A=21 B=18 C=23 D=21	Structured Clinical Interview from DSM IV	1.06 (0.45 to 2.53)

*Adjusted ORs.
A, IBS positive and ACE positive ; ACE, Adverse Childhood Events; B, IBS negative and ACE positive; BDQ, Bowel Disease Questionnaire; BSQ, Bowel Symptom Questionnaire; C, IBS positive and ACE negative; CTES, Childhood Trauma Event Scale; D, IBS negative and ACE Negative ; DSM, Diagnostic and Statistical Manual of Mental Disorders; EMR, Emergency Medical Records; ETI-SR, Early-Trauma Inventory Self Report; ETISR-SF, Early-Trauma Inventory Self Report-Short Form; GI, gastrointestinal; IBS, irritable bowel syndrome; THIN, The Health Improvement Network.