title: Exploring household income as a predictor of psychological well-being among long-term colorectal cancer survivors.
abstract: OBJECTIVE
  The purpose of this analysis was to determine the unique contribution of household income to the variance explained in psychological well-being (PWB) among a sample of colorectal cancer (CRC) survivors.
  
  
  METHODS
  This study is a secondary analysis of data collected as part of the Health-Related Quality of Life in Long-Term Colorectal Cancer Survivors Study, which included CRC survivors with (cases) and without (controls) ostomies. The dataset included socio-demographic, health status, and health-related quality of life (HRQOL) information. HRQOL was assessed with the modified City of Hope Quality of Life (mCOH-QOL)-Ostomy questionnaire and SF-36v2. To assess the relationship between income and PWB, a hierarchical linear regression model was constructed combining data from both cases and controls.
  
  
  RESULTS
  After accounting for the proportion of variance in PWB explained by the other independent variables in the model, the additional variance explained by income was significant (R (2) increased from 0.228 to 0.250; P = 0.006).
  
  
  CONCLUSIONS
  Although the study design does not allow causal inference, these results demonstrate a significant relationship between income and PWB in CRC survivors. The findings suggest that for non-randomized group comparisons of HRQOL, income should, at the very least, be included as a control variable in the analysis.
authors.affiliation: College of Pharmacy, University of Arizona, P.O. Box 210202, Tucson, AZ, 85721-0202, USA. lundy@pharmacy.arizona.edu
authors.forename: J Jason
authors.initials: JJ
authors.lastname: Lundy
authors.forename: Stephen Joel
authors.initials: SJ
authors.lastname: Coons
authors.forename: Christopher
authors.initials: C
authors.lastname: Wendel
authors.forename: Mark C
authors.initials: MC
authors.lastname: Hornbrook
authors.forename: Lisa
authors.initials: L
authors.lastname: Herrinton
authors.forename: Marcia
authors.initials: M
authors.lastname: Grant
authors.forename: Robert S
authors.initials: RS
authors.lastname: Krouse
mesh_terms: D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000191:economics* / Q000523:psychology*; D003430:Cross-Sectional Studies; D003627:Data Interpretation, Statistical; D006801:Humans; D007182:Income; D015233:Models, Statistical; D011788:Quality of Life; D017741:Survivors / Q000523:psychology*