title: Development and Validation of a Disease-Specific Questionnaire to Assess Patient-Reported Symptoms in Polycystic Liver Disease.
abstract: Treatment of polycystic liver disease (PLD) focuses on symptom improvement. Generic questionnaires lack sensitivity to capture PLD-related symptoms, a prerequisite to determine effectiveness of therapy. We developed and validated a disease-specific questionnaire that assesses symptoms in PLD (PLD-Q). We identified 16 PLD-related symptoms (total score 0-100 points) by literature review and interviews with patients and clinicians. The developed PLD-Q was validated in Dutch (n = 200) and United States (US; n = 203) PLD patients. We assessed the correlation of PLD-Q total score with European Organization for Research and Treatment of Cancer (EORTC) symptom scale, global health visual analogue scale (VAS) of EQ-5D, and liver volume. To test discriminative validity, we compared PLD-Q total scores of patients with different PLD severity stages (Gigot classification) and PLD-Q total scores of PLD patients with general controls and polycystic kidney disease patients without PLD. Reproducibility was tested by comparing original test scores with 2-week retest scores. In total, 167 Dutch and 124 US patients returned the questionnaire. Correlation between PLD-Q total score and EORTC symptom scale (The Netherlands [NL], r = 0.788; US, r = 0.811) and global health VAS (NL, r = -0.517; US, r = -0.593) was good. There was no correlation of PLD-Q total score with liver volume (NL, r = 0.138; P = 0.236; US, r = 0.254; P = 0.052). Gigot type III individuals scored numerically higher than type II patients (NL, 46 vs. 40; P = 0.089; US, 48 vs. 36; P = 0.055). PLD patients scored higher on the PLD-Q total score than general controls (NL, 42 vs. 17; US, 40 vs. 13 points) and polycystic kidney disease patients without PLD (22 points). Reproducibility of PLD-Q was excellent (NL, r = 0.94; US, 0.96).
  
  
  
  PLD-Q is a valid, reproducible, and sensitive disease-specific questionnaire that can be used to assess PLD-related symptoms in clinical care and future research. (Hepatology 2016;64:151-160).
authors.affiliation: Department of Gastroenterology and Hepatology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
authors.forename: Myrte K
authors.initials: MK
authors.lastname: Neijenhuis
authors.affiliation: Department of Gastroenterology and Hepatology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
authors.forename: Tom J G
authors.initials: TJ
authors.lastname: Gevers
authors.affiliation: Division of Nephrology and Hypertension, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota.
authors.forename: Marie C
authors.initials: MC
authors.lastname: Hogan
authors.affiliation: Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota.
authors.forename: Patrick S
authors.initials: PS
authors.lastname: Kamath
authors.affiliation: Department of Gastroenterology and Hepatology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
authors.forename: Titus F M
authors.initials: TF
authors.lastname: Wijnands
authors.affiliation: Department of Gastroenterology and Hepatology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
authors.forename: Ralf C P M
authors.initials: RC
authors.lastname: van den Ouweland
authors.affiliation: Division of Nephrology and Hypertension, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota.
authors.forename: Marie E
authors.initials: ME
authors.lastname: Edwards
authors.affiliation: Quality of Life Group, Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota.
authors.forename: Jeff A
authors.initials: JA
authors.lastname: Sloan
authors.affiliation: Radboud Institute for Health Sciences, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
authors.forename: Wietske
authors.initials: W
authors.lastname: Kievit
authors.affiliation: Department of Gastroenterology and Hepatology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
authors.forename: Joost P H
authors.initials: JP
authors.lastname: Drenth
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003560:Cysts; D005260:Female; D006801:Humans; D007668:Kidney / Q000473:pathology; D008099:Liver / Q000473:pathology; D008107:Liver Diseases; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D011446:Prospective Studies; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D055815:Young Adult