title: Classification of painful bone metastases as mild, moderate, or severe using both EORTC QLQ-C15-PAL and EORTC QLQ-BM22.
abstract: Previous studies have determined optimal cut points (CPs) for the classification of pain severity as mild, moderate, or severe using only the Brief Pain Inventory (BPI) or the BPI in conjunction with a quality of life (QOL) tool. The purpose of our study was to determine the optimal CPs based on correlation with only QOL outcomes.
  
  
  
  We conducted an analysis of 298 patients treated with radiation therapy for painful bone metastases on a phase III randomized trial. Prior to treatment, patients provided their worst pain score on a scale of 0 (no pain) to 10 (worst possible pain), as well as completed the European Organization of Cancer Research and Treatment (EORTC) QOL Questionnaire Bone Metastases module (QLQ-BM22) and the EORTC QOL Questionnaire Core-15 Palliative (QLQ-C15-PAL). Optimal CPs were determined to be those that yielded the largest F ratio for the between category effect on each subscale of the QLQ-BM22 and QLQ-C15-PAL using the multivariate analysis of variance (MANOVA).
  
  
  
  The two largest F ratios for Wilk's λ, Pillai's Trace, and Hotelling's Trace were for CPs 5,6 and 5,7. Combining both, the optimal CPs to differentiate between mild, moderate, and severe pain were 5 and 7. Pain scores of 1-5, 6, and 7-10 were classified as mild, moderate, and severe, respectively. Patients with severe pain experienced greater functional interference and poorer QOL when compared to those with mild pain.
  
  
  
  Our results suggest that, based on the impact of pain on QOL measures, pain scores should be classified as follows: 1-5 as mild pain, 6 as moderate pain, and 7-10 as severe pain. Optimal CPs vary depending on the type of outcome measurement used.
authors.affiliation: Sunnybrook Odette Cancer Centre, University of Toronto, Toronto, ON, Canada.
authors.forename: Rachel
authors.initials: R
authors.lastname: McDonald
authors.affiliation: Canadian Clinical Trials Group, Cancer Research Institute, Queen's University, Kingston, ON, Canada.
authors.forename: Keyue
authors.initials: K
authors.lastname: Ding
authors.affiliation: Sunnybrook Odette Cancer Centre, University of Toronto, Toronto, ON, Canada. Edward.Chow@sunnybrook.ca.
authors.forename: Edward
authors.initials: E
authors.lastname: Chow
authors.affiliation: Juravinski Hospital and Cancer Centre and McMaster University, Hamilton, ON, Canada.
authors.forename: Ralph M
authors.initials: RM
authors.lastname: Meyer
authors.affiliation: Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC, Canada.
authors.forename: Abdenour
authors.initials: A
authors.lastname: Nabid
authors.affiliation: Hopital Maisonneuve-Rosemont, Montreal, QC, Canada.
authors.forename: Pierre
authors.initials: P
authors.lastname: Chabot
authors.affiliation: CHUM-Hopital Notre-Dame, Montreal, QC, Canada.
authors.forename: Genevieve
authors.initials: G
authors.lastname: Coulombe
authors.affiliation: CancerCare Manitoba, Winnipeg, MB, Canada.
authors.forename: Shahida
authors.initials: S
authors.lastname: Ahmed
authors.affiliation: Grand River Regional Cancer Centre, Grand River Hospital, Kitchener, ON, Canada.
authors.forename: Joda
authors.initials: J
authors.lastname: Kuk
authors.affiliation: London Regional Cancer Program, London, ON, Canada.
authors.forename: Rashid
authors.initials: R
authors.lastname: Dar
authors.affiliation: Cancer Centre of Southeastern Ontario, Kingston General Hospital, Kingston, ON, Canada.
authors.forename: Aamer
authors.initials: A
authors.lastname: Mahmud
authors.affiliation: Cross Cancer Institute, Edmonton, AB, Canada.
authors.forename: Alysa
authors.initials: A
authors.lastname: Fairchild
authors.affiliation: Canadian Clinical Trials Group, Cancer Research Institute, Queen's University, Kingston, ON, Canada.
authors.forename: Carolyn F
authors.initials: CF
authors.lastname: Wilson
authors.affiliation: Tom Baker Cancer Centre, University of Calgary, Calgary, AB, Canada.
authors.forename: Jackson S Y
authors.initials: JS
authors.lastname: Wu
authors.affiliation: University of Ottawa, Ottawa Hospital Research Institute, Ottawa, ON, Canada.
authors.forename: Kristopher
authors.initials: K
authors.lastname: Dennis
authors.affiliation: Sunnybrook Odette Cancer Centre, University of Toronto, Toronto, ON, Canada.
authors.forename: Carlo
authors.initials: C
authors.lastname: DeAngelis
authors.affiliation: Princess Margaret Hospital, Radiation Medicine Program, Ontario Cancer Institute, University of Toronto, Toronto, ON, Canada.
authors.forename: Rebecca K S
authors.initials: RK
authors.lastname: Wong
authors.affiliation: Canadian Clinical Trials Group, Cancer Research Institute, Queen's University, Kingston, ON, Canada.
authors.forename: Liting
authors.initials: L
authors.lastname: Zhu
authors.affiliation: Queen's University, Kingston, ON, Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Brundage
mesh_terms: D000368:Aged; D001859:Bone Neoplasms / Q000556:secondary*; D005260:Female; D006801:Humans; D008297:Male; D017063:Outcome Assessment, Health Care; D010147:Pain Measurement / Q000379:methods*; D011788:Quality of Life / Q000523:psychology*; D011795:Surveys and Questionnaires
keywords: Bone metastases; Cut points; Functional interference; Pain severity; Quality of life; Survival