Interpreting scores on multiple sclerosis-specific patient reported outcome measures (the PRIMUS and U-FIS)

James Twiss, Lynda C Doward, Stephen P McKenna, Benjamin Eckert, James Twiss, Lynda C Doward, Stephen P McKenna, Benjamin Eckert

Abstract

Background: The PRIMUS is a Multiple Sclerosis (MS)-specific suite of outcome measures including assessments of QoL (PRIMUS QoL, scored 0-22) and activity limitations (PRIMUS Activities, scored 0-30). The U-FIS is a measure of fatigue impact (scored 0-66). These measures have been fully validated previously using an MS sample with mixed diagnoses. The aim of the present study was to validate the measures further in a specifically Relapse Remitting MS (RRMS) sample and to provide preliminary evidence of the responder definitions (RD; also known as minimal important difference) for these instruments.

Methods: Data were derived from a multi-country efficacy trial of MS patients with assessments at baseline and 12 months. Baseline data were used to assess the internal reliability and validity of the measures. Both anchor-based and distribution-based approaches were employed for estimating RD. Anchor-based estimates were based on published RD values for the EQ-5D and were assessed for those improving and deteriorating separately. Distribution-based estimates were based on standard error of measurement (SEM), change score equivalent to 0.30, and change score equivalent to 0.50, effect sizes (ES).

Results: The sample included 911 RRMS patients (67.3% female, age mean (SD) 36.2 (8.4) years, duration of MS mean (SD) 4.8 (5.2) years). Results showed that the PRIMUS and U-FIS had good internal consistency. Appropriate correlations were observed with comparator instruments and both measures were able to distinguish between participants based on Expanded Disability Status Scale scores and time since diagnosis. The anchor-based and distribution-based RD estimates were: PRIMUS Activities range = 1.2-2.3, PRIMUS QoL range = 1.0-2.2, and U-FIS range = 2.4-7.0.

Conclusions: The results show that the PRIMUS and U-FIS are valid instruments for use with RRMS patients. The analyses provide preliminary information on how to interpret scores on the scales. These data will be useful for assessing treatment efficacy and for powering clinical studies. TRIAL REFERENCE NUMBER: ClinicalTrials.gov Identifier NCT00340834.

References

    1. Multiple Sclerosis International Federation (MSIF) [accessed 02.12.09]. About MS.
    1. Vollmer T. The natural history of relapses in multiple sclerosis. J Neurol Sci. 2007;256(Suppl 1):5–13. doi: 10.1016/j.jns.2007.01.065.
    1. Putzki N, Fischer J, Gottwald K, Reifschneider G, Ries S, Siever A, Hoffmann F, Kafferlein W, Kausch U, Liedtke M, Kirchmeier J, Gmund S, Richter A, Schicklmaier P, Niemczyk G, Wernsdorfer C, Hartung HP. for the "Mensch im Mittelpunkt" Study Group. Quality of Life in 1000 patients with early relapsing-remitting multiple sclerosis. Eur J Neurol. 2009;16:713–20. doi: 10.1111/j.1468-1331.2009.02572.x.
    1. Murray JT. Multiple Sclerosis, the History of a Disease. New York: Demos Medical Publishing; 2005.
    1. Patten SB, Williams JVA, Barbui C, Metz LM. Major depression in multiple sclerosis a population based perspective. Neurology. 2003;61:1524–27.
    1. Montel SR, Bungener C. Coping and quality of life in one hundred and thirty five subjects with multiple sclerosis. Mult Scler. 2006;13:393–401. doi: 10.1177/1352458506071170.
    1. Ziemssen T. Multiple Sclerosis beyond EDSS: depression and fatigue. J Neurol Sci. 2009;277(Suppl 1):37–41. doi: 10.1016/S0022-510X(09)70011-5.
    1. Doward LC, McKenna SP, Meads DM, Twiss J, Eckert BJ. The Development of Patient Reported Outcome Indices for Multiple Sclerosis (PRIMUS) Mult Scler. 2009;15(9):1092–1102. doi: 10.1177/1352458509106513.
    1. Lerdal A, Celius EG, Krupp L, Dahl AA. A prospective study of patterns of fatigue in multiple sclerosis. Eur J Neurol. 2007;14:1338–43. doi: 10.1111/j.1468-1331.2007.01974.x.
    1. Meads D, Doward L, McKenna S, Fisk J, Twiss J, Eckert B. The development and validation of the Unidimensional Fatigue Impact Scale (U-FIS) Mult Scler. 2009;15:1228–1238. doi: 10.1177/1352458509106714.
    1. Pickard SA, Neary MP, Cella D. Estimation of minimally important differences in EQ-5 D utility and VAS scores in cancer. Health Qual Life Outcomes. 2007;5:70. doi: 10.1186/1477-7525-5-70.
    1. Crosby RD, Kolotkin RL, Williams GR. An integrated method to determine meaningful changes in health-related Quality of Life. J Clin Epidemiol. 2004;57:1153–1160. doi: 10.1016/j.jclinepi.2004.04.004.
    1. Hajiro T, Nishimaru K. Minimal clinically significant difference in health status: the thorny path of health status measures? Eur Respir J. 2002;19:390–391. doi: 10.1183/09031936.02.00283402.
    1. U.S. Department of Health and Human Services Food and Drug Administration Guidance for Industry. Patient-Reported Outcome Measures: Use in Medical Product Development to Support Labeling Claims. U.S. FDA; Clinical/Medical; 2009. Accessed 9th December 2009.
    1. Puhan MA, Frey M, Büchi S, Schünemann HJ. The minimal important differences of the hospital anxiety and depression scale in patients with chronic obstructive pulmonary disease. Health Qual Life Outcomes. 2008;6:46. doi: 10.1186/1477-7525-6-46.
    1. Schunemann HJ, Griffith L, Jaeschke R, Goldstein R, Stubbing D, Guyatt GH. Evaluation of the minimal important difference for the feeling thermometer and the St. George's Respiratory Questionnaire in patients with chronic airflow obstruction. J Clin Epidemiol. 2003;56(12):1170–1176. doi: 10.1016/S0895-4356(03)00115-X.
    1. Santanello NC, Zhang J, Seidenberg B, Reiss TF, Barber BL. What are minimal important changes for asthma measures in a clinical trial? Eur Respir J. 1999;14:23–27. doi: 10.1034/j.1399-3003.1999.14a06.x.
    1. Jones PW. Interpreting thresholds for a clinically significant change in health status in asthma and COPD. Eur Respir J. 2002;19:398–404. doi: 10.1183/09031936.02.00063702.
    1. Turner D, Schünemann HJ, Griffith LE, Beaton DE, Griffith AM, Critch JN, Guyatt GH. Using the entire cohort in the receiver operating characteristic analysis maximises the precision of the minimal important difference. J Clin Epidemiol. 2009;62:374–379. doi: 10.1016/j.jclinepi.2008.07.009.
    1. Stargardt T, Gonder-Frederick L, Krobot KJ, Alexander CM. Fear of Hypoglycaemia: defining a minimum clinically important difference in patients with type 2 diabetes. Health Qual Life Outcomes. 2009;7:91. doi: 10.1186/1477-7525-7-91.
    1. Guyatt GH, Osoba D, Wu AW, Wyrwich KW, Norman GR. Methods to explain the clinical significance of health status measures. Mayo Clinic proceedings. 2002;77(4):371–383. doi: 10.4065/77.4.371.
    1. Norman GR, Stratford P, Regehr G. Methodological problems in the retrospective computation of responsiveness to change: the lesson of Cronbach. J Clin Epidemiol. 1997;50:869–879. doi: 10.1016/S0895-4356(97)00097-8.
    1. Cohen J. Statistical Power Analysis for the Behavioural Sciences. New York: Academic Press; 1977.
    1. Norman GR, Sloan JA, Wyrwich KW. Interpretation of changes in health-related quality of life: the remarkable universality of half a standard deviation. Med Care. 2003;41:582–92. doi: 10.1097/00005650-200305000-00004. Review.
    1. Wyrwich KW. Minimal important difference thresholds and the standard error of measurement: is there a connection? J Biopharm Stat. 2004;14:97–110. doi: 10.1081/BIP-120028508.
    1. Beaton DE, Hogg-Johnson S, Bombadier C. Evaluating changes in health status: reliability and responsiveness of five generic health status measures in workers with musculoskeletal disorders. J Clin Epidemiol. 1997;50:79–93. doi: 10.1016/S0895-4356(96)00296-X.
    1. Turner D, Schünemann HJ, Griffith LE, Beaton DE, Griffith AM, Critch JN, Guyatt GH. The minimal detectable change cannot reliably replace the minimal important difference. J Clin Epidemiol. 2010;63:28–36. doi: 10.1016/j.jclinepi.2009.01.024.
    1. McKenna SP, Doward LC, Twiss J, Hagell P, Oprandi NC, Fisk J, Grand'Maison F, Bhan V, Arbizu T, Brassat D, Kohlmann T, Meads DM, Eckert BJ. International Development of the Patient-Reported Outcome Indices for Multiple Sclerosis (PRIMUS) Value Health. 2010. in press .
    1. Doward LC, Meads DM, Fisk J, Twiss J, Hagell P, Oprandi N, Goodman J, Grand'Maison F, Bhan V, Gonzalez B, Txomin A, Kohlmann T, Brassat D, Eckert BJ, McKenna SP. International development of the Unidimensional Fatigue Impact Scale (U-FIS) Value Health. 2010;13(4):463–468. doi: 10.1111/j.1524-4733.2010.00706.x.
    1. Kurtzke JF. Rating neurologic impairment in multiple sclerosis: an expanded disability status scale (EDSS) Neurology. 1983;33:1444–52.
    1. Cutter GR, Baier ML, Rudick RA, Cookfair DL, Fischer JS, Petkau J, Syndulko K, Weinshenker BG, Antel JP, Confavreux C, Ellison GW, Lublin F, Miller AE, Rao SM, Reingold S, Thompson A, Willoughby E. Development of a multiple sclerosis functional composite as a clinical trial outcome measure. Brain. 1999;122(Pt 5):871–82. doi: 10.1093/brain/122.5.871.
    1. Gronwall DM. Paced Auditory Serial-Addition Task: a measure of recovery from concussion. Percept Mot Skills. 1977;44:367–373.
    1. EuroQoL Group. EuroQoL - a new facility for the measurement of health-related quality of life. Health Policy. 1990;16:199–208. doi: 10.1016/0168-8510(90)90421-9.
    1. Walters SJ, Brazier JE. Comparison of the minimally important difference for two health state utility measures: EQ-5 D and SF-6D. Qual Life Res. 2005;14:1523–1532. doi: 10.1007/s11136-004-7713-0.
    1. Nunnally JC. , Jr. Psychometric Theory. New York: McGraw-Hill; 1978.
    1. Anastasi A, Urbina S. Psychological Testing. New Jersey: Prentice Hall; 1997.
    1. Fitzpatrick R, Norquist JM, Jenkinson C. Distribution-based criteria for change in health-related quality of life in Parkinson's disease. J Clin Epidemiol. 2004;57:40–44. doi: 10.1016/j.jclinepi.2003.07.003.
    1. Wyrwich KW, Nienaber NA, Tierney WM. et al.Linking clinical relevance and statistical significance in evaluating intra-individual changes in health-related quality of life. Med Care. 1999;37:469–478. doi: 10.1097/00005650-199905000-00006.
    1. Wyrwich KW, Tierney WM, Wolinsky FD. Further evidence supporting an SEM-based criterion for identifying meaningful intra-individual changes in health-related quality of life. J Clin Epidemiol. 1999;52:861–873. doi: 10.1016/S0895-4356(99)00071-2.
    1. Wyrwich KW, Tierney WM, Wolinsky FD. Using the standard error of measurement to identify important changes on the Asthma Quality of Life Questionnaire. Qual Life Res. 2002;11:1–7. doi: 10.1023/A:1014485627744.
    1. Alvarez-Lafuente R, Garcia-Montojo M, De Las Heras V, Dominguez-Mozo MI, Bartolome M, Garcia-Martinez A, Arroyo R. A two-year follow-up study: multiple sclerosis functional composite versus expanded disability status scale. Mult Scler. 2009;15(Suppl 9):55–56.
    1. Kragt JJ, Thompson AJ, Montalban X, Tintore M, Rio J, Polman CH, Uitdehaag BMJ. Responsiveness and predictive value of EDSS and MSFC in primary progressive MS. Neurology. 2008;70:1084–1091. doi: 10.1212/01.wnl.0000288179.86056.e1.
    1. Costelloe L, Hutchinson M. Is a 20% change in MSFC components clinically meaningful? Mult Scler. 2007;13:1076. doi: 10.1177/1352458507077618.
    1. Casanova B, Pascual A, Bernat A, Escutia M, Bosca I, Coret F. Learning effect on multiple sclerosis functional composite in daily clinical practice [abstract] Mult Scler. 2004;10(Suppl 2):118.
    1. Cella D, Hahn EA, Dineen K. Meaningful change in cancer-specific quality of life scores: differences between improvement and worsening. Qual Life Res. 2002;11:207–221. doi: 10.1023/A:1015276414526.
    1. Kwok T, Pope JE. Minimally important difference for patient-reported outcomes in psoriatic arthritis: Health Assessment Questionnaire and pain, fatigue, and global visual analog scales. J Rheumatol. 2010;37(5):1024–8. doi: 10.3899/jrheum.090832.
    1. Colangelo KJ, Pope JE, Peschken C. The minimally important difference for patient reported outcomes in systemic lupus erythematosus including the HAQ-DI, pain, fatigue, and SF-36. J Rheumatol. 2009;36(10):2231–7. doi: 10.3899/jrheum.090193.

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