title: The psychosocial impact of cancer: evidence in support of independent general positive and negative components.
abstract: OBJECTIVE
  Considerable research has demonstrated the negative psychosocial impact of cancer. Recent work has highlighted positive psychosocial outcomes. Research is now needed to evaluate the relationship between negative and positive impacts. This paper reports the development and validation of a measurement model capturing positive and negative psychosocial illness impacts.
  
  
  METHODS
  The sample included 754 cancer patients on- or post-treatment. Item development was informed by literature review, expert input patient interviews and the results of a pilot study of 205 cancer patients, resulting in 43 positive and 46 negative items. Factor analyses were used to evaluate the dimensionality of the item pools. Analysis of variance (ANOVA) was used to examine relationships between psychosocial illness impact and other variables.
  
  
  RESULTS
  Unidimensionality was demonstrated within but not across negative and positive impact items. ANOVA results showed differential relationships between negative and positive impacts, respectively, and patient sociodemographic and clinical variables.
  
  
  CONCLUSIONS
  Positive and negative psychosocial illness impacts are best conceptualized and measured as two independent factors. Computerized adaptive tests and short-form measures developed from this comprehensive psychosocial illness impact item bank may benefit future research and clinical applications.
authors.affiliation: Department of Medical Social Sciences, Feinberg School of Medicine at Northwestern University, 710 North Lake Shore drive, #729, Chicago, IL 60611, USA. js-lai@northwestern.edu
authors.forename: Jin-Shei
authors.initials: JS
authors.lastname: Lai
authors.forename: Sofia F
authors.initials: SF
authors.lastname: Garcia
authors.forename: John M
authors.initials: JM
authors.lastname: Salsman
authors.forename: Sarah
authors.initials: S
authors.lastname: Rosenbloom
authors.forename: David
authors.initials: D
authors.lastname: Cella
mesh_terms: D000704:Analysis of Variance; D017281:Cost of Illness; D005260:Female; D006801:Humans; D007407:Interviews as Topic; D008297:Male; D009369:Neoplasms / Q000523:psychology*; D010865:Pilot Projects; D015203:Reproducibility of Results; D013315:Stress, Psychological