title: Comparative validation of standard, picture-sort and meal-based food-frequency questionnaires adapted for an elderly population of low socio-economic status.
abstract: OBJECTIVE
  To compare the validity of a modified Block food-frequency questionnaire (FFQ), a picture-sort administration of the FFQ (PSFFQ) and a meal pattern-based questionnaire (MPQ) in a multi-ethnic population of low socio-economic status (SES).
  
  
  METHODS
  Participants completed six 24-hour dietary recalls (24HR) over six months; the FFQ, PSFFQ and MPQ were completed in random order in the subsequent month. Instruments were interviewer-administered. The PSFFQ and MPQ were developed in formative research concerning difficulties for older adults in responding to standard food-frequency instruments.
  
  
  METHODS
  Rural North Carolina, USA. Subjects One hundred and twenty-two African American, Native American and white adults aged > or = 65 years, with approximately one-third in each ethnic group. Inclusion criteria included education < or = 12 years and income < or = 150% of national poverty level or Medicaid recipient.
  
  
  RESULTS
  Comparing median intakes from the average of the 24HR with the three diet assessment instruments, the MPQ tended to overestimate intakes compared with the FFQ and PSFFQ. Correlations among nutrients obtained by the 24HR and the other three instruments were generally statistically significant and positive. Across nutrients, the PSFFQ was most highly correlated with the 24HR for women, while the FFQ was most highly correlated with the 24HR for men.
  
  
  CONCLUSIONS
  Dietary assessments using 24HR and FFQ were similar to results reported elsewhere, although correlations between 24HR and FFQ were somewhat lower. Interviewer-administered dietary assessments should be used with caution to evaluate dietary intake among older adults with low SES. Gender differences and the lower correlations should be investigated more thoroughly to assist in choosing dietary assessment instruments for this population.
authors.affiliation: Division of Public Health Sciences, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157-1063, USA. squandt@wfubmc.edu
authors.forename: Sara A
authors.initials: SA
authors.lastname: Quandt
authors.forename: Mara Z
authors.initials: MZ
authors.lastname: Vitolins
authors.forename: Shannon L
authors.initials: SL
authors.lastname: Smith
authors.forename: Janet A
authors.initials: JA
authors.lastname: Tooze
authors.forename: Ronny A
authors.initials: RA
authors.lastname: Bell
authors.forename: Cralen C
authors.initials: CC
authors.lastname: Davis
authors.forename: Robert F
authors.initials: RF
authors.lastname: DeVellis
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Arcury
mesh_terms: D001741:Black or African American; D000368:Aged; D004034:Diet Surveys; D005260:Female; D015577:Geriatric Assessment / Q000379:methods; D006801:Humans; D007198:Indians, North American; D007407:Interviews as Topic; D008297:Male; D011939:Mental Recall; D009657:North Carolina; D015596:Nutrition Assessment; D012424:Rural Population; D012923:Social Class; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires / Q000592:standards*; D044465:White People