title: The Comparative Frame of Reference in Self-Rated Health Questions Matters When Predicting Difficulty with Activities of Daily Living.
abstract: BACKGROUND
  Within the assessment of frailty, self-rated health (SRH) questions remain frequently used in survey research attempting to quantify a subjective and global measure of health. Studies have largely ignored the fact that SRH questions may differ in their ability to predict level of difficulty with performing activities of daily living (ADLs)-a variance partially influenced by whether a comparative frame of reference in used in the SRH question.
  
  
  OBJECTIVE
  Investigate if a Comparative-SRH (C-SRH) question with response options ranging on an adjectival scale ranging from 0 to 3; and a Non-Comparative-SRH (NC-SRH) question with an adjectival response scale from range 0 to 5; differ in their ability to predict level of difficulty in performing ADLs after accounting for demographic, psychosocial, and related health factors.
  
  
  METHODS
  Cross-sectional study of community-dwelling adults (n=275; x age=68; female=54%; x BMI=31) from North Carolina participating in the Hispanic Aging Survey (HAS) were used in multivariable linear regressions to predict a granular measure of level of difficulty performing ADLs.
  
  
  RESULTS
  Only C-SRH has a statistically significant relationship with ADLs-where each increase in C-SRH (i.e., more positively self-rated health) is associated with a decrease in ADL level of difficult.
  
  
  CONCLUSIONS
  Using a comparative frame of reference in SRH questions may have important implications when attempting to understand the statistical relationship between self-rated global health and physical function in the assessment of frailty in older adults.
authors.affiliation: C Siordia, PhD, 130 North Bellefield Ave, Pittsburgh, PA 15213, cas271@pitt.edu.
authors.forename: C
authors.initials: C
authors.lastname: Siordia
authors.forename: H T
authors.initials: HT
authors.lastname: Nguyen