title: The Xerostomia Inventory: a multi-item approach to measuring dry mouth.
abstract: OBJECTIVE
  To develop a valid multi-item method of measuring the symptoms of xerostomia which includes the wide range of xerostomia symptoms in a single quantitative measure.
  
  
  METHODS
  A combination of qualitative and quantitative approaches.
  
  
  METHODS
  A cohort study in South Australia.
  
  
  METHODS
  Older people aged 65 years or more who were taking part in the South Australian Dental Longitudinal Study.
  
  
  METHODS
  Xerostomia symptoms were evaluated using a multi-item inventory format and, for comparison purposes, a standard single dry-mouth question. Resting whole-salivary flow rate was estimated using the 'spit' method.
  
  
  RESULTS
  Xerostomia and flow-rate data were available for 636 individuals. Factor analysis revealed the presence of a discrete xerostomia dimension, represented by 11 items whose responses were summated to give a single Xerostomia Inventory (XI) scale score. This had a very low correlation with resting flow rate but a much stronger, positive correlation with the standard dry-mouth question responses.
  
  
  CONCLUSIONS
  The XI shows adequate content and concurrent validity, and appears to be a promising advance on previous approaches to xerostomia symptomatology although further testing is required.
authors.affiliation: Department of Oral Health, University of Otago, Dunedin, New Zealand.
authors.forename: W M
authors.initials: WM
authors.lastname: Thomson
authors.forename: J M
authors.initials: JM
authors.lastname: Chalmers
authors.forename: A J
authors.initials: AJ
authors.lastname: Spencer
authors.forename: S M
authors.initials: SM
authors.lastname: Williams
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D005260:Female; D006801:Humans; D016013:Likelihood Functions; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012463:Saliva / Q000737:chemistry; D012720:Severity of Illness Index; D013021:South Australia; D011795:Surveys and Questionnaires; D014987:Xerostomia / Q000175:diagnosis*