Dawn Langdon

Prof. Dawn Langdon

Department of Psychology, Royal Holloway, University of London, Egham, UK
orcid

Research Focus & Metrics

Academic Career Length

33Years (1994-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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21 December 2011 in Multiple Sclerosis Journal
Verified
Journal Article
Open access
DLDawn Langdon
Dawn Langdon
MAMp Amato
Mp Amato
JBJ Boringa
J Boringa
BBB Brochet
B Brochet
FFF Foley
F Foley
RBRhb Benedict
Rhb Benedict
Background: Cognitive impairment in MS impacts negatively on many patients at all disease stages and in all subtypes. Full clinical cognitive assessment is expensive, requiring expert staff and special equipment. Test versions and normative data are not available for all languages and cultures. Objective: To recommend a brief cognitive assessment for multiple sclerosis (MS) that is optimized for small centers, with one or few staff members, who may not have neuropsychological training and constructed to maximize international use. Methods: An expert committee of twelve members representing the main cultural groups that have so far contributed considerable data about MS cognitive dysfunction was convened. Following exhaustive literature review, peer-reviewed articles were selected to cover a broad spectrum of cultures and scales that targeted cognitive domains vulnerable to MS. Each was rated by two committee members and candidates scales were rated on psychometric qualities (reliability, validity, and sensitivity), international application, ease of administration, feasibility in the specified context, and acceptability to patients. Results: The committee recommended the Symbol Digit Modalities Test, if only 5 minutes was available, with the addition of the California Verbal Learning Test – Second Edition and the Brief Visuospatial Memory Test – Revised learning trials if a further 10 minutes could be allocated for testing. Conclusions: A brief cognitive assessment for MS has been recommended. A validation protocol has been prepared for language groups and validation studies have commenced.

9 August 2002 in The Clinical Neuropsychologist
Verified
Journal Article
Closed access
RBRalph HB Benedict
Ralph HB Benedict
JFJill S. Fischer
Jill S. Fischer
CACate J. Archibald
Cate J. Archibald
PAPeter A. Arnett
Peter A. Arnett
WBWilliam W. Beatty
William W. Beatty
FMFrederick Munschauer
Frederick Munschauer
Cognitive impairment is common in multiple sclerosis (MS), yet patients seen in MS clinics and neurologic practices are not routinely assessed neuropsychologically. In part, poor utilization of NP services may be attributed to a lack of consensus among neuropsychologists regarding the optimal approach for evaluating MS patients. An expert panel composed of neuropsychologists and psychologists from the United States, Canada, United Kingdom, and Australia was convened by the Consortium of MS Centers (CMSC) in April, 2001. Our objectives were to: (a) propose a minimal neuropsychological (NP) examination for clinical monitoring of MS patients and research, and (b) identify strategies for improving NP assessment of MS patients in the future. The panel reviewed pertinent literature on MS-related cognitive dysfunction, considered psychometric factors relevant to NP assessment, defined the purpose and optimal characteristics of a minimal NP examination in MS, and rated the psychometric and practical properties of...

16 July 2012 in BMC Neurology
Verified
Journal Article
Open access
PDF file
RBRalph HB Benedict
Ralph HB Benedict
MAMaria Pia Amato
Maria Pia Amato
JBJan Boringa
Jan Boringa
BRUNO BROCHETBRUNO BROCHET
BRUNO BROCHET
FFFred Foley
Fred Foley
DLDawn Langdon
Dawn Langdon
An international expert consensus committee recently recommended a brief battery of tests for cognitive evaluation in multiple sclerosis. The Brief International Cognitive Assessment for MS (BICAMS) battery includes tests of mental processing speed and memory. Recognizing that resources for validation will vary internationally, the committee identified validation priorities, to facilitate international acceptance of BICAMS. Practical matters pertaining to implementation across different languages and countries were discussed. Five steps to achieve optimal psychometric validation were proposed. In Step 1, test stimuli should be standardized for the target culture or language under consideration. In Step 2, examiner instructions must be standardized and translated, including all information from manuals necessary for administration and interpretation. In Step 3, samples of at least 65 healthy persons should be studied for normalization, matched to patients on demographics such as age, gender and education. The objective of Step 4 is test-retest reliability, which can be investigated in a small sample of MS and/or healthy volunteers over 1–3 weeks. Finally, in Step 5, criterion validity should be established by comparing MS and healthy controls. At this time, preliminary studies are underway in a number of countries as we move forward with this international assessment tool for cognition in MS.

1 June 2011 in Current Opinion in Neurology
Verified
Journal Article
Closed access
DLDawn Langdon
Dawn Langdon
A broad overview of cognition in multiple sclerosis (MS) is provided, taking account of its impact on the lives of patients, how cognitive impairment relates to disease and magnetic resonance variables, which cognitive domains are most vulnerable, the influence of depression and fatigue and what treatment options are available. The current focus is on cognitive reserve, which seems to offer some protection from the cognitive impact of MS. There is also considerable momentum with new MRI techniques and growing interest in PET studies. Cognition in MS is a priority for patients. Although understanding of the natural history of MS cognitive deficits is reasonably well understood, treatment options require further work before precise recommendations can be made on an individual basis.

24 April 2012 in Neurology
Verified
Journal Article
Closed access
PDF file
DGD.S. Goodin
D.S. Goodin
ARA.T. Reder
A.T. Reder
GEG.C. Ebers
G.C. Ebers
GCG. Cutter
G. Cutter
MKM. Kremenchutzky
M. Kremenchutzky
VKV. Knappertz
V. Knappertz
Objective: To examine the effects of interferon beta (IFNβ)-1b on all-cause mortality over 21 years in the cohort of 372 patients who participated in the pivotal randomized clinical trial (RCT), retaining (in the analysis) the original randomized treatment-assignments. Methods: For this randomized long-term cohort study, the primary outcome, defined before data collection, was the comparison of all-cause mortality between the IFNβ-1b 250 μg and placebo groups from the time of randomization through the entire 21-year follow-up interval (intention-to-treat, log-rank test for Kaplan-Meier survival curves). All other survival outcomes were secondary. Results: After a median of 21.1 years from RCT enrollment, 98.4%(366 of 372) of patients were identified, and, of these, 81 deaths were recorded (22.1% [81 of 366]). Patients originally randomly assigned to IFNβ-1b 250 μg showed a significant reduction in all-cause mortality over the 21-year period compared with placebo (p = 0.0173), with a hazard ratio of 0.532 (95% confidence interval 0.314–0.902). The hazard rate of death at long-term follow-up by Kaplan-Meier estimates was reduced by 46.8% among IFNβ-1b 250 μg–treated patients (46.0% among IFNβ-1b 50 μg–treated patients) compared with placebo. Baseline variables did not influence the observed treatment effect. Conclusions: There was a significant survival advantage in this cohort of patients receiving early IFNβ-1b treatment at either dose compared with placebo. Near-complete ascertainment, together with confirmatory findings from both active treatment groups, strengthens the evidence for an IFNβ-1b benefit on all-cause mortality. Classification of Evidence: This study provides Class III evidence that early treatment with IFNβ-1b is associated with prolonged survival in initially treatment-naive patients with relapsing-remitting multiple sclerosis.

28 August 2001 in Neurology
Verified
Journal Article
Closed access
PDF file
JHJ. C. Hobart
J. C. Hobart
DLD. L. Lamping
D. L. Lamping
JFJ. A. Freeman
J. A. Freeman
DLDawn Langdon
Dawn Langdon
DMD. L. McLellan
D. L. McLellan
ATA. J. Thompson
A. J. Thompson
Objective: To compare the 10-item Barthel Index (BI), 18-item Functional Independence Measure (FIM), and 30-item Functional Independence Measure + Functional Assessment Measure (FIM+FAM) as measures of disability outcomes for neurologic rehabilitation. Methods: A total of 149 inpatients from two rehabilitation units in South England specializing in neurologic disorders were studied. Traditional psychometric methods were used to evaluate and compare acceptability (score distributions), reliability (internal consistency, intrarater reproducibility), validity (concurrent, convergent and discriminant construct), and responsiveness (standardized response mean). Results: All three rating scales satisfied recommended criteria for reliable and valid measurement of disability, and are acceptable and responsive in this study sample. The FIM and FIM+FAM total scales are psychometrically similar measures of global disability. The BI, FIM, and FIM+FAM motor scales are psychometrically similar measures of physical disability. The FIM and FIM+FAM cognitive scales are psychometrically similar measures of physical disability. Conclusions: In the sample studied, the BI, FIM, FIM+FAM have similar measurement properties, when examined using traditional psychometric analyses. Although instruments with more items and item response categories generate more qualitative information about an outcome, they may not improve its measurement. Results highlight the importance of using recognized techniques of scale construction to develop health outcome measures.