Treatment of mental slowness: How to evaluate treatment effects. A systematic review of outcome measures

REFERENCES

• Anderson , J. R. 1993 . Rules of the mind , Hillsdale, NJ : Lawrence Erlbaum .
   Google Scholar
• Ballard , C. , Stephen , S. , Kenny , R. , Kalaria , R. , Tovee , M. and O'Brien , J. 2003 . Profile of neuropsychological deficits in older stroke survivors without dementia . Dementia and Geriatric Cognitive Disorders , 16 ( 1 ) : 52 – 56 .
   PubMed Web of Science ®Google Scholar
• Barrow , I. M. 2001 . “ Within category naming in mild traumatic brain injured and normal adults ” . In Dissertation Abstracts International: Section B: The Sciences and Engineering 62(1–B), 205
   Google Scholar
• Bate , A. J. , Mathias , J. L. and Crawford , J. R. 2001 . The covert orienting of visual attention following severe traumatic brain injury . Journal of Clinical and Experimental Neuropsychology , 23 ( 3 ) : 386 – 398 .
   PubMed Web of Science ®Google Scholar
• Bay , E. and Donders , J. 2008 . Risk factors for depressive symptoms after mild-to-moderate traumatic brain injury . Brain Injury , 22 ( 3 ) : 233 – 241 .
   PubMed Web of Science ®Google Scholar
• Bleiberg , J. , Kane , R. L. , Reeves , D. L. , Garmoe , W. S. and Halpern , E. 2000 . Factor analysis of computerized and traditional tests used in mild brain injury research . Clinical Neuropsychologist , 14 ( 3 ) : 287 – 294 .
   PubMed Web of Science ®Google Scholar
• Brodaty , H. , Sachdev , P. S. , Withall , A. , Altendorf , A. , Valenzuela , M. J. and Lorentz , L. 2005 . Frequency and clinical, neuropsychological and neuroimaging correlates of apathy following stroke. The Sydney Stroke Study . Psychology Medicine , 35 ( 12 ) : 1707 – 1716 .
   PubMed Web of Science ®Google Scholar
• Brouwer , W. H. , Withaar , F. K. , Tant , M. C. and Van Zomeren , A. H. 2002 . Attention and driving in traumatic brain injury: A question of coping with time pressure . Journal of Head Trauma Rehabilitation , 17 ( 1 ) : 1 – 15 .
   PubMed Web of Science ®Google Scholar
• Brown , D. G. J. , Burnett-Stolnack , M. , Hashimoto , N. , Hier-Wellmer , S. , Perlman , O. Z. and Seigerman , C. 1996 . The relationship of neuropsychological status and productive outcomes following traumatic brain injury . Brain Injury , 10 ( 9 ) : 663 – 676 .
   PubMed Web of Science ®Google Scholar
• Carlson , M. C. 1996 . “ The impact of past mild head injury on attention ” . In Dissertation Abstracts International: Section B: The Sciences and Engineering 57(1–B), 732
   Google Scholar
• Cicerone , K. D. 2002 . Remediation of “working attention” in mild traumatic brain injury . Brain Injury , 16 ( 3 ) : 185 – 195 .
   PubMed Web of Science ®Google Scholar
• Cicerone , K. D. , Dahlberg , C. , Kalmar , K. , Langenbahn , D. M. , Malec , J. F. Bergquist , T. F. 2000 . Evidence-based cognitive rehabilitation: Recommendations for clinical practice . Archives of Physical Medicine and Rehabilitation , 81 ( 12 ) : 1596 – 1615 .
   PubMed Web of Science ®Google Scholar
• Cicerone , K. D. , Dahlberg , C. , Malec , J. F. , Langenbahn , D. M. , Felicetti , T. Kneipp , S. 2005 . Evidence-based cognitive rehabilitation: Updated review of the literature from 1998 through 2002 . Archives of Physical Medicine and Rehabilitation , 86 : 1681 – 1692 .
   PubMed Web of Science ®Google Scholar
• Collins , L. F. and Long , C. J. 1996 . Visual reaction time and its relationship to neuropsychological test performance . Archives of Clinical Neuropsychology , 11 ( 7 ) : 613 – 623 .
   PubMed Web of Science ®Google Scholar
• Crawford , M. D. , Knight , R. G. and Alsop , B. L. 2007 . Speed of word retrieval in postconcussion syndrome . Journal of the International Neuropsychological Society , 13 ( 1 ) : 178 – 182 .
   PubMed Web of Science ®Google Scholar
• DeGuise , E. , Feyz , M. , Leblanc , J. , Richard , S. L. and Lamoureux , J. 2005 . Overview of traumatic brain injury patients at a tertiary trauma centre . Canadian Journal of Neurological Sciences , 32 ( 2 ) : 186 – 193 .
   PubMed Web of Science ®Google Scholar
• DeLuca , J. and Kalmar , J. H. 2007 . Information processing speed in clinical populations , Hove, , UK : Psychology Press .
   Google Scholar
• Dik , M. G. , Deeg , D. J. , Bouter , L. M. , Corder , E. H. , Kok , A. and Jonker , C. 2000 . Stroke and apolipoprotein E epsilon4 are independent risk factors for cognitive decline: A population-based study . Stroke , 31 ( 10 ) : 2431 – 2436 .
   PubMed Web of Science ®Google Scholar
• Duits , A. , Munnecom , T. , Van Heugten , C. and Van Oostenbrugge , R. J. 2008 . Cognitive complaints in the early phase after stroke are not indicative of cognitive impairment . Journal of Neurology, Neurosurgery and Psychiatry , 79 ( 2 ) : 143 – 146 .
   PubMed Web of Science ®Google Scholar
• Ebner , A. , Haas , J. C. , Lucking , C. H. , Schily , M. , Wallesch , C. W. and Zimmermann , P. 1986 . Event-related brain potentials (P300) and neuropsychological deficit in patients with focal brain lesions . Neuroscience Letters , 64 ( 3 ) : 330 – 334 .
   PubMed Web of Science ®Google Scholar
• Erlanger , D. M. , Kausnik , T. , Broshek , D. , Freeman , J. , Feldman , D. and Festa , J. 2002 . Development and validation of a web-based screening tool for monitoring cognitive status . Journal of Head Trauma Rehabilitation , 17 ( 5 ) : 458 – 476 .
   PubMed Web of Science ®Google Scholar
• Erlanger , D. , Feldman , D. , Kutner , K. , Kaushik , T. , Kroger , H. , Festa , J. , Barth , J. , Freeman , J. and Broshek , D. 2003 . Development and validation of a web-based neuropsychological test protocol for sports-related return-to-play decision-making . Archives of Clinical Neuropsychology , 18 ( 3 ) : 293 – 316 .
   PubMed Web of Science ®Google Scholar
• Fasotti , L. , Kovacs , F. , Eling , P. A. T. M. and Brouwer , W. H. 2000 . Time Pressure Management as a compensatory strategy training after closed head injury . Neuropsychological Rehabilitation , 10 ( 1 ) : 47 – 65 .
   Web of Science ®Google Scholar
• Fazio , V. C. , Lovell , M. R. , Pardini , J. E. and Collins , M. W. 2007 . The relation between post-concussion symptoms and neurocognitive performance in concussed athletes . NeuroRehabilitation , 22 ( 3 ) : 207 – 216 .
   PubMed Web of Science ®Google Scholar
• Felmingham , K. L. , Baguley , I. J. and Green , A. M. 2004 . Effects of diffuse axonal injury on speed of information processing following severe traumatic brain injury . Neuropsychology , 18 ( 3 ) : 564 – 571 .
   PubMed Web of Science ®Google Scholar
• Fisk , G. D. and Mennemeier , M. 2006 . Common neuropsychological deficits associated with stroke survivors' impaired performance on a useful field of view test . Perceptual Motor Skills , 102 ( 2 ) : 387 – 394 .
   PubMed Web of Science ®Google Scholar
• Formisano , R. , Bivona , U. , Brunelli , S. , Giustini , M. and Taggi , F. 2001 . Driving competence after severe brain injury: A retrospective study . Europa Medicophysica , 37 ( 4 ) : 257 – 266 .
   Google Scholar
• Fos , L. A. , Greve , K. W. , South , M. B. , Mathias , C. and Benefield , H. 2000 . Paced Visual Serial Addition Test: An alternative measure of information processing speed . Applied Neuropsychology , 7 ( 3 ) : 140 – 146 .
   PubMedGoogle Scholar
• Galski , T. , Ehle , H. T. and Williams , J. B. 1997 . Off-road driving evaluations for persons with cerebral injury: A factor analytic study of predriver and simulator testing . American Journal of Occupational Therapy , 51 ( 5 ) : 352 – 359 .
   PubMed Web of Science ®Google Scholar
• Gerritsen , M. J. , Berg , I. J. , Deelman , B. G. , Visser-Keizer , A. C. and Meyboom-de Jong , B. 2003 . Speed of information processing after unilateral stroke . Journal of Clinical and Experimental Neuropsychology , 25 ( 1 ) : 1 – 13 .
   PubMed Web of Science ®Google Scholar
• Geurts , A. C. , Knoop , J. A. and Van Limbeek , J. 1999 . Is postural control associated with mental functioning in the persistent postconcussion syndrome? . Archives of Physical Medicine and Rehabilitation , 80 ( 2 ) : 144 – 149 .
   PubMed Web of Science ®Google Scholar
• Geusgens , C. A. V. , Winkens , I. , Van Heugten , C. M. , Jolles , J. and Van den Heuvel , W. J. A. 2007 . The occurrence and measurement of transfer in cognitive rehabilitation: A critical review . Journal of Rehabilitation Medicine , 39 ( 6 ) : 425 – 439 .
   PubMed Web of Science ®Google Scholar
• Grigsby , J. , Rosenberg , N. L. and Busenbark , D. 1995 . Chronic pain is associated with deficits in information processing . Perceptual and Motor Skills , 81 ( 2 ) : 403 – 410 .
   PubMed Web of Science ®Google Scholar
• Gron , G. 1996 . Cognitive slowing in patients with acquired brain damage: An experimental approach . Journal of Clinical and Experimental Neuropsychology , 18 ( 3 ) : 406 – 415 .
   PubMed Web of Science ®Google Scholar
• Heitger , M. H. , Jones , R. D. , Dalrymple-Alford , J. C. , Frampton , C. M. , Ardagh , M. W. and Anderson , T. J. 2006 . Motor deficits and recovery during the first year following mild closed head injury . Brain Injury , 20 ( 8 ) : 807 – 824 .
   PubMed Web of Science ®Google Scholar
• Hinton-Bayre , A. D. , Geffen , G. and McFarland , K. 1997 . Mild head injury and speed of information processing: A prospective study of professional rugby league players . Journal of Clinical and Experimental Neuropsychology , 19 ( 2 ) : 275 – 289 .
   PubMed Web of Science ®Google Scholar
• Hochstenbach , J. , Mulder , T. , Van Limbeek , J. , Donders , R. and Schoonderwaldt , H. 1998 . Cognitive decline following stroke: A comprehensive study of cognitive decline following stroke . Journal of Clinical and Experimental Neuropsychology , 20 : 503 – 517 .
   PubMed Web of Science ®Google Scholar
• Iverson , G. L. , Brooks , B. L. , Collins , M. W. and Lovell , M. R. 2006 . Tracking neuropsychological recovery following concussion in sport . Brain injury , 20 ( 3 ) : 245 – 252 .
   PubMed Web of Science ®Google Scholar
• Jobe , J. B. , Smith , D. M. , Ball , K. , Tennstedt , S. L. , Marsiske , M. Willis , S. L. 2001 . ACTIVE: A cognitive intervention trial to promote independence in older adults . Controlled Clinical Trials , 22 ( 4 ) : 453 – 479 .
   PubMedGoogle Scholar
• Johnstone , B. , Schopp , L. H. , Harper , J. and Koscuilek , J. 1999 . Neuropsychological impairments, vocational outcomes, and financial costs for individuals with traumatic brain injury receiving state vocational rehabilitation services . Journal of Head Trauma Rehabilitation , 14 ( 3 ) : 220 – 232 .
   PubMed Web of Science ®Google Scholar
• Kingstone , A. , Smilek , D. , Birminghan , E. , Cameron , D. and Bischof , W. F. 2005 . “ Cognitive ethology: Giving real life to attention research ” . In Measuring the mind: speed, control and age , Edited by: Duncan , J. , McLeod , P. and Phillips , L. H. New York, NY : Oxford University Press .
   Google Scholar
• Klonoff , P. S. , Talley , M. C. , Dawson , L. K. , Myles , S. M. , Watt , L. M. , Gehrels , J. A. and Henderson , S. W. 2007 . The relationship of cognitive retraining to neurological patients' work and school status . Brain Injury , 21 ( 11 ) : 1097 – 1107 .
   PubMed Web of Science ®Google Scholar
• Korda , R. J. and Douglas , J. M. 1997 . Attention deficits in stroke patients with aphasia . Journal of Clinical and Experimental Neuropsychology , 19 ( 4 ) : 525 – 542 .
   PubMed Web of Science ®Google Scholar
• Korteling , J. E. 1990 . Perception-response speed and driving capabilities of brain damaged and older drivers . Human Factors , 32 ( 1 ) : 95 – 108 .
   PubMed Web of Science ®Google Scholar
• Laidlaw , T. M. 1993 . Hypnosis and attention deficits after closed head injury . International Journal of Clinical and Experimental Hypnosis , 41 ( 2 ) : 97 – 111 .
   PubMed Web of Science ®Google Scholar
• Lang , D. L. 2000 . “ Subtyping closed head injury patients using the Dean-Woodcock Neuropsychological Assessment System ” . Dissertation Abstracts International: Section B: The Sciences and Engineering, 60(11–B), 5804
   Google Scholar
• Lee , D. , LoGalbo , A. P. , Banos , J. H. and Novack , T. A. 2004 . Prediction of cognitive abilities 1 year following traumatic brain injury from inpatient rehabilitation cognitive screening . Rehabilitation Psychology , 49 ( 2 ) : 167 – 171 .
   Web of Science ®Google Scholar
• Leskela , M. , Hietanen , M. , Kalska , H. , Ylikoski , R. , Pohjasvaara , T. , Mantyla , R. and Erkinjuntii , T. 1999 . Executive functions and speed of mental processing in elderly patients with frontal or nonfrontal ischemic stroke . European Journal of Neurology , 6 ( 6 ) : 653 – 661 .
   PubMed Web of Science ®Google Scholar
• Lippert-Gruner , M. , Kuchta , J. , Hellmich , M. and Klug , N. 2006 . Neurobehavioural deficits after severe traumatic brain injury (TBI) . Brain Injury , 20 ( 6 ) : 569 – 574 .
   PubMed Web of Science ®Google Scholar
• Loranger , M. , Lussier , J. , Pepin , M. , Hopps , S. L. and Senecal , B. 2000 . Information-processing speed and assessment of early response latency among stroke patients . Psychology Report , 87(3 Pt 1), 893–900
   PubMed Web of Science ®Google Scholar
• Mazer , B. L. , Sofer , S. , Korner-Bitensky , N. and Gelinas , I. 2001 . Use of the UFOV to evaluate and retrain visual attention skills in clients with stroke: A pilot study . American Journal of Occupational Therapy , 55 ( 5 ) : 552 – 557 .
   PubMed Web of Science ®Google Scholar
• Millis , S. R. , Rosenthal , M. and Lourie , I. F. 1994 . Predicting community integration after traumatic brain injury with neuropsychological measures . International Journal of Neurosciences , 79 ( 3–4 ) : 165 – 167 .
   PubMedGoogle Scholar
• O'Jile , J. R. , Ryan , L. M. , Betz , B. , Parks-Levy , J. , Hilsabeck , R. C. , Rhudy , J. L. and Gouvier , W. D. 2006 . Information processing following mild head injury . Archives of Clinical Neuropsychology , 21 ( 4 ) : 293 – 296 .
   PubMed Web of Science ®Google Scholar
• Owsley , C. , Sloane , M. , McGwin , G. Jr. and Ball , K. 2002 . Timed instrumental activities of daily living tasks: Relationship to cognitive function and everyday performance assessments in older adults . Gerontology , 48 ( 4 ) : 254 – 265 .
   PubMed Web of Science ®Google Scholar
• Petry , M. C. , Crosson , B. , Gonzalez-Rothi , L. J. , Bauer , R. M. and Schauer , C. A. 1994 . Selective attention and aphasia in adults: Preliminary findings . Neuropsychologia , 32 ( 11 ) : 1397 – 1408 .
   PubMed Web of Science ®Google Scholar
• Ponsford , J. , Draper , K. and Schonberger , M. 2008 . Functional outcome 10 years after traumatic brain injury: Its relationship with demographic, injury severity, and cognitive and emotional status . Journal of the International Neuropsychological Society , 14 ( 2 ) : 233 – 242 .
   PubMed Web of Science ®Google Scholar
• Ponsford , J. L. and Kinsella , G. 1988 . Evaluation of a remedial program for attention deficits following closed head injury . Journal of Clinical and Experimental Neuropsychology , 10 ( 6 ) : 69 – 708 .
   Web of Science ®Google Scholar
• Ponsford , J. and Kinsella , G. 1991 . The use of a rating scale of attentional behavior . Neuropsychological Rehabilitation , 1 ( 4 ) : 241 – 257 .
   Google Scholar
• Ponsford , J. and Kinsella , G. 1992 . Attentional deficits following closed-head injury . Journal of Clinical and Experimental Neuropsychology , 14 ( 5 ) : 822 – 838 .
   PubMed Web of Science ®Google Scholar
• Ponsford , J. , Willmont , C. , Rothwell , A. , Cameron , P. , Kelly , A. M. , Nelms , R. , Curran , C. and Ng , K. 2000 . Factors influencing outcome following mild traumatic brain injury in adults . Journal of the International Neuropsychological Society , 6 ( 5 ) : 568 – 579 .
   PubMed Web of Science ®Google Scholar
• Ponsford , J. and Ziino , C. 2003 . Fatigue and attention following traumatic brain injury . Zeitschrift fur Neuropsychologie , 14 ( 3 ) : 155 – 163 .
   Google Scholar
• Posner , M. I. and Snyder , C. R. 1975 . “ Attention and cognitive control ” . In Information processing and cognition: The Loyola Symposium , Edited by: Solso , R. L. Hillsdale, NJ : Erlbaum .
   Google Scholar
• Pouthas , V. and Perbal , S. 2004 . Time perception depends on accurate clock mechanisms as well as unimpaired attention and memory processes . Acta Neurobiologiae Experimentalis , 64 ( 3 ) : 367 – 385 .
   PubMed Web of Science ®Google Scholar
• Rasquin , S. M. , Lodder , J. , Ponds , R. W. , Winkens , I. , Jolles , J. and Verhey , F. R. 2004 . Cognitive functioning after stroke: A one-year follow-up study . Dementia and Geriatric Cognitive Disorders , 18 : 138 – 144 .
   PubMed Web of Science ®Google Scholar
• Robertson , I. H. , Ward , T. , Ridgeway , V. and Nimmo-Smith , I. 1996 . The structure of normal human attention: The test of everyday attention . Journal of the International Neuropsychological Society , 2 : 525 – 534 .
   PubMedGoogle Scholar
• Roenker , D. L. , Cissell , G. M. , Ball , K. K. , Wadley , V. G. and Edwards , J. D. 2003 . Speed of processing and driving simulator training result in improved driving performance . Human Factors , 45 : 218 – 233 .
   PubMed Web of Science ®Google Scholar
• Ruff , R. M. , Niemann , H. , Allen , C. C. , Farrow , C. E. and Wylie , T. 1992 . The Ruff 2 and 7 Selective Attention Test: A neuropsychological application . Perceptual Motor Skills , 75(3 Pt 2), 1311–1319
   PubMed Web of Science ®Google Scholar
• Salthouse , T. A. 1996 . The processing-speed theory of adult age differences in cognition . Psychology Review , 103 ( 3 ) : 403 – 428 .
   Google Scholar
• Shiffrin , R. M. and Schneider , W. 1977 . Controlled and automatic human information processing; II: Perceptual learning, automatic attending and a general theory . Psychology Review , 84 : 127 – 190 .
   Google Scholar
• Sosnoff , J. J. , Broglio , S. P. , Hillman , C. H. and Ferrara , M. S. 2007 . Concussion does not impact intraindividual response time variability . Neuropsychology , 21 ( 6 ) : 796 – 802 .
   PubMed Web of Science ®Google Scholar
• Spikman , J. M. , Timmerman , M. E. , Van Zomeren , A. H. and Deelman , B. G. 1999 . Recovery versus retest effects in attention after closed head injury . Journal of Clinical and Experimental Neuropsychology , 21 ( 5 ) : 585 – 605 .
   PubMed Web of Science ®Google Scholar
• Stuss , D. T. , Stethem , L. L. , Hugenholtz , H. , Picton , T. , Pivik , J. and Richard , M. T. 1989 . Reaction time after head injury: Fatigue, divided and focused attention, and consistency of performance . Journal of Neurology, Neurosurgery and Psychiatry , 52 ( 6 ) : 742 – 748 .
   PubMed Web of Science ®Google Scholar
• Tate , R. L. and Broe , G. A. 1999 . Psychosocial adjustment after traumatic brain injury: What are the important variables? . Psychological Medicine , 29 ( 3 ) : 713 – 725 .
   PubMed Web of Science ®Google Scholar
• Timmerman , M. E. and Brouwer , W. H. 1999 . Slow information processing after very severe closed head injury: Impaired access to declarative knowledge and intact application and acquisition of procedural knowledge . Neuropsychologia , 37 : 467 – 478 .
   PubMed Web of Science ®Google Scholar
• Tombaugh , T. N. , Rees , L. , Stormer , P. , Harrison , A. G. and Smith , A. 2007 . The effects of mild and severe traumatic brain injury on speed of information processing as measured by the computerized tests of information processing (CTIP) . Archives of Clinical Neuropsychology , 22 ( 1 ) : 25 – 36 .
   PubMed Web of Science ®Google Scholar
• Van Zomeren , A. H. and Spikman , J. M. 2003 . “ Tempo en aandacht ” . In Niet aangeboren hersenletsel bij volwassenen. The Netherlands Edited by: Vandermeulen , J. A. M. , Derix , M. M. A. , Avezaat , C. J. J. , Mulder , Th. and Van Strien , J. W. Elsevier Gezondheidszorg
   Google Scholar
• Watt , N. and Penn , C. 2000 . Predictors and indicators of return to work following traumatic brain injury in South Africa: Findings from a preliminary experimental database . South African Journal of Psychology , 30 ( 3 ) : 27 – 37 .
   Web of Science ®Google Scholar
• Whyte , J. , Hart , T. , Vaccaro , M. , Grieb-Neff , P. , Risser , A. Polansky , M. 2004 . Effects of methylphenidate on attention deficits after traumatic brain injury: A multidimensional, randomized, controlled trial . American Journal of Physical Medicine and Rehabilitation , 8 ( 6 ) : 401 – 420 .
   Google Scholar
• Winkens , I. , Van Heugten , C. M. , Fasotti , L. , Duits , A. A. and Wade , D. T. 2006 . Manifestations of mental slowness in the daily life of stroke patients . Clinical Rehabilitation , 20 : 827 – 834 .
   PubMed Web of Science ®Google Scholar
• Winkens , I. , Van Heugten , C. M. , Fasotti , L. and Wade , D. T. 2009 . Reliability and validity of two new instruments for measuring aspects of mental slowness in the daily lives of stroke patients . Neuropsychological Rehabilitation , 19 ( 1 ) : 64 – 85 .
   PubMed Web of Science ®Google Scholar
• Winkens , I. , Van Heugten , C. M. , Wade , D. T. , Habets , E. and Fasotti , L. 2009 . Archives of Physical Medicine and Rehabilitation , 90 ( 10 ) : 1672 – 1679 .
   PubMed Web of Science ®Google Scholar
• Zhang , L. , Abreu , B. C. , Masel , B. , Scheibel , R. S. , Christiansen , C. H. Huddleston , N. 2001 . Virtual reality in the assessment of selected cognitive function after brain injury . American Journal of Physical Medicine and Rehabilitation , 80 ( 8 ) : 597 – 604 .
   PubMed Web of Science ®Google Scholar
• Zhang , L. , Abreu , B. C. , Seale , G. S. , Masel , B. , Christiansen , C. H. and Ottenbacher , K. J. 2003 . A virtual reality environment for evaluation of a daily living skill in brain injury rehabilitation: Reliability and validity . Archives of Physical Medicine and Rehabilitation , 84 ( 8 ) : 1118 – 1124 .
   PubMed Web of Science ®Google Scholar
• Zoccolotti , P. , Antonucci , G. and Judica , A. 1992 . Psychometric characteristics of two semi-structured scales for the functional evaluation of hemi-inattention in extrapersonal and personal space. Neuropsychological Rehabilitation . 2 ( 3 ) : 179 – 191 .
   Google Scholar