bluuebunny/crossref_metadata_2025_split huggingface dataset:
The performance of non‐linear exchange rate models: a forecasting comparison
Authors: Boero Gianna , Marrocu Emanuela 
Published: October 2002

AbstractIn recent years there has been a considerable development in modelling non‐linearities and asymmetries in economic and financial variables. The aim of the current paper is to compare the forecasting performance of different models for the returns of three of the most traded exchange rates in terms of the US dollar, namely the French franc (FF/$), the German mark (DM/$) and the Japanese yen (Y/$). The relative performance of non‐linear models of the SETAR, STAR and GARCH types is contrasted with their linear counterparts. The results show that if attention is restricted to mean square forecast errors, the performance of the models, when distinguishable, tends to favour the linear models. The forecast performance of the models is evaluated also conditional on the regime at the forecast origin and on density forecasts. This analysis produces more evidence of forecasting gains from non‐linear models. Copyright © 2002 John Wiley & Sons, Ltd.
Forecasting daily foreign exchange rates using genetically optimized neural networks
Authors: Nag Ashok K. , Mitra Amit 
Published: October 2002

AbstractForecasting currency exchange rates is an important financial problem that has received much attention especially because of its intrinsic difficulty and practical applications. The statistical distribution of foreign exchange rates and their linear unpredictability are recurrent themes in the literature of international finance. Failure of various structural econometric models and models based on linear time series techniques to deliver superior forecasts to the simplest of all models, the simple random walk model, have prompted researchers to use various non‐linear techniques. A number of non‐linear time series models have been proposed in the recent past for obtaining accurate prediction results, in an attempt to ameliorate the performance of simple random walk models. In this paper, we use a hybrid artificial intelligence method, based on neural network and genetic algorithm for modelling daily foreign exchange rates. A detailed comparison of the proposed method with non‐linear statistical models is also performed. The results indicate superior performance of the proposed method as compared to the traditional non‐linear time series techniques and also fixed‐geometry neural network models. Copyright © 2002 John Wiley & Sons, Ltd.
A threshold stochastic volatility model
Authors: So Mike K. P. , Li W. K. , Lam K. 
Published: October 2002

AbstractThis article introduces a new model to capture simultaneously the mean and variance asymmetries in time series. Threshold non‐linearity is incorporated into the mean and variance specifications of a stochastic volatility model. Bayesian methods are adopted for parameter estimation. Forecasts of volatility and Value‐at‐Risk can also be obtained by sampling from suitable predictive distributions. Simulations demonstrate that the apparent variance asymmetry documented in the literature can be due to the neglect of mean asymmetry. Strong evidence of the mean and variance asymmetries was detected in US and Hong Kong data. Asymmetry in the variance persistence was also discovered in the Hong Kong stock market. Copyright © 2002 John Wiley & Sons, Ltd.
Paranoid delusions and hallucinations and bright light therapy in Alzheimer's disease
Authors: Schindler Shird Dieter , Graf André , Fischer Peter , Tölk Anton , Kasper Siegfried 
Published: October 2002

AbstractIntroductionBright light therapy (BLT) is becoming increasingly popular as an adjunct in the treatment of non‐SAD depression and circadian rhythm disturbances in demented patients. Although the rate of side‐effects is low, special attention should be paid when treating new groups of patients. We present the case of an 80‐year‐old woman suffering from dementia of Alzheimer's type (DAT).MethodBright light (2.500 lux) was administered two hours daily between 10 and 12 a.m. for 14 days. Changes in delusion or agitation were recorded using the confusion rating scale (CRS).ResultsOut of five patients, three already had delusional symptoms which slightly improved during the course of BLT, one patient never showed delusions before or during BLT, and one patient, which we present here, showed an increase in agitation and developed delusional symptoms. After eight days of treatment, the patient developed conjunctival irritation with marked red eyes and complained about blurred vision. After 12 days of treatment, the patient was disorientated in time and place and after 14 days the patient started to hallucinate and BLT had to be discontinued. The paranoid delusions and hallucinations stopped one day after treatment discontinuation.ConclusionLooking at all the presented evidence, BLT seems to be a useful treatment supplement in DAT patients, when suffering from delusions or agitation. On the other hand, caution should be used when using BLT in demented patients if agitation develops or increases during BLT. Copyright © 2002 John Wiley & Sons, Ltd.
Is late onset depression a prodrome to dementia?
Authors: Schweitzer Isaac , Tuckwell Virginia , O'Brien John , Ames David 
Published: October 2002

AbstractBackgroundRecent research suggests there are clinical and biological differences between late onset depression (LOD) and early‐onset depression (EOD).ObjectivesIn this paper we review clinical, epidemiological, structural neuroimaging and genetic investigations of late life depression that have been performed over the past two decades and offer evidence that LOD is often a prodromal disorder for dementia.ResultsLOD patients are more likely to have cognitive impairment and to have more deep white matter lesions (DWMLs). Evidence concerning cortical and temporal lobe atrophy is conflicting, while the ApoE 4 allele is not associated with LOD.ConclusionsIt is likely that LOD is not a prodrome for a particular type of dementia, but the majority of patients who do develop dementia will acquire Alzheimer's disease (AD) or a vascular dementia, as these are by far the most common causes of dementia. This issue requires further clarification with follow‐up of patients over the long term. Copyright © 2002 John Wiley & Sons, Ltd.
Dementia care mapping as a research tool for measuring quality of life in care settings: psychometric properties
Authors: Fossey Jane , Lee Lesley , Ballard Clive 
Published: October 2002

AbstractBackgroundThere are a paucity of validated measures focusing on quality of life for people with dementia in care facilities.MethodThe current study evaluated the internal consistency of Dementia Care Mapping (DCM) in a group of 123 people with dementia residing in care facilities and further evaluated the test retest reliability and concurrent validity of key DCM constructs in an additional group of 54 residents.ResultsThe results show good internal consistency. Well–ill being score was significantly correlated with an informant rated quality of life measure (r = 0.73, p < 0.0001) and showed good test retest reliability (r = 0.55, p < 0.0001). An abbreviated assessment period focusing on the hour before lunch showed significant correlation with the total assessment period (well–ill being score r = 0.5, p = 0.02).ConclusionThe current study indicates that DCM is a valid tool for the longitudinal evaluation of quality of life in people with dementia in care settings and that some abbreviation of the method may facilitate its use more widely. Copyright © 2002 John Wiley & Sons, Ltd.
Improving clinical descriptions to understand the effects of dementia treatment: consensus recommendations
Authors: Rockwood Kenneth , Joffres on behalf of the Halifax Consensus Conference on Und Christine 
Published: October 2002

AbstractObjectivesTo recommend how the description of clinically detectable treatment effects might be improved for antidementia drug trials.MethodConsensus conference, with review of available evidence.ResultsWe suggest widespread, systematic, qualitative studies, based on prospective observations such as the clinicians' narrative descriptions of patient's changes used in the Clinician's Interview‐Based Impressions of Change (CIBIC‐Plus), plus caregiver input. The identification of patient and caregiver expectations, and an understanding of how these expectations are met, are proposed as priorities for future study.ConclusionBetter descriptions of treatment effects can enhance our understanding of both clinical meaningfulness and cholinergic function in the brain. Copyright © 2002 John Wiley & Sons, Ltd.
The effect of age on the pharmacological management of ambulatory patients treated with depot neuroleptic medications for schizophrenia and related psychotic disorders
Authors: Mamo David C. , Sweet Robert A. , Roy Chengappa K. N. , Reddy Ravinder R. , Jeste Dilip V. 
Published: October 2002

AbstractBackgroundCross‐sectional studies indicate that, in comparison to younger patients, older schizophrenic patients have a higher risk for neuroleptic‐induced Parkinsonism and tardive dyskinesia (TD). It has been suggested, therefore, that older patients with schizophrenia could be maintained on reduced doses of conventional neuroleptics.MethodWe examined the effect of age on psychopharmacological management in a naturalistic study of a group of 165 patients with a clinical diagnosis of schizophrenia or a related psychotic disorder (age range=21–84 years; subjects ≥1;45 years n=86) treated with either haloperidol decanoate or fluphenazine decanoate.ResultsIncreasing age was not correlated with total daily dose of neuroleptics or anticholinergic medication. However, a modest negative correlation of age with daily neuroleptic dose was found in patients aged 45 years and older.ConclusionThe results of this study highlight the need for prospective assessments of depot neuroleptic dose requirements in older patients suffering from primary psychotic disorders. Copyright © 2002 John Wiley & Sons, Ltd.
Policy, organisation and practice of specialist old age psychiatry in England
Authors: Challis David , Reilly Siobhan , Hughes Jane , Burns Alistair , Gilchrist Helen , Wilson Ken 
Published: October 2002

AbstractObjectiveTo describe and compare service arrangements in old age psychiatry across England according to three broad domains: (i) levels of professional autonomy; (ii) degree of community orientation (delivery of and links with community services) and (iii) degree of integration between health and social care provision.DesignCross sectional survey of consultants in old age psychiatry in England. Potential respondents were sourced from the Royal College of Psychiatrists and Regional Advisers in Old Age Psychiatry.MeasuresA self‐administered postal questionnaire was piloted and refined. The questionnaire domains listed above reflect core policy issues for older people's services, covering the domains above.ResultsThere is marked variation in the deployment and use of professional staff in old age psychiatry, ranging from open access to multidisciplinary assessment to services only accessible by clinician referral. Patterns of linkage with primary care are likewise variable with only half of services providing the types of support recommended by the Audit Commission (2000). Community orientation was evident to a considerable extent in support to care homes and assessment practices. Links between health and social care appeared strongest in terms of liaison and training. There was less evidence of more formal integration through shared management of staff or for links with intensive home support for those with dementia.ConclusionsThe data provide a unique picture and benchmark of the configuration of old age psychiatry, a core element of mental health care in old age, after some 25 years of development in the UK. There appears to be substantial variation on all three domains of comparison. Copyright © 2002 John Wiley & Sons, Ltd.
Screening for mild cognitive impairment (MCI) utilizing combined mini‐mental‐cognitive capacity examinations for identifying dementia prodromes
Authors: Xu Gelin , Meyer John S. , Thornby John , Chowdhury Munir , Quach Minh 
Published: October 2002

AbstractObjectiveTo test correctness of results when combining Mini‐Mental State Examination (MMSE) and Cognitive Capacity Screening Examination (CCSE) for identifying mild cognitive impairment (MCI) among non‐demented elderly subjects at risk for developing dementia.MethodsA retrospective study was conducted among consecutively referred volunteers with memory complaints to a research out‐patient clinic. Two cognitive screening tests (MMSE and CCSE) were performed according to established protocol. Resulting combined screening test (termed by acronym as CMC) combined the non‐overlapping test items derived from both MMSE and CCSE. Conversion to dementia at follow‐up served as the ‘gold‐standard’ for evaluating correctness of CMC for identifying MCI.ResultsOf 351 subjects completing cognitive assessments and meeting requirements for study protocol, 84 (23.9%) developed dementia of different types within 3–6 years (3.89 ± 2.17) of follow‐up. Among these, 47 met criteria for probable Alzheimer disease (AD), 22 for probable vascular dementia (VaD), 12 for mixed AD/VaD and three for probable frontotemporal dementia. When final diagnosis of AD was used as the ‘gold standard’ for testing correctness of MCI identified by cognitive screening tests, sensitivities of MMSE, CCSE and CMC for identifying MCI were relatively 61.0%, 74.3% and 83.1% with minimum specificity set at 80%. When diagnosis of all types of dementia was used as the standard for testing predictive correctness of MCI, CCSE emerged as an optimal MCI screening test.ConclusionCombining the CCSE and MMSE screening tests resulted in higher sensitivity than was achieved by MMSE alone and maintained specificity at comparable levels for identifying MCI. The results confirmed that CMC has optimal correctness and utility as a brief cognitive test for screening MCI as a prodrome for dementia among non‐demented elderly populations. Copyright © 2002 John Wiley & Sons, Ltd.
Complaints of informal caregivers providing home care for dementia patients: The Pixel study
Authors: Thomas Philippe , Chantoin‐Merlet Stéphanie , Hazif‐Thomas Cyril , Belmin Joël , Montagne Bernard , Clément Jean‐Pierre , Lebruchec Marianne , Billon Rémy 
Published: October 2002

AbstractContextProspective study of the complaints, problems and requirements of the main caregiver providing home care for dementia patients.ObjectivesTo determine the complaints of home caregivers, how they are interrelated and what causes them.ResourcesSelf‐administered questionnaire of 42 questions on the patient and caregiver, including a list of complaints, given to the main caregiver. Medical questionnaire on the patient filled in by the attending physician, usually a specialist, freelance or salaried doctor.Results408 sets of records were compiled, concerning 236 demented women (77.1 ± 0.47 years) and 172 demented men (75.7 ± 0.57 years). In two‐thirds of cases, the main caregiver was a woman aged 60.6 ± 0.79 years. Female caregivers were more vulnerable than male caregivers. The most frequent caregiver complaint, regardless of the stage of the disease, concerned loss of motivation and withdrawal. The patient's awareness of the disorder was accompanied by a reduction in motor dysfunction and aggressiveness, but associated with a higher frequency of the complaint regarding loss of motivation reported by the caregiver. The caregivers' problems concerned mainly the absence of relief and the impossibility of having any time to themselves. Caregivers' requests for information concerned medical information, care structures and day care facilities.DiscussionThe attending physician comes into close contact with the patient, but must take into account the patient's environment. The physician can provides a separate analysis to the caregiver and does not completely answer to certain family questions or needs. He or she is not the family's prime source of information. The caregivers' requirements relate to the areas that are the attending physician's responsibility: the development and characteristics of the disease. The caregiver is anxious about the patient's future and is trapped by his or her involvement in the care, suffering greatly from the lack of relief.ConclusionsIt is necessary to change the focus of home care for dementia patients to fit the context in which they live and to allow for periods of relief for home caregivers. Copyright © 2002 John Wiley & Sons, Ltd.
The clock drawing test and questionable dementia: reliability and validity
Authors: Seigerschmidt Eva , Mösch Edelgard , Siemen Margarete , Förstl Hans , Bickel Horst 
Published: October 2002

AbstractObjectivesIn order to evaluate the suitability of the clock drawing test (CDT) for the detection of questionable dementia (QD), we assessed the inter–rater reliabilities and intercorrelations of four common scoring methods of the CDT in a sample of non‐demented subjects and determined the concurrent validity.MethodsThe study sample consisted of 253 discharged general hospital patients, aged between 65 and 85 years. Subjects were screened for cognitive impairment during their hospital stay. Four to six weeks after discharge each non‐demented patient was visited at home and interviewed by a trained psychologist. The interview procedure included a cognitive test battery incorporating the CDT, the Mini‐Mental State Examination (MMSE), the Syndrome Short Test (SKT), and a verbal fluency test (VF). The criteria of the Clinical Dementia Rating (CDR) were used to differentiate between cognitively normal subjects and those with QD. Clock drawings were scored independently and blindly by two raters according to four different methods. The agreement between raters was assessed, as well as the agreement between the different scoring methods. The association of gender, education, age, test performance and CDR‐rating with CDT scores was examined. Accuracy of the CDT for the detection of QD was calculated.ResultsInter–rater reliabilities were high for all four scoring methods. However, substantial differences among the scoring methods were observed, the proportion of abnormal test results varying between 9% and 50%. The CDT correlated significantly with MMSE, SKT and VF, but correlation coefficients were low (r = 0.13 to r = 0.32). Furthermore, CDT scores were influenced by age, gender, and education. Sensitivity of the CDT for QD was 66%, specificity was 65%; the negative predictive value was 73%, the positive predictive value 58%.ConclusionIn a sample of non‐demented elderly, the reliability of the CDT was sufficiently high, but the different scoring methods were not equivalent. When established cut‐off scores were used, the proportion of abnormal CDTs were significantly different. Concurrent validity with other common cognitive tests was unsatisfactory. The CDT lacks sufficient sensitivity and specificity for the identification of QD and should not be used alone to screen for possible prodromal stages of dementing illnesses. The association of age, gender and level of education with CDT scores should be taken into account by clinicians using the CDT. Copyright © 2002 John Wiley & Sons, Ltd.
Which factors influence cognitive decline in older adults suffering from dementing disorders?
Authors: Schäufele Martina , Bickel Horst , Weyerer Siegfried 
Published: October 2002

AbstractBackgroundAlthough extensive research has been done on dementing disorders in recent decades, their natural course and prognosis are not yet well understood. The aim of our study was to assess cognitive decline in a representative sample of demented elderly and to analyse the predictive value of a broad spectrum of sociodemographic, neurological and clinical variables.MethodsA random sample of elderly patients in primary care (n = 407) was drawn from a total of 3721 patients. The sample has been stratified according to the degree of cognitive impairment as assessed by their GPs. The patients were examined by means of a standardized research interview, including comprehensive cognitive testing (Hierarchic Dementia Scale) and the assessment of neurologic and physical impairments as well as of mental state (CAMDEX criteria). After a mean interval of 28 months, a follow‐up study was conducted using essentially the same instruments.ResultsAt baseline, 117 of the 407 patients were identified as suffering from mild, moderate, or severe dementia. The two‐year follow‐up of those patients revealed high mortality rates (53/117). The surviving patients showed significant cognitive decline, although the rate varied considerably between individuals. The rate of progression was strongly related to the initial degree of severity, but also to the use of psychotropic medication, which was associated with a more rapid deterioration.ConclusionsThere are some prognostic indicators that can help to establish the prognosis for dementia patients. The best indicator for both—the rate of cognitive decline and the probability of survival—is the severity of dementia. Copyright © 2002 John Wiley & Sons, Ltd.
Using time‐domain reflectometry to characterize shallow solute transport in an oak woodland hillslope in northern California, USA
Authors: Campbell Chris G. , Ghodrati Masoud , Garrido Fernando 
Published: October 2002

AbstractThe natural heterogeneity of water and solute movement in hillslope soils makes it difficult to accurately characterize the transport of surface‐applied pollutants without first gathering spatially distributed hydrological data. This study examined the application of time‐domain reflectometry (TDR) to measure solute transport in hillslopes. Three different plot designs were used to examine the transport of a conservative tracer in the first 50 cm of a moderately sloping soil. In the first plot, which was designed to examine spatial variability in vertical transport in a 1·2 m2 plot, a single probe per meter was found to adequately characterize vertical solute travel times. In addition, a dye and excavation study in this plot revealed lateral preferential flow in small macropores and a transport pattern where solute is focused vertically into preferential flow pathways. The bypass flow delivers solute deeper in the soil, where lateral flow occurs. The second plot, designed to capture both vertical and lateral flow, provided additional evidence confirming the flow patterns identified in the excavation of the first plot. The third plot was designed to examine lateral flow and once again preferential flow of the tracer was observed. In one instance rapid solute transport in this plot was estimated to occur in as little as 3% of the available pore space. Finally, it was demonstrated that the soil anisotropy, although partially responsible for lateral subsurface transport, may also homogenize the transport response across the hillslope by decreasing vertical solute spreading. Copyright © 2002 John Wiley & Sons, Ltd.