title: Validity of the Neurology Quality-of-Life (Neuro-QoL) measurement system in adult epilepsy.
abstract: Epilepsy is a chronic neurological disorder that results in recurring seizures and can have a significant adverse effect on health-related quality of life (HRQL). The Neuro-QoL measurement initiative is an NINDS-funded system of patient-reported outcome measures for neurology clinical research, which was designed to provide a precise and standardized way to measure HRQL in epilepsy and other neurological disorders. Using mixed-method and item response theory-based approaches, we developed generic item banks and targeted scales for adults and children with major neurological disorders. This paper provides empirical results from a clinical validation study with a sample of adults diagnosed with epilepsy. One hundred twenty-one people diagnosed with epilepsy participated, the majority of which were male (62%) and Caucasian (95%), with a mean age of 47.3 (SD=16.9). Baseline assessments included Neuro-QoL short forms and general and external validity measures. The Neuro-QoL short forms that are not typically found in other epilepsy-specific HRQL instruments include Stigma, Sleep Disturbance, Emotional and Behavioral Dyscontrol, and Positive Affect and Well-Being. Neurology Quality-of-Life short forms demonstrated adequate reliability (internal consistency range=.86-.96; test-retest range=.57-.89). Pearson correlations (p<.01) between Neuro-QoL forms of emotional distress (anxiety, depression, stigma) and the QOLIE-31 Emotional Well-Being subscale were in the moderate-to-strong range (r's=.66, .71 and .53, respectively), as were relations with the PROMIS Global Mental Health subscale (r's=.59, .74 and .52, respectively). Moderate correlations were observed between Neuro-QoL Social Role Performance and Satisfaction and the QOLIE-31 Social Function (r's=.58 and .52, respectively). In measuring aspects of physical function, the Neuro-QoL Mobility and Upper Extremity forms demonstrated moderate associations with the PROMIS Global Physical Function subscale (r's=.60 and .61, respectively). Neuro-QoL measures of perceived cognitive function (executive function and general concerns) produced moderate-to-strong correlations with the QOLIE-31 Cognition subscale (r's=.65 and .75, respectively) and moderate relations with the Liverpool Adverse Events Profile (r's=.51 and .69, respectively). Finally, the Neuro-QoL Fatigue measure demonstrated moderate associations with the QOLIE-31 Energy/Fatigue subscale (r=-.65), Liverpool Adverse Events Profile (r=.69), and the Liverpool Seizure Severity Scale (r=.50). Five Neuro-QoL short forms demonstrated statistically significant responsiveness to change at 5-7months, including Fatigue, Sleep Disturbance, Depression, Positive Affect and Well-Being, and Emotional and Behavioral Dyscontrol. Overall, Neuro-QoL instruments showed good evidence for internal consistency, test-retest reliability, convergent validity, and responsiveness to change over several months. These results support the validity of Neuro-QoL to measure HRQL in adults with epilepsy.
authors.affiliation: Department of Medical Social Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, USA. Electronic address: d-victorson@northwestern.edu.
authors.forename: David
authors.initials: D
authors.lastname: Victorson
authors.affiliation: Department of Neurology, University of Texas Health Science Center, San Antonio, TX, USA. Electronic address: CAVAZOSJ@uthscsa.edu.
authors.forename: Jose E
authors.initials: JE
authors.lastname: Cavazos
authors.affiliation: Department of Neurological Sciences, University of Vermont College of Medicine, Burlington, VT, USA. Electronic address: gregory.holmes@uvm.edu.
authors.forename: Gregory L
authors.initials: GL
authors.lastname: Holmes
authors.affiliation: Department of Neurology, University of Chicago, Chicago, IL, USA. Electronic address: areder@neurology.bsd.uchicago.edu.
authors.forename: Anthony T
authors.initials: AT
authors.lastname: Reder
authors.affiliation: Division of Neurology, Department of Internal Medicine, University of Puerto Rico, Medical Sciences Campus, San Juan, PR, USA. Electronic address: valerie.wojna1@upr.edu.
authors.forename: Valerie
authors.initials: V
authors.lastname: Wojna
authors.affiliation: Department of Medical Social Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, USA. Electronic address: c-nowinski@northwestern.edu.
authors.forename: Cindy
authors.initials: C
authors.lastname: Nowinski
authors.affiliation: Mellen Center, Cleveland Clinic Foundation, Cleveland, OH, USA. Electronic address: MillerD@ccf.org.
authors.forename: Deborah
authors.initials: D
authors.lastname: Miller
authors.affiliation: Department of Medical Social Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, USA. Electronic address: sarah-buono@northwestern.edu.
authors.forename: Sarah
authors.initials: S
authors.lastname: Buono
authors.affiliation: Department of Medical Social Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, USA. Electronic address: amuelle4@uic.edu.
authors.forename: Allison
authors.initials: A
authors.lastname: Mueller
authors.affiliation: National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA. Electronic address: MoyC@ninds.nih.gov.
authors.forename: Claudia
authors.initials: C
authors.lastname: Moy
authors.affiliation: Department of Medical Social Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, USA. Electronic address: d-cella@northwestern.edu.
authors.forename: David
authors.initials: D
authors.lastname: Cella
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001526:Behavioral Symptoms / Q000209:etiology*; D035843:Biomedical Research; D004827:Epilepsy / Q000150:complications* / Q000175:diagnosis / Q000523:psychology*; D005221:Fatigue / Q000175:diagnosis / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009462:Neurology; D011788:Quality of Life; D015203:Reproducibility of Results; D055815:Young Adult
keywords: Epilepsy; Measurement; Neuro-QoL; Psychometrics; Quality of life; Validation