title: Self-reported sitting time in New York City adults, the Physical Activity and Transit Survey, 2010-2011.
abstract: BACKGROUND
  Recent studies have demonstrated the negative health consequences associated with extended sitting time, including metabolic disturbances and decreased life expectancy. The objectives of this study were to characterize sitting time in an urban adult population and assess the validity of a 2-question method of self-reported sitting time.
  
  
  METHODS
  The New York City Health Department conducted the 2010-2011 Physical Activity and Transit Survey (N = 3,597); a subset of participants wore accelerometers for 1 week (n = 667). Self-reported sitting time was assessed from 2 questions on time spent sitting (daytime and evening hours). Sedentary time was defined as accelerometer minutes with less than 100 counts on valid days. Descriptive statistics were used to estimate the prevalence of sitting time by demographic characteristics. Validity of sitting time with accelerometer-measured sedentary time was assessed using Spearman's correlation and Bland-Altman techniques. All data were weighted to be representative of the New York City adult population based on the 2006-2008 American Community Survey.
  
  
  RESULTS
  Mean daily self-reported sitting time was 423 minutes; mean accelerometer-measured sedentary time was 490 minutes per day (r = 0.32, P < .001). The mean difference was 49 minutes per day (limits of agreement: -441 to 343). Sitting time was higher in respondents at lower poverty and higher education levels and lower in Hispanics and people who were foreign-born.
  
  
  CONCLUSIONS
  Participants of higher socioeconomic status, who are not typically the focus of health disparities-related research, had the highest sitting times; Hispanics had the lowest levels. Sitting time may be accurately assessed by self-report with the 2-question method for population surveillance but may be limited in accurately characterizing individual-level behavior.
authors.affiliation: New York University School of Medicine, Department of Population Health, 550 First Ave, VZN Suite No. 844, 8th Floor, New York, NY 10016. Email: stella.yi@nyumc.org.
authors.forename: Stella S
authors.initials: SS
authors.lastname: Yi
authors.affiliation: New York City Department of Health and Mental Hygiene, New York, New York.
authors.forename: Katherine F
authors.initials: KF
authors.lastname: Bartley
authors.affiliation: New York City Department of Health and Mental Hygiene, New York, New York.
authors.forename: Melanie J
authors.initials: MJ
authors.lastname: Firestone
authors.affiliation: New York City Department of Health and Mental Hygiene, New York, New York.
authors.forename: Karen K
authors.initials: KK
authors.lastname: Lee
authors.affiliation: New York City Department of Health and Mental Hygiene, New York, New York.
authors.forename: Donna L
authors.initials: DL
authors.lastname: Eisenhower
mesh_terms: D061725:Accelerometry; D000293:Adolescent; D000328:Adult; D000368:Aged; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D005006:Ethnicity / Q000523:psychology / Q000706:statistics & numerical data; D005260:Female; D005500:Follow-Up Studies; D015438:Health Behavior; D006801:Humans; D016014:Linear Models; D008297:Male; D011939:Mental Recall; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D015999:Multivariate Analysis; D009519:New York City / Q000453:epidemiology; D009749:Nutrition Surveys; D004856:Postural Balance / Q000502:physiology*; D011203:Poverty / Q000523:psychology / Q000706:statistics & numerical data; D015203:Reproducibility of Results; D057185:Sedentary Behavior / Q000208:ethnology; D057566:Self Report; D012923:Social Class; D011795:Surveys and Questionnaires / Q000592:standards; D013997:Time Factors; D014505:Urban Population / Q000706:statistics & numerical data*; D016138:Walking / Q000502:physiology / Q000523:psychology* / Q000706:statistics & numerical data; D055815:Young Adult