Table 2

Studies Reporting Prevalence of Multimorbidity in the General Population

		Sample			Methods

Study (Year)	Country	No. of Individuals	Age, y	Recruitment	Data Collection	No. of Diagnoses Considered
Verbrugge et al (1989)²⁷	United States	16,148	≥55	1984 National Health Interview Survey, the Supplement on Aging	Questionnaire completed by interview	13
Newacheck et al (1991)²⁴	United States	7,465	10–17	1988 National Health Interview Survey on Child Health	Questionnaire completed by interview	>50
Hoffman et al (1996)²²	United States	27,505	All	1987 National Medical Expenditure Survey	Questionnaire completed by interview	All chronic conditions classified in ICD-9 codes
Fuchs et al (1998)²⁶	Israel	1,487	75–94	A national random stratified sample	Questionnaire completed by interview	14
Menotti et al (2001)²⁰	Finland, The Netherlands, Italy	716 (Finland), 887 (the Netherlands), and 682 (Italy)	Men 65–84	Cohorts recruited in particular locations	Clinical examination	7
Rapoport et al (2004)²⁵	Canada	17,244	>20	1999 National Population Health Survey	Questionnaire completed by interview	22
Partnership for Solutions (2004)²⁹	United States	(Not reported)	All	2001 National Medical Expenditure Survey	Questionnaire completed by interview	All chronic conditions classified in ICD-9 codes
Naughton et al (2006)²³	Ireland	316,928		Individuals from a national pharmacy claims database	Conditions identified from ≥3 dispensed items associated with a specific chronic condition	9
Nagel et al (2008)²¹	Germany	13,781	50–75	Participants in the EPIC subcohort of Heidelberg recruited from the general population	Questionnaire completed by interview	13 diagnostic groups
Marengoni et al (2008)¹⁹	Sweden	1,099	77–100	Inhabitants of the Kungsholmen area in Stockholm	Clinical assessment, medical history, laboratory data, and current drug use	All chronic conditions
Schram et al (2008)³⁰	The Netherlands	1,691+1,002 (LASA), 7,983 (Rotterdam), and 599 (Leiden)	55–94 (LASA), ≥65 (Rotterdam), 85 (Leiden)	Inhabitants of the different geographic locations	Medical history from self-reports as well as from the GP (LASA); an extensive physical examination (Rotterdam); medical history obtained from GP or treating nursing home physician (Leiden)	Varied by location: 12 diagnoses (LASA), 12 diagnoses (Rotterdam), and 13 diagnoses (Leiden)
Cazale and Dumitru (2008)²⁸	Canada	~26,000	≥12	Quebec residents included in the 2005 National Population Health Survey	Questionnaire completed by interview	7
Loza et al (2009)¹⁸	Spain	2,192	>20	National random sample taking into account the Spanish rural-urban ratio	Questionnaire completed by interview	All diseases

EPIC = European Prospective Investigation into Cancer and Nutrition; GP = general practitioner; ICD-9=International Classification of Diseases, Ninth Revision; LASA=Longitudinal Aging Study Amsterdam.