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Background: Fatigue is a common symptom in Stroke. Several self-report scales are available to measure this debilitating symptom but concern has been expressed about their construct validity.Objective: To examine the reliability and validity of a recently developed scale for multiple sclerosis (MS) fatigue, the Neurological Fatigue Index (NFI-MS), in a sample of stroke patients.Method: Six patients with stroke participated in qualitative interviews which were analysed and the themes compared for equivalence to those derived from existing data on MS fatigue. 999 questionnaire packs were sent to those with a stroke within the past four years. Data from the four subscales, and the Summary scale of the NFI-MS were fitted to the Rasch measurement model.Results: Themes identified by stroke patients were consistent with those identified by those with MS. 282 questionnaires were returned and respondents had a mean age of 67.3 years; 62% were male, and were on average 17.2 (SD 11.4, range 2-50) months post stroke. The Physical, Cognitive and Summary scales all showed good fit to the model, were unidimensional, and free of differential item functioning by age, sex and time. The sleep scales failed to show adequate fit in their current format.Conclusion: Post stroke fatigue appears to be represented by a combination of physical and cognitive components, confirmed by both qualitative and quantitative processes. The NFI-Stroke, comprising a Physical and Cognitive subscale, and a 10-item Summary scale, meets the strictest measurement requirements. Fit to the Rasch model allows conversion of ordinal raw scores to a linear metric. [ABSTRACT FROM AUTHOR]

Background: Fatigue is a common and debilitating symptom in multiple sclerosis (MS). Best-practice guidelines suggest that health services should repeatedly assess fatigue in persons with MS. Several fatigue scales are available but concern has been expressed about their validity. The objective of this study was to examine the reliability and validity of a new scale for MS fatigue, the Neurological Fatigue Index (NFI-MS). Methods: Qualitative analysis of 40 MS patient interviews had previously contributed to a coherent definition of fatigue, and a potential 52 item set representing the salient themes. A draft questionnaire was mailed out to 1223 people with MS, and the resulting data subjected to both factor and Rasch analysis. Results: Data from 635 (51.9% response) respondents were split randomly into an 'evaluation' and 'validation' sample. Exploratory factor analysis identified four potential subscales: 'physical', 'cognitive', 'relief by diurnal sleep or rest' and 'abnormal nocturnal sleep and sleepiness'. Rasch analysis led to further item reduction and the generation of a Summary scale comprising items from the Physical and Cognitive subscales. The scales were shown to fit Rasch model expectations, across both the evaluation and validation samples. Conclusion: A simple 10-item Summary scale, together with scales measuring the physical and cognitive components of fatigue, were validated for MS fatigue. [ABSTRACT FROM AUTHOR]

Background: The objective of this research was to develop a disease-specific measure for fatigue in patients with motor neurone disease (MND) by generating data that would fit the Rasch measurement model. Fatigue was defined as reversible motor weakness and whole-body tiredness that was predominantly brought on by muscular exertion and was partially relieved by rest.Methods: Qualitative interviews were undertaken to confirm the suitability of a previously identified set of 52 neurological fatigue items as relevant to patients with MND. Patients were recruited from five U.K. MND clinics. Questionnaires were administered during clinic or by post. A sub-sample of patients completed the questionnaire again after 2-4 weeks to assess test-retest validity. Exploratory factor analyses and Rasch analysis were conducted on the item set.Results: Qualitative interviews with ten MND patients confirmed the suitability of 52 previously identified neurological fatigue items as relevant to patients with MND. 298 patients consented to completing the initial questionnaire including this item set, with an additional 78 patients completing the questionnaire a second time after 4-6 weeks. Exploratory Factor Analysis identified five potential subscales that could be conceptualised as representing: 'Energy', 'Reversible muscular weakness' (shortened to 'Weakness'), 'Concentration', 'Effects of heat' and 'Rest'. Of the original five factors, two factors 'Energy' and 'Weakness' met the expectations of the Rasch model. A higher order fatigue summary scale, consisting of items from the 'Energy' and 'Weakness' subscales, was found to fit the Rasch model and have acceptable unidimensionality. The two scales and the higher order summary scale were shown to fulfil model expectations, including assumptions of unidimensionality, local independency and an absence of differential item functioning.Conclusions: The Neurological Fatigue Index for MND (NFI-MND) is a simple, easy-to-administer fatigue scale. It consists of an 8-item fatigue summary scale in addition to separate scales for measuring fatigue experienced as reversible muscular weakness and fatigue expressed as feelings of low energy and whole body tiredness. The underlying two factor structure supports the patient concept of fatigue derived from qualitative interviews in this population. All three scales were shown to be reliable and capable of interval level measurement. [ABSTRACT FROM AUTHOR]

Background: Urgent referral for suspected central nervous system (CNS) cancer is recommended, but little analysis of the referral criteria diagnostic performance has been conducted. New 2015 NICE guidance recommends direct brain imaging for patients with symptoms with positive predictive values (PPV) of 3 %, but further guidance is needed., Methods: A 12-month retrospective evaluation of 393 patients referred under previous 2005 NICE 2-week rule criteria was conducted. Analysis was based on the three groups of symptoms forming the referral criteria, (1) CNS symptoms, (2) recent onset headaches, (3) rapidly progressive subacute focal deficit/cognitive/behavioural/personality change. Comparison was made with neuroimaging findings., Results: Twelve (3.1 %) of 383 patients who attended clinic had CNS cancer suggesting the combination of clinical judgement and application of 2005 criteria matched the 2015 guideline's PPV threshold. PPVs for the three groups of symptoms were (1) 4.1 % (95 % CIs 2.0 to 7.4 %), (2) 1.2 % (0.1 to 4.3 %) and (3) 3.7 % (0.1 to 19.0 %). Sensitivities were (1) 83.3 % (95 % CIs 51.6 to 97.9 %), (2) 16.7 % (2.1 to 48.4 %), and (3) 8.3 % (0.2 to 38.5 %); specificities were (1) 37.2 % (32.3 to 42.3 %), (2) 55.5 % (50.3 to 60.7 %) and (3) 93.0 % (89.9 to 95.4 %). Of 288 patients who underwent neuroimaging, 59 (20.5 %) had incidental findings, most commonly cerebrovascular disease., Conclusions: The 2015 guidance is less prescriptive than previous criteria making clinical judgement more important. CNS symptoms had greatest sensitivity, while PPVs for CNS symptoms and rapidly progressive subacute deficit/cognitive/behavioural/personality change were closest to 3 %. Recent onset headaches had the lowest sensitivity and PPV.

Background: The Hospital Anxiety and Depression Scale (HADS) is commonly used to assess symptoms of anxiety and depression in motor neurone disease (MND). The measure has never been specifically validated for use within this population, despite questions raised about the scale's validity. This study seeks to analyse the construct validity of the HADS in MND by fitting its data to the Rasch model., Methods: The scale was administered to 298 patients with MND. Scale assessment included model fit, differential item functioning (DIF), unidimensionality, local dependency and category threshold analysis., Results: Rasch analyses were carried out on the HADS total score as well as depression and anxiety subscales (HADS-T, D and A respectively). After removing one item from both of the seven item scales, it was possible to produce modified HADS-A and HADS-D scales which fit the Rasch model. An 11-item higher-order HADS-T total scale was found to fit the Rasch model following the removal of one further item., Conclusion: Our results suggest that a modified HADS-A and HADS-D are unidimensional, free of DIF and have good fit to the Rasch model in this population. As such they are suitable for use in MND clinics or research. The use of the modified HADS-T as a higher-order measure of psychological distress was supported by our data. Revised cut-off points are given for the modified HADS-A and HADS-D subscales.