Table 1.

Characteristics of studies regarding the epidemiology of constipation in Europe in the general population.

First author, year of publication, setting	Type of study	Definition of constipation	Study population (% of responders)	Prevalence per 100	Factors significantly associated with increased odds for constipation	Quality score+	Comments
Siproudhis L 2005 France [16]	Mailed questionnaire survey	Emptying difficulties or unsatisfied defecation during the preceding 12-month period	7196 (72) persons ≥ 15 yr, representative of the general population	22.4	History of vaginal delivery in women	6	F/M 2
Garrigues V 2004 Spain [17]	Mailed questionnaire study	Self-reported, Rome I, and Rome II criteria	349 (71.4) participants, 18–65 yr, representative of the general population	29.5 (self-reported) 19.2 (Rome I criteria) 14 (Rome II criteria)	Female gender	7	F/M 2.2 Agreement between self-reported and Rome II criteria was moderate
Walter S 2002 Sweden [18]	Mailed questionnaire study	Self-reported, as 'sometimes, often or always' constipated	1610 (80.5) persons, 31–76 yr, randomly selected	19.8 of women 8.3 of men	Female gender	4	F/M 2.4
Haug TT 2002 Norway [19]	Mailed questionnaire study	Self-reported, as 'minor or major complaints' during the last 12 months	62651 (66.5) persons, > 20 yr	20.2	Anxiety, and less strongly depression	4	F/M 4
Frexinos 1998 France [20]	Interview- questionnaire survey	Self reported	6000 (81) participants > 15 yr, selected by systematic random sampling	35		7
Gaburri 1989 Italy Umbria [21]	Interview-questionnaire survey, performed by a physician.	≤ 2 DPW for > 9 months in the last 3 years and/or straining at stool > 75% of the time	544 (98). 104 medical students, 103 medical and paramedical employees and 326 randomly selected home interviewed persons.	9.2	Female gender presented significantly higher constipation rates.	5
Bassotti G 2004 Italy [22]	Prospective study	Rome II criteria	298 (61) persons recruited from the general population and asked to compile a daily diary on their bowel habits and associated signs and symptoms	5 (< 3 DPW) 11.7(straining) 10.7(incomplete evacuation)		6

Abbreviations DPW: defecations per week, F/M: female/male ratio, Rome II criteria: at least 12 weeks, which need not be consecutive, in the preceding 12 months, of two or more of: < 3 DPW, hard or lumpy stools in > 1/4 of defecations, straining in > 1/4, digital manipulation of stools in > 1/4, sensation of incomplete evacuation in > 1/4, sensation of anorectal obstruction or blockage in > 1/4, ⁺: critical appraisal guidelines for research articles determining prevalence, developed by Loney et al¹⁴