Validation of patient determined disease steps (PDDS) scale scores in persons with multiple sclerosis

Yvonne C Learmonth, Robert W Motl, Brian M Sandroff, John H Pula, Diego Cadavid, Yvonne C Learmonth, Robert W Motl, Brian M Sandroff, John H Pula, Diego Cadavid

Abstract

Background: The Patient Determined Disease Steps (PDDS) is a promising patient-reported outcome (PRO) of disability in multiple sclerosis (MS). To date, there is limited evidence regarding the validity of PDDS scores, despite its sound conceptual development and broad inclusion in MS research. This study examined the validity of the PDDS based on (1) the association with Expanded Disability Status Scale (EDSS) scores and (2) the pattern of associations between PDDS and EDSS scores with Functional System (FS) scores as well as ambulatory and other outcomes.

Methods: 96 persons with MS provided demographic/clinical information, completed the PDDS and other PROs including the Multiple Sclerosis Walking Scale-12 (MSWS-12), and underwent a neurological examination for generating FS and EDSS scores. Participants completed assessments of cognition, ambulation including the 6-minute walk (6 MW), and wore an accelerometer during waking hours over seven days.

Results: There was a strong correlation between EDSS and PDDS scores (ρ = .783). PDDS and EDSS scores were strongly correlated with Pyramidal (ρ = .578 &ρ = .647, respectively) and Cerebellar (ρ = .501 &ρ = .528, respectively) FS scores as well as 6 MW distance (ρ = .704 &ρ = .805, respectively), MSWS-12 scores (ρ = .801 &ρ = .729, respectively), and accelerometer steps/day (ρ = -.740 &ρ = -.717, respectively).

Conclusion: This study provides novel evidence supporting the PDDS as valid PRO of disability in MS.

Figures

Figure 1
Figure 1
Scatterplot along with line of best fit and 95% confidence intervals of Expand Disability Status Scale (EDSS) and Patient Determined Disease Steps (PDDS) scores in 96 patients with multiple sclerosis.

References

    1. Kurtzke JF. Rating Neurologic Impairment in Multiple Sclerosis an Expanded Disability Status Scale (EDSS) Neurology. 1983;33:1444–1444. doi: 10.1212/WNL.33.11.1444.
    1. Goldman MD, Motl RW, Rudick RA. Possible clinical outcome measures for clinical trials in patients with multiple sclerosis. Ther Adv Neurol Disord. 2010;3(4):229–39. doi: 10.1177/1756285610374117.
    1. Hohol MJ, Orav EJ, Weiner HL. Disease Steps in multiple sclerosis: A simple approach to evaluate disease progression. Neurology. 1995;45:251–255. doi: 10.1212/WNL.45.2.251.
    1. Hohol MJ, Orav EJ, Weiner HL. Disease steps in multiple sclerosis: A longitudinal study comparing Disease Steps and EDSS to evaluate disease progression. Mult Scler. 1999;5:349–354.
    1. Schwartz CE, Vollmer T, Lee H. Reliability and validity of two self-report measures of impairment and disability for MS. Neurology. 1999;52:63–70. doi: 10.1212/WNL.52.1.63.
    1. Rizzo MA, Hadjimichael OC, Preiningerova J, Vollmer TL. Prevalence and treatment of spasticity reported by multiple sclerosis patients. Mult Scler. 2004;10:589–595. doi: 10.1191/1352458504ms1085oa.
    1. Marrie RA, Goldman M. Validity of performance scales for disability assessment in multiple sclerosis. Mult Scler. 2007;13:1176–1182. doi: 10.1177/1352458507078388.
    1. Lo AC, Hadjimichael O, Vollmer TL. Treatment patterns of multiple sclerosis patients: A comparison of veterans and non-veterans using the NARCOMS registry. Mult Scler. 2005;11:33–40. doi: 10.1191/1352458505ms1136oa.
    1. Kobelt G, Berg J, Atherly D, Hadjimichael O. Costs and quality of life in multiple sclerosis: A cross-sectional study in the United States. Neurology. 2006;66:1696–1702. doi: 10.1212/01.wnl.0000218309.01322.5c.
    1. Marrie RA, Cutter G, Tyry T, Vollmer T, Campagnolo D. Does multiple sclerosis-associated disability differ between races? Neurology. 2006;66:1235–1240. doi: 10.1212/01.wnl.0000208505.81912.82.
    1. Hadjimichael O, Kerns RD, Rizzo MA, Cutter G, Vollmer T. Persistent pain and uncomfortable sensations in persons with multiple sclerosis. Pain. 2007;127:35–41. doi: 10.1016/j.pain.2006.07.015.
    1. Hadjimichael O, Vollmer T, Oleen-Burkey M. Fatigue characteristics in multiple sclerosis: The North American Research Committee on Multiple Sclerosis (NARCOMS) survey. Health Qual Life Outcomes. 2008;6:100. doi: 10.1186/1477-7525-6-100.
    1. Julian LJ, Vella L, Vollmer T, Hadjimichael O, Mohr DC. Employment in multiple sclerosis: exiting and re-entering the work force. J Neurol. 2008;255:1354–1360. doi: 10.1007/s00415-008-0910-y.
    1. Marrie RA, Horwitz R, Cutter G, Tyry T, Campagnolo D, Vollmer T. Comorbidity delays diagnosis and increases disability at diagnosis in MS. Neurology. 2009;72:117–124. doi: 10.1212/01.wnl.0000333252.78173.5f.
    1. Marrie RA, Rudick R, Horwitz R, Cutter G, Tyry T, Campagnolo D, Vollmer T. Vascular comorbidity in associated with more rapid disability progression in multiple sclerosis. Neurology. 2010;74:1041–1047. doi: 10.1212/WNL.0b013e3181d6b125.
    1. Motl RW, McAuley E, Snook EM, Gliottoni RC. Physical activity and quality of life in multiple sclerosis: Intermediary roles of disability, fatigue, mood, pain, self-efficacy, and social support. Health Psych Med. 2009;14:111–124. doi: 10.1080/13548500802241902.
    1. Gulick EE, Goodman S. Physical activity among people with multiple sclerosis. Int J MS Care. 2006;8:121–129. doi: 10.7224/1537-2073-8.4.121.
    1. Motl RW, Dlugonski D, Suh Y, Weikert M, Fernhall B, Goldman M. Accelerometry and its association with objective markers of walking limitations in ambulatory adults with multiple sclerosis. Arch Phys Med Rehabil. 2010;91:1942–1947. doi: 10.1016/j.apmr.2010.08.011.
    1. Polman CH, Reingold SC, Edan G, Filippi M, Hartung HP, Kappos L, Lublin FD, Metz LM, McFarland HF, O’Connor PW. Diagnostic criteria for multiple sclerosis: 2005 revisions to the “McDonald Criteria”. Ann Neurol. 2005;58:840–846. doi: 10.1002/ana.20703.
    1. Fischer JS, Rudick RA, Cutter GR, Reingold SC. The Multiple Sclerosis Functional Composite measure (MFSC): An integrated approach to MS clinical outcome assessment. National MS Society Clinical Outcomes Assessment Task Force. Mult Scler. 1999;5:244–50.
    1. Nilsagard Y, Lundholm C, Gunnarsson LG, Dcnison E. Clinical relevance using timed walk tests and ‘timed up and go’ testing in persons with multiple sclerosis. Physiother Res Int. 2007;12:105–114. doi: 10.1002/pri.358.
    1. Goldman MD, Marrie RA, Cohen JA. Evaluation of the six-minute walk in multiple sclerosis subjects and healthy controls. Mult Scler. 2008;14:383–390. doi: 10.1177/1352458507082607.
    1. Hobart JC, Riazi A, Lamping DL, Fitzpatrick R, Thompson AJ. Measuring the impact of MS on walking ability: The 12-item MS Walking Scale (MSWS-12) Neurology. 2003;60:31–36. doi: 10.1212/WNL.60.1.31.
    1. Motl R, McAuley E, Suy Y. Validity, invariance, and responsiveness of a self-report measure of functional limitations and disability in multiple sclerosis. Disabil Rehabil. 2010;32:1260–1271. doi: 10.3109/09638280903464463.
    1. Pearson OR, Busse ME, Van Deursen RWM, Wiles CM. Quantification of walking mobility in neurological disorders. Q J Med. 2004;97:463–475.
    1. Gronwall DM. Paced auditory serial addition task: A measure of recovery from concussion. Percept Mot Skills. 1977;44:367–373. doi: 10.2466/pms.1977.44.2.367.
    1. Smith A. Symbol digit modalities test: Manual. Los Angeles: Western Psychological Services; 1982.
    1. Rao SM, Leo GJ, Haughton VM, St. Aubin-Faubert P, Bernardin L. Correlation of magnetic resonance imaging with neuropsychological testing in multiple sclerosis. Neurology. 1989;39:161–166. doi: 10.1212/WNL.39.2.161.
    1. Rousselet GA, Pernet CR. Improving standards in brain-behavior correlation analyses. Front Hum Neurosci. 2012;6:119–130.
    1. Cohen J. Statistical power analysis for the behavioral sciences. 2. Hillsdale, NJ: Lawrence Erlbaum Associates; 1988.
    1. Steiger JH. Tests for comparing elements of a correlation matrix. Psych Bull. 1980;87:245–251.
    1. Hobart J, Freeman J, Thompson A. Kurtzke scales revisited: The application of psychometric methods to clinical intuition. Brain. 2000;123:1027–1040. doi: 10.1093/brain/123.5.1027.
    1. Kurtzke JF. Historical and clinical perspectives of the Expanded Disability Status Scale. Neuroepidemiology. 2008;31:1–9.
    1. Lechner-Scott J, Kappo L, Hofman M, Polman CH, Ronner H, Montalban X, Tintore M, Frontoni M, Buttinelli C, Amato MP. Can the Expanded Disability Status Scale be assessed by telephone? Mult Scler. 2003;9(2):154–159. doi: 10.1191/1352458503ms884oa.

Source: PubMed

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