title: Assessment of Breathlessness in Lung Cancer: Psychometric Properties of the Dyspnea-12 Questionnaire.
abstract: The Dyspnea-12 (D-12) Questionnaire is a well-validated instrument in respiratory illnesses for breathlessness assessment, but its psychometric properties have not been tested in lung cancer.
  
  
  
  To demonstrate the psychometric properties of the D-12 in lung cancer patients.
  
  
  
  Baseline data from a lung cancer feasibility trial were adopted for this analysis. D-12 and a series of patient-reported tools, including five Numeric Rating Scales (NRS), the Hospital Anxiety and Depression Scale (HADS), and the Lung Cancer Symptom Scale (LCSS), were used for the psychometric assessment. Spearman's correlation coefficients (rs) were used to estimate the convergent validity of the D-12 with the NRS, HADS, and LCSS. Exploratory factor analysis was performed to examine construct validity. Reliability was tested by Cronbach's alpha and item-to-total correlations. D-12 score difference between patients with or without anxiety, depression, and chronic obstructive pulmonary disease (COPD) was explored to identify its discriminate performance.
  
  
  
  One hundred and one lung cancer patients were included. There were significantly positive correlations between the D-12 and the HADS, LCSS, and NRS measuring breathlessness severity and its associated affective distress. Factor analysis clearly identified two components (physical and emotional) of the D-12. Cronbach's alpha for D-12 total, physical, and emotional subscales was 0.95, 0.92, and 0.94, respectively. Patients with anxiety or depression demonstrated significantly higher D-12 scores than those without it, and patients with COPD reported significantly more severe breathlessness than those without COPD.
  
  
  
  The D-12 is a valid and reliable self-reported questionnaire for use in breathlessness assessment in lung cancer patients.
authors.affiliation: School of Nursing, Midwifery and Social Work, University of Manchester, Manchester, United Kingdom; School of Nursing, The Hong Kong Polytechnic University, Kowloon, Hong Kong.
authors.forename: Jing-Yu
authors.initials: JY
authors.lastname: Tan
authors.affiliation: School of Nursing, Midwifery and Social Work, University of Manchester, Manchester, United Kingdom; The Christie NHS Foundation Trust, Manchester, United Kingdom. Electronic address: janelle.yorke@manchester.ac.uk.
authors.forename: Janelle
authors.initials: J
authors.lastname: Yorke
authors.affiliation: The Christie NHS Foundation Trust, Manchester, United Kingdom.
authors.forename: Amelie
authors.initials: A
authors.lastname: Harle
authors.affiliation: Centre for Respiratory and Allergy, University Hospital South Manchester, Manchester, United Kingdom; Faculty of Medicine and Human Sciences, University of Manchester, Manchester, United Kingdom.
authors.forename: Jacky
authors.initials: J
authors.lastname: Smith
authors.affiliation: The Christie NHS Foundation Trust, Manchester, United Kingdom; Faculty of Medicine and Human Sciences, University of Manchester, Manchester, United Kingdom.
authors.forename: Fiona
authors.initials: F
authors.lastname: Blackhall
authors.affiliation: School of Nursing, Midwifery and Social Work, University of Manchester, Manchester, United Kingdom.
authors.forename: Mark
authors.initials: M
authors.lastname: Pilling
authors.affiliation: School of Nursing, Midwifery and Social Work, University of Manchester, Manchester, United Kingdom; School of Nursing, The Hong Kong Polytechnic University, Kowloon, Hong Kong.
authors.forename: Alex
authors.initials: A
authors.lastname: Molassiotis
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001007:Anxiety / Q000150:complications / Q000503:physiopathology; D003863:Depression / Q000150:complications / Q000503:physiopathology; D004417:Dyspnea / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000150:complications* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011594:Psychometrics; D011788:Quality of Life; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: Breathlessness; lung cancer; psychometrics; reliability; scale; validity