title: Measuring the impact and distress of health problems from the individual's perspective: development of the Perceived Impact of Problem Profile (PIPP).
abstract: BACKGROUND
  The aim of this study was to develop and conduct preliminary validation of the Perceived Impact of Problem Profile (PIPP). Based on the biopsychosocial model of health and functioning, the PIPP was intended as a generic research and clinical measurement tool to assess the impact and distress of health conditions from the individuals' perspective. The ICF classification system was used to guide the structure of the PIPP with subscales included to assess impact on self-care, mobility, participation, relationships and psychological well-being. While the ICF focuses on the classification of objective health and health related status, the PIPP broadens this focus to address the individuals' subjective experience of their health condition.
  
  
  METHODS
  An item pool of 23 items assessing both impact and distress on five key domains was generated. These were administered to 169 adults with mobility impairment. Rasch analysis using RUMM2020 was conducted to assess the psychometric properties of each set of items. Preliminary construct validation of the PIPP was performed using the EQ5D.
  
  
  RESULTS
  For both the Impact and Distress scales of the PIPP, the five subscales (Self-care, Mobility, Participation, Relationships, and Psychological Well-being) showed adequate psychometric properties, demonstrating fit to the Rasch model. All subscales showed adequate person separation reliability and no evidence of differential item functioning for sex, age, educational level or rural vs urban residence. Preliminary validity testing using the EQ5D items provided support for the subscales.
  
  
  CONCLUSIONS
  This preliminary study, using a sample of adults with mobility impairment, provides support for the psychometric properties of the PIPP as a potential clinical and research measurement tool. The PIPP provides a brief, but comprehensive means to assess the key ICF components, focusing on the individuals' perspective of the impact and distress caused by their health condition. Further validation of its use across different health conditions and varying cultural settings is required.
authors.affiliation: Faculty of Life and Social Sciences, Swinburne University of Technology, P,O, Box 218, Hawthorn, Victoria 3122, Australia. jpallant@swin.edu.au
authors.forename: Julie F
authors.initials: JF
authors.lastname: Pallant
authors.forename: RoseAnne
authors.initials: R
authors.lastname: Misajon
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Bennett
authors.forename: Lenore
authors.initials: L
authors.lastname: Manderson
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D016000:Cluster Analysis; D017281:Cost of Illness; D006233:Persons with Disabilities / Q000523:psychology*; D005260:Female; D006801:Humans; D007398:Interpersonal Relations; D008297:Male; D010147:Pain Measurement; D011594:Psychometrics / Q000295:instrumentation*; D011788:Quality of Life / Q000523:psychology*; D012648:Self Care / Q000523:psychology*; D018434:Sickness Impact Profile; D011795:Surveys and Questionnaires; D014739:Victoria