title: Interview-based versus questionnaire-based quality of life outcomes before and after prostatectomy.
abstract: BACKGROUND
  Functional outcome and quality of life (QOL) domains are important outcomes after curative therapy for prostate cancer. Although useful for scientific purposes, QOL questionnaires may be too extensive for daily routine, and single questions or interview-assessed outcomes may be more practical alternatives. The QOL outcomes of these measures were compared.
  
  
  METHODS
  The QOL of patients undergoing Robot-Assisted Radical Prostatectomy (RARP) in our hospital was monitored before and after treatment using both brief standardized interview questions, as well as more extensive validated questionnaires. The interview questions address erectile function and urinary continence with only one question on each subject (both four response items). Questionnaires included a total of 74 questions (EORTC-QLQ-C30, EORTC-QLQ-PR25, international index of erectile function-15, and international consultation on incontinence questionnaire-short form).
  
  
  RESULTS
  In 925 RARP patients, pre- and postoperative interview and questionnaire QOL data were available with a median follow up of 20 months. Improvement in both erectile function and continence scores occurred up till 2 years after the RARP for both interview- and questionnaire-based evaluations. On an individual patient basis, interview scores poorly correlated with questionnaire-based domains for continence and erectile function. Single questions from the questionnaire showed better correlation with domain scores. Functional recovery of continence after 1 year was worse when assessed by questionnaire than by interview evaluation. A decrease in physical (8%) and overall QOL (12%) after prostatectomy as assessed by the EORTC-QLQ-C30 questionnaire was better predicted by questionnaire-based than interview-based scores. Continence scores had a greater impact on physical and overall QOL scores than on erectile function scores.
  
  
  CONCLUSIONS
  Interview/assessed continence and erectile function outcome after RARP showed limited association with questionnaire-based evaluation and may overestimate functional recovery. Continence scores for both interviews and questionnaires were stronger correlated with physical and overall QOL than erectile function scores.
authors.affiliation: Department of Urology, Netherlands Cancer Institute , Amsterdam, The Netherlands .
authors.forename: Henk G
authors.initials: HG
authors.lastname: van der Poel
authors.forename: Corinne
authors.initials: C
authors.lastname: Tillier
authors.forename: Willem M
authors.initials: WM
authors.lastname: de Blok
authors.forename: Cenk
authors.initials: C
authors.lastname: Acar
authors.forename: Erik H A M
authors.initials: EH
authors.lastname: van Muilekom
authors.forename: Roderick C N
authors.initials: RC
authors.lastname: van den Bergh
mesh_terms: D000328:Adult; D000368:Aged; D006801:Humans; D007406:Interview, Psychological / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011468:Prostatectomy / Q000379:methods*; D011471:Prostatic Neoplasms / Q000503:physiopathology / Q000523:psychology / Q000601:surgery*; D011788:Quality of Life; D020127:Recovery of Function; D012371:Robotics / Q000379:methods; D011795:Surveys and Questionnaires; D014563:Urodynamics / Q000502:physiology