title: Psychometric properties of the foot and ankle outcome score in a community-based study of adults with and without osteoarthritis.
abstract: OBJECTIVE
  Foot and ankle problems are common in adults, and large observational studies are needed to advance our understanding of the etiology and impact of these conditions. Valid and reliable measures of foot and ankle symptoms and physical function are necessary for this research. This study examined psychometric properties of the Foot and Ankle Outcome Score (FAOS) subscales (pain, other symptoms, activities of daily living [ADL], sport and recreational function [sport/recreation], and foot- and ankle-related quality of life [QOL]) in a large, community-based sample of African American and white men and women ages ≥50 years.
  
  
  METHODS
  Johnston County Osteoarthritis Project participants (n = 1,670) completed the 42-item FAOS (mean age 69 years, 68% women, 31% African American, mean body mass index [BMI] 31.5 kg/m(2) ). Internal consistency, test-retest reliability, convergent validity, and structural validity of each subscale were examined for the sample and for subgroups according to race, sex, age, BMI, presence of knee or hip osteoarthritis, and presence of knee, hip, or low back symptoms.
  
  
  RESULTS
  For the sample and each subgroup, Cronbach's alpha coefficients ranged from 0.95-0.97 (pain), 0.97-0.98 (ADL), 0.94-0.96 (sport/recreation), 0.89-0.92 (QOL), and 0.72-0.82 (symptoms). Correlation coefficients ranged from 0.24-0.52 for pain and symptoms subscales with foot and ankle symptoms and from 0.30-0.55 for ADL and sport/recreation subscales with the Western Ontario and McMaster Universities Osteoarthritis Index function subscale. Intraclass correlation coefficients for test-retest reliability ranged from 0.63-0.81. Items loaded on a single factor for each subscale except symptoms (2 factors).
  
  
  CONCLUSIONS
  The FAOS exhibited sufficient reliability and validity in this large cohort study.
authors.affiliation: University of North Carolina, Chapel Hill.
authors.forename: Yvonne M
authors.initials: YM
authors.lastname: Golightly
authors.forename: Robert F
authors.initials: RF
authors.lastname: Devellis
authors.forename: Amanda E
authors.initials: AE
authors.lastname: Nelson
authors.forename: Marian T
authors.initials: MT
authors.lastname: Hannan
authors.forename: L Stefan
authors.initials: LS
authors.lastname: Lohmander
authors.forename: Jordan B
authors.initials: JB
authors.lastname: Renner
authors.forename: Joanne M
authors.initials: JM
authors.lastname: Jordan
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000842:Ankle; D005260:Female; D005528:Foot; D005534:Foot Diseases; D006801:Humans; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011594:Psychometrics
references.citation: J Aging Health. 2005 Dec;17(6):734-52
references.pmid: 16377770
references.citation: Am J Epidemiol. 2004 Mar 1;159(5):491-8
references.pmid: 14977645
references.citation: Arthritis Care Res. 1995 Dec;8(4):242-50
references.pmid: 8605262
references.citation: J Rheumatol. 1988 Dec;15(12):1833-40
references.pmid: 3068365
references.citation: J Am Geriatr Soc. 1995 May;43(5):479-84
references.pmid: 7730527
references.citation: Psychol Bull. 1988 Mar;103(2):265-275
references.pmid: 3363047
references.citation: Osteoarthritis Cartilage. 2011 Jun;19(6):634-8
references.pmid: 21310252
references.citation: Rheumatology (Oxford). 2006 Jul;45(7):863-7
references.pmid: 16449369
references.citation: BMC Musculoskelet Disord. 2003 May 30;4:10
references.pmid: 12777182
references.citation: Rheumatology (Oxford). 1999 Sep;38(9):870-7
references.pmid: 10515649
references.citation: Clin Rheumatol. 2010 May;29(5):479-86
references.pmid: 20140474
references.citation: Foot Ankle Int. 2013 Aug;34(8):1140-6
references.pmid: 23513031
references.citation: Arthritis Care Res (Hoboken). 2011 May;63(5):654-9
references.pmid: 21225678
references.citation: Arthritis Care Res (Hoboken). 2011 Nov;63 Suppl 11:S229-39
references.pmid: 22588747
references.citation: J Am Podiatr Med Assoc. 2000 Sep;90(8):397-402
references.pmid: 11021051
references.citation: J Rheumatol. 2007 Jan;34(1):172-80
references.pmid: 17216685
references.citation: Ann Rheum Dis. 1999 Sep;58(9):563-8
references.pmid: 10460190
references.citation: Ann Rheum Dis. 2006 Apr;65(4):520-4
references.pmid: 16126799
references.citation: J Bone Joint Surg Br. 2001 Apr;83(3):339-44
references.pmid: 11341416
references.citation: Age Ageing. 1997 Mar;26(2):107-14
references.pmid: 9177667
references.citation: Foot Ankle Int. 2001 Oct;22(10):788-94
references.pmid: 11642530
references.citation: Am J Epidemiol. 1998 Oct 1;148(7):657-65
references.pmid: 9778172
references.citation: Arthritis Care Res (Hoboken). 2012 Nov;64(11):1756-9
references.pmid: 22674897
references.citation: J Am Podiatr Med Assoc. 2005 Nov-Dec;95(6):573-9
references.pmid: 16291849
references.citation: Pain. 2000 Mar;85(1-2):107-13
references.pmid: 10692609
references.citation: Scand J Med Sci Sports. 1998 Dec;8(6):439-48
references.pmid: 9863983
references.citation: Foot Ankle Int. 2012 Dec;33(12):1145-55
references.pmid: 23199868
references.citation: J Orthop Sports Phys Ther. 1998 Aug;28(2):88-96
references.pmid: 9699158
references.citation: J Orthop Sports Phys Ther. 1999 Aug;29(8):478-86
references.pmid: 10444738
references.citation: BMC Musculoskelet Disord. 2013 Jun 11;14:183
references.pmid: 23758917
references.citation: Rheumatol Int. 2009 Dec;30(2):169-73
references.pmid: 19370349
references.citation: J Athl Train. 2005 Mar;40(1):35-40
references.pmid: 15902322
references.citation: Arthritis Rheum. 2001 Oct;45(5):453-61
references.pmid: 11642645
references.citation: J Rheumatol. 2005 Jul;32(7):1324-30
references.pmid: 15996072
references.citation: Health Qual Life Outcomes. 2003 Nov 03;1:64
references.pmid: 14613558