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1.
Pediatr Transplant ; 23(6): e13527, 2019 09.
Article in English | MEDLINE | ID: mdl-31209988

ABSTRACT

Adolescent age at time of transplant has been recognized as a risk factor for renal allograft loss. Increased risk for graft failure may persist from adolescence to young adulthood. Transfer of care is hypothesized as a risk factor for non-adherence and graft loss. We explored whether kidney allograft function declined at an accelerated rate after transfer of care to adult transplant centers and whether coefficient of variation of tacrolimus (CV TAC) trough levels predicted allograft loss. Single-center, retrospective chart review was performed for pediatric kidney transplant recipients who received transplants between 1999 and 2011. Change in eGFR pre- and post-transfer was performed via a linear mixed-effects model. CV TAC was calculated in transplant recipients with TAC data pre- and post-transfer. t test was performed to determine the difference between means of CV TAC in subjects with and without allograft loss following transfer of care. Of the 138 subjects who transferred to adult care, 47 subjects with data pre- and post-transfer demonstrated a decrease in the rate of eGFR decline post-transfer from 8.0 mL/min/1.73 m2 per year to 2.1 mL/min/1.73 m2 per year, an ~80% decrease in eGFR decline post-transfer (P = 0.01). Twenty-four subjects had CV TAC data pre- and post-transfer of care. Pretransfer CV TAC for subjects with allograft loss post-transfer was significantly higher than in subjects without allograft loss (49% vs 26%, P < 0.05). Transfer of care was not independently associated with acceleration in eGFR decline. CV TAC may aid in identifying patients at risk for allograft loss post-transfer.


Subject(s)
Immunosuppressive Agents/pharmacokinetics , Kidney Transplantation , Transition to Adult Care , Adolescent , Adult , Age Factors , Allografts , Child , Female , Glomerular Filtration Rate , Graft Rejection , Graft Survival , Humans , Immunosuppressive Agents/administration & dosage , Male , Patient Compliance , Retrospective Studies , Risk Factors , Tacrolimus/adverse effects , Transplant Recipients , Treatment Outcome , Young Adult
2.
Mult Scler Relat Disord ; 24: 3-10, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29860199

ABSTRACT

The UK Multiple Sclerosis Register (UKMSR) is a large cohort study designed to capture 'real world' information about living with multiple sclerosis (MS) in the UK from diverse sources. The primary source of data is directly from people with Multiple Sclerosis (pwMS) captured by longitudinal questionnaires via an internet portal. This population's diagnosis of MS is self-reported and therefore unverified. The second data source is clinical data which is captured from MS Specialist Treatment centres across the UK. This includes a clinically confirmed diagnosis of MS (by Macdonald criteria) for consented patients. A proportion of the internet population have also been consented at their hospital making comparisons possible. This dataset is called the 'linked dataset'. The purpose of this paper is to examine the characteristics of the three datasets: the self-reported portal data, clinical data and linked data, in order to assess the validity of the self-reported portal data. The internet (n = 11,021) and clinical (n = 3,003) populations were studied for key shared characteristics. We found them to be closely matched for mean age at diagnosis (clinical = 37.39, portal = 39.28) and gender ratio (female %, portal = 73.1, clinical = 75.2). The Two Sample Kolmogorov-Smirnov test was for the continuous variables to examine is they were drawn from the same distribution. The null hypothesis was rejected only for age at diagnosis (D = 0.078, p < 0.01). The populations therefore, were drawn from different distributions, as there are more patients with relapsing disease in the clinical cohort. In all other analyses performed, the populations were shown to be drawn from the same distribution. Our analysis has shown that the UKMSR portal population is highly analogous to the entirely clinical (validated) population. This supports the validity of the self-reported diagnosis and therefore that the portal population can be utilised as a viable and valid cohort of people with Multiple Sclerosis for study.


Subject(s)
Multiple Sclerosis/epidemiology , Registries , Adult , Female , Humans , Internet , Male , Middle Aged , Self Report , United Kingdom
3.
Clin Biomech (Bristol, Avon) ; 37: 22-26, 2016 08.
Article in English | MEDLINE | ID: mdl-27286554

ABSTRACT

BACKGROUND: Stretches are often prescribed to manage increased limb stiffness in people with Multiple Sclerosis. This study determined the ankle plantarflexor torque magnitude that people with Multiple Sclerosis can apply during four commonly prescribed stretches and determined the relationship between the applied torque and functional ability. METHODS: People with Multiple Sclerosis (N=27) were compared to healthy control participants (n=15). Four stretches were investigated; stretching in step standing; using a step; pulling the ankle into dorsiflexion and standing in a frame. Joint position and forces were measured using 3D motion analysis and torque transducers. Baseline ankle strength and stiffness was measured using motor driven ankle perturbations. FINDINGS: People with Multiple Sclerosis (N=27) had higher stretch reflex amplitudes and lower strength compared to the control group (n=15). People with Multiple Sclerosis achieved less lengthening of the plantarflexor muscle-tendon complex when stretching but similar ankle torques compared to controls. While stretching people with Multiple Sclerosis showed greater muscle activation in the ankle plantarflexors. Stretches in weight bearing positions produced higher plantarflexor torques. People with Multiple Sclerosis with lower functional ability preferred the more supported stretches (ankle pull and standing frame). INTERPRETATION: Stretches in weight bearing positions achieve higher ankle torques but this is in part due to increased postural activity in people with Multiple Sclerosis. Functional ability may limit stretch effectiveness.


Subject(s)
Ankle Joint/physiopathology , Exercise Therapy/methods , Multiple Sclerosis/physiopathology , Muscle, Skeletal/physiopathology , Reflex, Stretch/physiology , Adult , Aged , Ankle/physiopathology , Elasticity/physiology , Female , Humans , Male , Middle Aged , Multiple Sclerosis/rehabilitation , Muscle Contraction/physiology , Tendons/physiopathology , Torque
4.
Mult Scler ; 19(6): 806-15, 2013 May.
Article in English | MEDLINE | ID: mdl-23095289

ABSTRACT

BACKGROUND: Hand dysfunction is common in multiple sclerosis (MS). Recent interest has focused on incorporating patient-reported outcome (PRO) instruments into clinical trials. Nevertheless, examinations are rare in MS of existing manual ability measures. OBJECTIVES: The objective of this paper is to evaluate the 23-item ABILHAND, developed for use after stroke, in people with MS, comparing the findings from two psychometric approaches. METHODS: We analysed ABILHAND data from 300 people with MS using: 1) traditional psychometric methods (data completeness, scaling assumptions, reliability, internal and external construct validity); and 2) Rasch measurement methods (including targeting, item response category ordering, data fit to the Rasch model, spread of item locations, item scoring bias, item stability, reliability, person response validity). RESULTS: Traditional psychometric methods implied ABILHAND was reliable and valid in this sample. Rasch measurement methods supported this finding. The three-category scoring function worked as intended and item fit to Rasch model expectations was acceptable. The 23 items (location range -3.16 to +2.73 logits) mapped a continuum of manual ability. Reliability was high (Person Separation Index (PSI) = 0.95). CONCLUSION: Both psychometric evaluations supported ABILHAND as a robust manual ability PRO measure for MS. Rasch measurement methods were more informative and, consistent with its role of detecting anomalies, identified ways of advancing further ABILHAND's measurement performance to reduce any potential for type II errors in clinical trials.


Subject(s)
Activities of Daily Living , Disability Evaluation , Hand/innervation , Motor Skills , Multiple Sclerosis/diagnosis , Surveys and Questionnaires , Adult , Female , Humans , Male , Middle Aged , Multiple Sclerosis/physiopathology , Multiple Sclerosis/psychology , Predictive Value of Tests , Prognosis , Psychometrics , Reproducibility of Results , Severity of Illness Index , Task Performance and Analysis
5.
Mult Scler ; 17(2): 214-22, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20947530

ABSTRACT

BACKGROUND: Few upper limb functioning patient rating scales have been used in multiple sclerosis (MS) research and none developed specifically for people with MS. OBJECTIVES: In this study, we examined the Disabilities of the Arm, Shoulder and Hand (DASH) to determine its utility as a useful, scientifically robust and clinically meaningful tool in MS. METHODS: DASH data from 300 people with MS underwent two independent phases of psychometric analyses: (1) a traditional psychometric analysis (including data quality, scaling assumptions, reliability and validity); and (2) a Rasch analysis (including response option thresholds ordering, tests of fit, spread of item locations, residual correlations, and person separation index). RESULTS: Overall, the traditional psychometric analysis supported the DASH as a reliable and valid measure of upper limb function in people with MS. However, several issues were raised by the Rasch analysis that questioned the validity of the DASH, including misfit in 13/30 items, disordered item response option thresholds for 9/30 items, and six pairs of items with high residual correlations (> 0.60). CONCLUSION: Rasch analysis highlights areas for potential improvement for the use of the DASH. Our findings further support our previous arguments that traditional psychometric methods provide weak scale evaluations and can mislead clinicians as to the reliability and validity of outcome measures.


Subject(s)
Disability Evaluation , Multiple Sclerosis/diagnosis , Psychometrics , Sickness Impact Profile , Upper Extremity/physiopathology , Activities of Daily Living , Adult , Arm/physiopathology , England , Female , Hand/physiopathology , Humans , Male , Middle Aged , Multiple Sclerosis/physiopathology , Multiple Sclerosis/psychology , Predictive Value of Tests , Prospective Studies , Reproducibility of Results , Severity of Illness Index , Shoulder/physiopathology , Surveys and Questionnaires
6.
Health Technol Assess ; 13(12): iii, ix-x, 1-177, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19216837

ABSTRACT

OBJECTIVES: In this monograph we examine the added value of new psychometric methods (Rasch measurement and Item Response Theory) over traditional psychometric approaches by comparing and contrasting their psychometric evaluations of existing sets of rating scale data. We have concentrated on Rasch measurement rather than Item Response Theory because we believe that it is the more advantageous method for health measurement from a conceptual, theoretical and practical perspective. Our intention is to provide an authoritative document that describes the principles of Rasch measurement and the practice of Rasch analysis in a clear, detailed, non-technical form that is accurate and accessible to clinicians and researchers in health measurement. REVIEW METHODS: A comparison was undertaken of traditional and new psychometric methods in five large sets of rating scale data: (1) evaluation of the Rivermead Mobility Index (RMI) in data from 666 participants in the Cannabis in Multiple Sclerosis (CAMS) study; (2) evaluation of the Multiple Sclerosis Impact Scale (MSIS-29) in data from 1725 people with multiple sclerosis; (3) evaluation of test-retest reliability of MSIS-29 in data from 150 people with multiple sclerosis; (4) examination of the use of Rasch analysis to equate scales purporting to measure the same health construct in 585 people with multiple sclerosis; and (5) comparison of relative responsiveness of the Barthel Index and Functional Independence Measure in data from 1400 people undergoing neurorehabilitation. RESULTS: Both Rasch measurement and Item Response Theory are conceptually and theoretically superior to traditional psychometric methods. Findings from each of the five studies show that Rasch analysis is empirically superior to traditional psychometric methods for evaluating rating scales, developing rating scales, analysing rating scale data, understanding and measuring stability and change, and understanding the health constructs we seek to quantify. CONCLUSIONS: There is considerable added value in using Rasch analysis rather than traditional psychometric methods in health measurement. Future research directions include the need to reproduce our findings in a range of clinical populations, detailed head-to-head comparisons of Rasch analysis and Item Response Theory, and the application of Rasch analysis to clinical practice.


Subject(s)
Models, Psychological , Multiple Sclerosis/psychology , Psychometrics/methods , Reproducibility of Results , Sickness Impact Profile , Activities of Daily Living/psychology , Evaluation Studies as Topic , Humans , Logistic Models , Mobility Limitation , Multiple Sclerosis/physiopathology , Multiple Sclerosis/therapy , Psychometrics/instrumentation , Self Efficacy
7.
Pediatr Transplant ; 12(6): 711-6, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18433414

ABSTRACT

Sensitization following renal transplant is a significant barrier to repeat transplantation in children. We report a successful DD renal transplant, with the use of PP, in an 11-yr-old girl who became highly sensitized following a prior failed transplant. She received PP treatments after failure of high-dose IVIg (Gamimune). We established the effectiveness of PP by attaining a 0% PRA and negative cross-matches after five PP treatments. Subsequently, our patient underwent a second round of scheduled PP. When the PRA was 0%, unacceptable antigens were removed from the UNOS wait list, PP was continued, and a kidney became available within 10 days. The final flow cytometry cross-match with the eventual donor was negative. This success demonstrates that coordination of desensitization by PP and advanced laboratory monitoring techniques with recent policies regarding allocation of organs to pediatric patients provides new opportunities for children awaiting transplantation. Since the transplant, our patient sustained a low-titer increase of anti-HLA antibodies. However, she has had no episodes of acute rejection and has maintained excellent graft function more than 17 months later.


Subject(s)
Kidney Transplantation/methods , Pediatrics/methods , Plasmapheresis , Antibodies, Monoclonal/therapeutic use , Antibodies, Monoclonal, Murine-Derived , Child , Female , HLA Antigens/chemistry , Histocompatibility Testing/methods , Humans , Immunoglobulins/administration & dosage , Immunophenotyping , Infusions, Intravenous , Kidney/pathology , Rituximab , Thrombosis , Tissue and Organ Procurement
8.
J Neurol ; 255(2): 246-54, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18204806

ABSTRACT

Rating scales are increasingly the primary outcome measures in clinical trials. However, clinically meaningful interpretation of such outcomes requires that the scales used satisfy basic requirements (scaling assumptions) within the data. These are rarely tested. The SF-36 is the most widely used patient-reported rating scale. Its scaling assumptions have been challenged in neurological disorders but remain untested in Parkinson's disease (PD). We therefore tested these by analyzing SF-36 data from 202 PD patients (54% men; mean age 70) to determine if it was legitimate to report scores for the eight SF-36 scales and its two summary measures of physical and mental health, and if those scores were reliable and valid. Results supported generation of the eight SF-36 scale scores and their reliabilities were generally good (> or = 0.74 in all but one instance). However, we found limitations that question the meaningfulness of four scales and other limitations that restrict the ability of four scales to detect change in clinical trials (floor/ceiling effects, 19.6-46.2 %). The two SF-36 summary measures were not found to be valid indicators of physical and mental health. This study demonstrates important limitations of the SF-36 and provides the first evidence-based guidelines for its use in PD. The limitations of the SF-36 demonstrated here may explain some unexpected findings in previous studies. However, the main implication is a general one for the clinical research community regarding requirements for reporting rating scale endpoints. Specifically, investigators should routinely provide scale evaluations based on data from within major clinical trials.


Subject(s)
Neuropsychological Tests , Parkinson Disease/physiopathology , Adult , Data Collection , Data Interpretation, Statistical , Evidence-Based Medicine , Factor Analysis, Statistical , Female , Guidelines as Topic , Health Status , Humans , Male , Mental Health , Principal Component Analysis , Quality of Life , Surveys and Questionnaires , Sweden/epidemiology , Treatment Outcome , United States/epidemiology
9.
Neurology ; 69(6): 555-63, 2007 Aug 07.
Article in English | MEDLINE | ID: mdl-17679674

ABSTRACT

BACKGROUND: Drug-induced dyskinesias are a common and disabling clinical problem in the long-term management of Parkinson disease (PD). Their management and the development of new treatments rely on rigorous and meaningful dyskinesia measurement. Although clinician-based approaches exist, patient-based measures are limited. METHOD: Potential rating scale items concerning daily activities affected by dyskinesias were generated from patients, literature review, and expert opinion. The resulting 42-item questionnaire was administered to 98 patients known to have problematic dyskinesias; 72 patients were invited to complete it twice for test-retest reliability (trt). Rasch analysis guided scale development. Results were cross-validated using traditional psychometric methods by examining scaling assumptions (item means and variances, item-total correlations), reliability (Cronbach alpha, trt), and validity (factor analysis). External validation was performed against standard dyskinesia measures: blinded video rating using modified Goetz and Abnormal Involuntary Movements Scales (AIMS), and Unified PD Rating Scale (UPDRS) questions 32-34. RESULTS: Response rates were high. Fourteen items were removed because of high missing data. The remaining items were Rasch analyzed. Two items were removed because of misfit. The resulting 26 items formed a clinically and statistically conformable set. Traditional psychometric criteria were satisfied and external validation showed good correlation with the UPDRS items and moderate to good correlation with objective dyskinesia measures. CONCLUSION: The 26-item Parkinson Disease Dyskinesia Scale (PDYS-26) satisfied multiple criteria for reliable and valid measurement. Correlations with objective measures suggest that it captures related but not identical constructs. As a patient-derived scale that generates linear measurements, it could complement existing clinician-based dyskinesia measures.


Subject(s)
Activities of Daily Living , Antiparkinson Agents/adverse effects , Dyskinesia, Drug-Induced/psychology , Outcome Assessment, Health Care , Parkinson Disease/drug therapy , Severity of Illness Index , Aged , Antiparkinson Agents/therapeutic use , Dyskinesia, Drug-Induced/etiology , Female , Humans , Male , Middle Aged , Psychometrics , Reproducibility of Results , Surveys and Questionnaires , Videotape Recording
10.
Neurology ; 67(12): 2230-2, 2006 Dec 26.
Article in English | MEDLINE | ID: mdl-17190951

ABSTRACT

We compared the responsiveness of the Cervical Dystonia Impact Profile (CDIP-58), Medical Outcome Study Short Form-Health Survey (SF-36), Functional Disability Questionnaire (FDQ), and Pain and Activities of Daily Living subscales of the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) in participants with cervical dystonia treated with botulinum toxin A. Subscales of CDIP-58 were more sensitive in detecting statistical and clinical change than comparable subscales of the SF-36, FDQ, and TWSTRS.


Subject(s)
Botulinum Toxins, Type A/therapeutic use , Neck Pain/epidemiology , Neck Pain/prevention & control , Outcome Assessment, Health Care/methods , Sickness Impact Profile , Torticollis/drug therapy , Torticollis/epidemiology , Adult , Aged , England/epidemiology , Female , Humans , Male , Middle Aged , Neck Pain/diagnosis , Prevalence , Prognosis , Psychometrics/methods , Quality of Life , Reproducibility of Results , Risk Assessment/methods , Risk Factors , Sensitivity and Specificity , Torticollis/diagnosis , Treatment Outcome
11.
Neurology ; 67(11): 2056-9, 2006 Dec 12.
Article in English | MEDLINE | ID: mdl-17159121

ABSTRACT

The Barthel Index (BI) may underestimate disability change because its items have few response options. We examined whether a similar scale with more response options (Functional Independence Measure, FIM) was more responsive (n = 1,396). The FIM had greater potential for responsiveness and identified more people who changed. However, its actual responsiveness, measured by effect sizes, equaled that of the BI. This counterintuitive finding suggests that effect sizes may be limited indicators of responsiveness.


Subject(s)
Activities of Daily Living , Disability Evaluation , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Multiple Sclerosis/epidemiology , Multiple Sclerosis/rehabilitation , Retrospective Studies , Spinal Cord Diseases/epidemiology , Spinal Cord Diseases/rehabilitation , Stroke/epidemiology , Stroke Rehabilitation
12.
J Neurol ; 253(12): 1594-602, 2006 Dec.
Article in English | MEDLINE | ID: mdl-16924398

ABSTRACT

BACKGROUND: The Multiple Sclerosis Walking Scale (MSWS-12) was developed to measure the impact of multiple sclerosis on walking. Many other disabling neurological conditions affect patients' ability to walk, and a generic measure of walking could provide valuable insights into patients' perceptions in clinical trials and epidemiological studies as well as routine clinical practice. OBJECTIVE: To evaluate the clinical usefulness and psychometric properties of the Walking Impact Scale (Walk-12), a modified version of the MSWS-12, in patients with neurological conditions. DESIGN: A prospective, observational study of 120 consecutive patients admitted for rehabilitation. The Walk-12 was used to measure the impact of neurological disability on walking. Traditional psychometric methods (data quality, scaling assumptions, targeting, reliability, validity and responsiveness) were used to assess the Walk-12. Transition questions were used on discharge to measure perception of change. Outcome was also measured using the timed walk test (TWT), Barthel Index (BI) and Functional Independence Measure (FIM). RESULTS: For the total group, missing data were few, scaling assumptions were satisfied, and internal consistency was 0.94. Correlations between the Walk-12 and TWT, BI and FIM motor score were moderate (r=-0.58, -0.26, -0.31). Responsiveness of the Walk-12 was high (effect size=1.12). Relationships between effect size and patients' and physiotherapists' opinion of change in walking demonstrated good concordance. Preliminary subgroup analyses indicate satisfactory psychometric properties across different neurological conditions; however, sample numbers in these analyses are small. CONCLUSIONS: In this sample of neurologically disabled patients the Walk-12 was clinically useful and satisfied standard psychometric criteria. This provides preliminary evidence that it may be suitable as a generic measure of walking ability.


Subject(s)
Diagnostic Techniques, Neurological/standards , Nervous System Diseases/physiopathology , Psychometrics/methods , Walking , Adolescent , Adult , Aged , Aged, 80 and over , Disability Evaluation , Female , Humans , Male , Middle Aged , Outcome Assessment, Health Care , Prospective Studies , Reproducibility of Results , Retrospective Studies , Severity of Illness Index
13.
Neurology ; 67(1): 39-44, 2006 Jul 11.
Article in English | MEDLINE | ID: mdl-16832075

ABSTRACT

OBJECTIVE: To develop a new patient-reported outcome measure for progressive supranuclear palsy (PSP) and to test its psychometric properties. METHODS: First, the authors generated a pool of potential scale items from in-depth patient interviews. Second, the authors administered these items, in the form of a questionnaire, to a sample of people with PSP and traditional psychometric methods were used to develop a rating scale satisfying standard criteria for reliability and validity. Third, the authors examined the psychometric properties of the rating scale in a second sample. RESULTS: In stage 1, a pool of 87 items was generated from 27 patient interviews. In stage 2, a scale with two subscales (physical, 22 items; mental, 23 items), satisfying standard criteria for reliability and validity, was developed from the response data of 225 patients with PSP. In stage 3, the scale was examined in 188 people with PSP. Missing data were low, scores in both subscales were evenly distributed, floor and ceiling effects were small. Reliability was high (Cronbach's alpha 0.93, 0.95; test-retest 0.95, 0.92). Validity was supported by the interscale intercorrelation (0.60), factor analysis, and the magnitude and pattern of correlations with four other rating scales, disease severity, and disease duration. The psychometric properties of the new scale were similar in the United Kingdom and North America, and in clinic- and community-based samples studied. CONCLUSIONS: The Progressive Supranuclear Palsy Quality of Life scale (PSP-QoL) may be a helpful patient-reported scale for clinical trials and studies in PSP.


Subject(s)
Outcome Assessment, Health Care , Psychometrics/methods , Quality of Life , Supranuclear Palsy, Progressive/psychology , Surveys and Questionnaires/standards , Aged , Humans , Middle Aged , Reproducibility of Results , Sickness Impact Profile , Supranuclear Palsy, Progressive/physiopathology
14.
J Neurol Neurosurg Psychiatry ; 77(10): 1157-62, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16820417

ABSTRACT

BACKGROUND: The use of self-report measurements in clinical settings has increased. The underlying assumption for self-report measurements is that the patient understands the questions fully and is able to give a reliable assessment of his or her own health status. This might be problematic in patients with limitations that interfere with reliable self-assessment such as cognitive impairment or serious mood disturbances, as may be the case in multiple sclerosis. In these situations proxies may provide valuable information, provided we can be certain that proxies and patients give consistent ratings. OBJECTIVE: To examine whether patients with multiple sclerosis and their partners agree on the impact of multiple sclerosis on the daily life of the patient by using the Multiple Sclerosis Impact Scale (MSIS-29). METHODS: 59 patients with multiple sclerosis and their partners completed the MSIS-29. Agreement was examined, comprehensively at scale score levels and item functioning, using both traditional and less conventional psychometric methods (Rasch analysis). RESULTS: Agreement between patients and partners was good for the physical scale, and slightly less but still adequate for the psychological scale. Mean directional differences did not show considerable systematic bias between patients and proxies. Intraclass correlation coefficients (ICCs) satisfied the requirements for agreement, but were higher for the physical scale (0.81) than for the psychological scale (0.72). These findings were supported by Rasch analyses. CONCLUSION: In this sample, albeit small, partners provided accurate estimates of the impact of multiple sclerosis. This supports the value of self-rating scales and indicates that partners might be useful sources of information when assessing the impact of multiple sclerosis on the daily life of patients.


Subject(s)
Multiple Sclerosis/complications , Proxy , Adult , Female , Health Status , Humans , Male , Middle Aged , Observer Variation , Reproducibility of Results , Self-Assessment , Severity of Illness Index
15.
Brain ; 129(Pt 1): 224-34, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16280352

ABSTRACT

Spasticity is most commonly defined as an inappropriate, velocity dependent, increase in muscle tonic stretch reflexes, due to the amplified reactivity of motor segments to sensory input. It forms one component of the upper motor neuron syndrome and often leads to muscle stiffness and disability. Spasticity can, therefore, be measured through electrophysiological, biomechanical and clinical evaluation, the last most commonly using the Ashworth scale. None of these techniques incorporate the patient experience of spasticity, nor how it affects people's daily lives. Consequently, we set out to construct a rating scale to quantify the perspectives of the impact of spasticity on people with multiple sclerosis. Qualitative methods (in-depth patient interviews and focus groups, expert opinion and literature review) were used to develop a conceptual framework of spasticity impact, and to generate a pool of items with the potential to convert this framework into a rating scale with multiple dimensions. This item pool was administered, in the form of a questionnaire, to a sample of people with multiple sclerosis and spasticity. Guided by Rasch analysis, we constructed and validated a rating scale for each component of the conceptual framework. Decisions regarding item selection were based on the integration and assimilation of seven specific analyses including clinical meaning, ordering of thresholds, fit statistics and differential item functioning. The qualitative phase (17 patient interviews, 3 focus groups) generated 144 potential scale items and a conceptual model with eight components addressing symptoms (muscle stiffness, pain and discomfort and muscle spasms,), physical impact (activities of daily living, walking and body movements) and psychosocial impact (emotional health, social functioning). The first postal survey was sent to 272 people with multiple sclerosis and had a response rate of 88%. Findings supported the development of scales for each component but demonstrated that five item response options were too many. The 144-item questionnaire, reformatted with four-item response options, was administered with four validating instruments to an independent sample of 259 people with multiple sclerosis (response rate 78%). From the responses, an 88-item instrument with eight subscales was developed that satisfied criteria for reliable and valid measurement. Correlations with other measures were consistent with predictions. The 88-item Multiple Sclerosis Spasticity Scale (MSSS-88) is a reliable and valid, patient-based, interval-level measure of the impact of spasticity in multiple sclerosis. It has the potential to advance outcomes measurement in clinical trials and clinical practice, and provides a new perspective in the clinical evaluation of spasticity.


Subject(s)
Disability Evaluation , Multiple Sclerosis/diagnosis , Muscle Spasticity , Activities of Daily Living , Adult , Aged , Female , Health Surveys , Humans , Male , Middle Aged , Multiple Sclerosis/psychology , Psychometrics , Sickness Impact Profile , Surveys and Questionnaires
16.
Mult Scler ; 11(6): 708-12, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16320732

ABSTRACT

Data from a clinical study presented an opportunity to examine the psychometric properties of the Leeds Multiple Sclerosis Quality of Life scale (LMSQoL), which has undergone limited psychometric evaluation. LMSQoL and Multiple Sclerosis Quality of Life-54 (MSQoL-54) data were collected from 90 people with multiple sclerosis (MS) living in the community. Standard psychometric methods to examine data quality, scaling assumptions, scale to sample targeting, reliability, validity, and responsiveness were employed. The LMSQoL satisfied criteria for data quality (no missing data), scaling assumptions (item-total correlations: 0.24-0.56), reliability (Cronbach's alpha: 0.71), and demonstrated responsiveness (effect size: 0.34). Correlations between the LMSQoL and MSQoL-54 physical (range: -0.02 to -0.50) and emotional subscales (range: -0.38 to -0.65) were similar; the magnitude and pattern was not consistent with predictions based on the construct purported to be measured by the LMSQoL. The LMSQoL satisfied many psychometric criteria in this small study, however, it was difficult to interpret the validity data. From this, two fundamental measurement issues are highlighted. Firstly, current methods of examining rating scales provide only circumstantial evidence of validity; secondly, health-rating scales should be developed on the basis of clear conceptual definitions.


Subject(s)
Multiple Sclerosis, Chronic Progressive/psychology , Multiple Sclerosis, Relapsing-Remitting/psychology , Psychometrics/standards , Quality of Life , Adult , Aged , Female , Humans , Male , Middle Aged , Reproducibility of Results , Surveys and Questionnaires/standards
17.
J Neurol Neurosurg Psychiatry ; 76(11): 1539-43, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16227547

ABSTRACT

OBJECTIVES: To compare the responsiveness of the Multiple Sclerosis Impact Scale (MSIS-29) with other self report scales in three multiple sclerosis (MS) samples using a range of methods. To estimate the impact on clinical trials of differing scale responsiveness. METHODS: We studied three discrete MS samples: consecutive admissions for rehabilitation; consecutive admissions for steroid treatment of relapses; and a cohort with primary progressive MS (PPMS). All patients completed four scales at two time points: MSIS-29; Short Form 36 (SF-36); Functional Assessment of MS (FAMS); and General Health Questionnaire (GHQ-12). We determined: (1) the responsiveness of each scale in each sample (effect sizes): (2) the relative responsiveness of competing scales within each sample (relative efficiency): (3) the differential responsiveness of competing scales across the three samples (relative precision); and (4) the implications for clinical trials (samples size estimates scales to produce the same effect size). RESULTS: We studied 245 people (64 rehabilitation; 77 steroids; 104 PPMS). The most responsive physical and psychological scales in both rehabilitation and steroids samples were the MSIS-29 physical scale and the GHQ-12. However, the relative ability of different scales to detect change in the two samples was variable. Differing responsiveness implied more than a twofold impact on sample size estimates. CONCLUSIONS: The MSIS-29 was the most responsive physical and second most responsive psychological scale. Scale responsiveness differs notably within and across samples, which affects sample size calculations. Results of clinical trials are scale dependent.


Subject(s)
Multiple Sclerosis/diagnosis , Multiple Sclerosis/physiopathology , Surveys and Questionnaires , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Reproducibility of Results
18.
Neurocase ; 11(4): 246-9, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16093224

ABSTRACT

The development of psychometrically sound health-related quality of life (Hr-QoL) instruments has made it possible to assess subjectively experienced Hr-QoL quantitatively, and to incorporate Hr-QoL as a measure in medical research and clinical trials. Hr-QoL in patients with progressive supranuclear palsy (PSP) has been measured using generic (not disease-specific) instruments, or Parkinson's disease-specific scales. We give an overview of the development of a disease-specific Hr-QoL instrument for patients with PSP. Based on interviews with 27 patients with PSP a preliminary Hr-QoL instrument was developed and administered to over 300 people with PSP in the UK and US. Following psychometric analysis a rating scale with a physical and a mental subscale emerged. In this patient sample, both subscales satisfied criteria for scaling assumptions, acceptability, reliability and validity (correlations with other measures consistent with a priori hypotheses). The psychometric properties of this questionnaire are undergoing further evaluation.


Subject(s)
Psychometrics/methods , Quality of Life , Supranuclear Palsy, Progressive/psychology , Aged , Female , Humans , Male , Middle Aged , Outcome Assessment, Health Care , Reproducibility of Results , Sickness Impact Profile , Supranuclear Palsy, Progressive/physiopathology , Surveys and Questionnaires
19.
J Neurol Neurosurg Psychiatry ; 76(5): 723-8, 2005 May.
Article in English | MEDLINE | ID: mdl-15834035

ABSTRACT

BACKGROUND: Clinical databases are being used increasingly to assess outcomes in healthcare services to provide evidence of clinical effectiveness in routine clinical practice. OBJECTIVES: To explore the benefits of a database for routine collection of clinical outcomes within an inpatient neurorehabilitation setting; determine the effectiveness of inpatient neurorehabilitation in a range of neurological conditions; and determine variables influencing change in functional outcome. METHODS: Over a nine year period, demographic and diagnostic characteristics were collected for the 1458 patients admitted consecutively to a neurorehabilitation unit. The level of function was measured on admission and discharge using the Barthel Index (BI) and Functional Independence Measure (FIM). Patient perception of rehabilitation benefit was evaluated using visual analogue scales (VAS). RESULTS: Of the 1413 patients (mean (SD) age 48 (14.8), range 16 to 87) whose length of stay was more than 10 days (mean 34 (24) range 10 to 184), 282 had stroke, 614 multiple sclerosis, 248 spinal cord injuries, 93 a neuromuscular condition, and 176 other brain pathology. Patients improved in functional ability as measured by both BI and the FIM motor subscale (effect sizes 0.93 to 1.44 and 1.01 to 1.48, respectively). VAS ratings demonstrated high levels of patient perceived benefit. Diagnosis, functional activity score on admission, and length of stay were significant predictors of functional gain, explaining 44% of the variability in the change scores. CONCLUSIONS: Systematic collection, analysis, and interpretation of standardised clinical outcomes data are feasible within routine clinical practice, and provide evidence that inpatient rehabilitation is effective in improving functional level in neurologically impaired patients. These data complement those of clinical trials and are useful in informing and developing clinical and research practice.


Subject(s)
Brain/physiopathology , Central Nervous System Diseases/physiopathology , Central Nervous System Diseases/rehabilitation , Data Collection , Periodicity , Activities of Daily Living , Cognition , Communication , Demography , Hospitalization , Humans , Psychometrics , Quality Indicators, Health Care , Recovery of Function , Treatment Outcome
20.
Neurology ; 63(9): 1629-33, 2004 Nov 09.
Article in English | MEDLINE | ID: mdl-15534247

ABSTRACT

OBJECTIVES: To develop a new rating scale for measuring the health impact of cervical dystonia (CD) that includes patients' perceptions and complements existing observer dependent clinician rating scales. METHODS: Scale development was in three stages. In Stage 1, a large pool of items was generated from patient interviews (n = 25), expert opinion, and literature review. In Stage 2, these items were administered by postal survey to people with CD. The resulting data were analyzed using Rasch item analysis to construct, from the item pool, a rating scale that satisfied criteria for rigorous measurement. In Stage 3, the measurement properties of this rating scale were examined in an independent sample of people with CD. RESULTS: In Stage 1, 150 items concerning the health impact of CD were generated. In Stage 2, 556 people completed questionnaires (87% response rate) and a 58-item rating scale measuring the health impact of CD in eight areas was constructed (CD Impact Profile, CDIP-58). In Stage 3, CDIP-58 data from 391 people (87% response rate) were received. Analyses supported the measurement of eight unidimensional constructs (infit mean square range 0.62 to 1.50), item calibration (33.37 to 67.56), and patient separation statistics (2.59 to 3.38). Items demonstrated stable calibrations in subgroups of people with CD supporting the stability of the CDIP-58. CONCLUSIONS: The CDIP-58 is a reliable and valid patient-based rating scale measuring the health impact of CD in eight health dimensions.


Subject(s)
Severity of Illness Index , Torticollis/diagnosis , Adult , Aged , Female , Humans , Male , Middle Aged
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