title: Development and testing of a short form of the patient activation measure.
abstract: OBJECTIVE
  The Patient Activation Measure (PAM) is a 22-item measure that assesses patient knowledge, skill, and confidence for self-management. The measure was developed using Rasch analyses and is an interval level, unidimensional, Guttman-like measure. The current analysis is aimed at reducing the number of items in the measure while maintaining adequate precision.
  
  
  METHODS
  We relied on an iterative use of Rasch analysis to identify items that could be eliminated without loss of significant precision and reliability. With each item deletion, the item scale locations were recalibrated and the person reliability evaluated to check if and how much of a decline in precision of measurement resulted from the deletion of the item.
  
  
  METHODS
  The data used in the analysis were the same data used in the development of the original 22-item measure. These data were collected in 2003 via a telephone survey of 1,515 randomly selected adults. Principal Findings. The analysis yielded a 13-item measure that has psychometric properties similar to the original 22-item version. The scores for the 13-item measure range in value from 38.6 to 53.0 (on a theoretical 0-100 point scale). The range of values is essentially unchanged from the original 22-item version. Subgroup analysis suggests that there is a slight loss of precision with some subgroups.
  
  
  CONCLUSIONS
  The results of the analysis indicate that the shortened 13-item version is both reliable and valid.
authors.affiliation: Department of Planning, Publicy, & Management, University of Oregon, Eugene, 97403, USA.
authors.forename: Judith H
authors.initials: JH
authors.lastname: Hibbard
authors.forename: Eldon R
authors.initials: ER
authors.lastname: Mahoney
authors.forename: Jean
authors.initials: J
authors.lastname: Stockard
authors.forename: Martin
authors.initials: M
authors.lastname: Tusler
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002908:Chronic Disease; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008297:Male; D008875:Middle Aged; D010358:Patient Participation; D010361:Patients; D012648:Self Care / Q000592:standards*; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires