title: Self-reported health parameters compared with clinician measurements: methods in practice-based research.
abstract: BACKGROUND
  Self-reported health data are used by health insurance companies to assess risk. Most studies show underreporting compared with clinical measurements.
  
  
  OBJECTIVE
  To compare self-reported height, weight, blood pressure, waist circumference, and dietary intake with registered dietitian's (RD's) measures of the same parameters.
  
  
  METHODS
  This is a secondary analysis of data collected in a larger study on the benefits of Medical Nutrition Therapy from an RD for overweight and obese patients when provided free of charge through an insurance benefit.
  
  
  METHODS
  Participants completed a health risk assessment survey at home, from which the self-reported measures were extracted. The clinical measurements were taken by an RD in the office during a visit for Medical Nutrition Therapy.
  
  
  METHODS
  Participants were 81.4% female, with a mean body mass index of 35.0. All were insured and had a least 1 visit with an RD.
  
  
  METHODS
  Main outcomes were correlation between self-reported and RD-measured height, weight, body mass index, blood pressure, and waist circumference. Blood pressure was categorized as normal or high and the κ statistic was used to examine category agreement between the 2 measures. Servings of food groups were compared between the 2 measures by examining cumulative percent within 0, 1, or 2 servings of the RD-measured value.
  
  
  RESULTS
  The 2 measures of height and weight were highly correlated (0.974 and 0.986, respectively). Blood pressure was more weakly correlated and when categorized had low κ scores, as did servings of food groups.
  
  
  CONCLUSIONS
  Height and weight were more closely correlated than in previous studies. In an insured population enrolled in a weight management program, self-reported measures may be accurate for determining program impact. Blood pressure may be better collected categorically than continuously. The necessity of food intake assessment on a risk assessment should be reconsidered.
authors.affiliation: Community Health Division of the Community and Family Medicine Department, Duke Medical School, Duke University, Durham, North Carolina (Dr Murphy); Community and Behavioral Health, and Epidemiology, College of Public Health, University of Iowa, Iowa City, Iowa (Dr Snetselaar); Academy of Nutrition and Dietetics, Chicago, Illinois (Dr Myers); Healthcare Program Development, BlueCross BlueShield of North Carolina, Durham, North Carolina (Ms LaForge); BlueCross BlueShield of North Carolina, Durham, North Carolina (Ms Qualls and Dr Blackwelder); Dietetics Practice Based Research Network, Academy of Nutrition and Dietetics, Chicago, Illinois (Ms Hand); and BlueCross BlueShield of North Carolina, Durham, North Carolina (Dr Bradley). Ms Qualls is now with Duke Clinical Research Institute, Durham, North Carolina, and Dr Blackwelder is now with Cornerstone Health Enablement Strategic Services, High Point, North Carolina.
authors.forename: Gwendolyn
authors.initials: G
authors.lastname: Murphy
authors.forename: Linda
authors.initials: L
authors.lastname: Snetselaar
authors.forename: Esther
authors.initials: E
authors.lastname: Myers
authors.forename: Betsy
authors.initials: B
authors.lastname: LaForge
authors.forename: Laura G
authors.initials: LG
authors.lastname: Qualls
authors.forename: Rosa K
authors.initials: RK
authors.lastname: Hand
authors.forename: Stephen
authors.initials: S
authors.lastname: Blackwelder
authors.forename: Don
authors.initials: D
authors.lastname: Bradley
mesh_terms: D000328:Adult; D001794:Blood Pressure; D001827:Body Height; D015992:Body Mass Index; D001835:Body Weight; D003430:Cross-Sectional Studies; D002149:Energy Intake; D005260:Female; D006305:Health Status Indicators; D006801:Humans; D008297:Male; D008875:Middle Aged; D009657:North Carolina; D064686:Nutritionists; D009765:Obesity / Q000453:epidemiology / Q000517:prevention & control*; D050177:Overweight / Q000453:epidemiology / Q000517:prevention & control*; D018570:Risk Assessment; D057566:Self Report; D011795:Surveys and Questionnaires; D055105:Waist Circumference