892
Views
2
CrossRef citations to date
0
Altmetric
Articles

The complex relation between visual complaints and decline in visual, visuoperceptual and cognitive functions in people with multiple sclerosis

ORCID Icon, ORCID Icon, , , , , & ORCID Icon show all
Pages 220-243 | Received 05 Jul 2022, Accepted 05 Feb 2023, Published online: 05 Mar 2023

References

  • Baetge, S. J., Dietrich, M., Filser, M., Renner, A., Stute, N., Gasis, M., Weise, M., Lepka, K., Graf, J., Goebels, N., Hartung, H.-P., Aktas, O., Meuth, S., Albrecht, P., & Penner, I.-K. (2021). Association of retinal layer thickness with cognition in patients with multiple sclerosis. Neurology - Neuroimmunology Neuroinflammation, 8(4), e1018. https://doi.org/10.1212/NXI.0000000000001018
  • Baier, M. L., Cutter, G. R., Rudick, R. A., Miller, D., Cohen, J. A., Weinstock-Guttman, B., Mass, M., & Balcer, L. J. (2005). Low-contrast letter acuity testing captures visual dysfunction in patients with multiple sclerosis. Neurology, 64(6), 992–995. https://doi.org/10.1212/01.WNL.0000154521.40686.63
  • Baker, K. S., Gibson, S. J., Georgiou-Karistianis, N., & Giummarra, M. J. (2018). Relationship between self-reported cognitive difficulties, objective neuropsychological test performance and psychological distress in chronic pain. European Journal of Pain, 22(3), 601–613. https://doi.org/10.1002/ejp.1151
  • Balcer, L. J., Galetta, S. L., Polman, C. H., Eggenberger, E., Calabresi, P. A., Zhang, A., Scanlon, J. V., & Hyde, R. (2012). Low-contrast acuity measures visual improvement in phase 3 trial ofnatalizumab in relapsing MS. Journal of the Neurological Sciences, 318(1–2), 119–124. https://doi.org/10.1016/j.jns.2012.03.009
  • Baldwin, J. N., McKay, M. J., Hiller, C. E., Moloney, N., Nightingale, E. J., & Burns, J. (2017). Relationship between physical performance and self-reported function in healthy individuals across the lifespan. Musculoskeletal Science & Practice, 30, 10–17. doi:10.1016/J.MSKSP.2017.05.001
  • Barnes, D., & McDonald, W. I. (1992). The ocular manifestations of multiple sclerosis. 2. Abnormalities of eye movements. Journal of Neurology, Neurosurgery & Psychiatry, 55(10), 863–868. https://doi.org/10.1136/jnnp.55.10.863
  • Benedict, R. H. B., Holtzer, R., Motl, R. W., Foley, F. W., Kaur, S., Hojnacki, D., & Weinstock-Guttman, B. (2011). Upper and lower extremity motor function and cognitive impairment in multiple sclerosis. Journal of the International Neuropsychological Society, 17(4), 643–653. https://doi.org/10.1017/S1355617711000403
  • Berzins, S. A., Bulloch, A. G., Burton, J. M., Dobson, K. S., Fick, G. H., & Patten, S. B. (2017). Determinants and incidence of depression in multiple sclerosis: A prospective cohort study. Journal of Psychosomatic Research, 99, 169–176. https://doi.org/10.1016/j.jpsychores.2017.06.012
  • Bjelland, I., Dahl, A. A., Haug, T. T., & Neckelmann, D. (2002). The validity of the hospital anxiety and depression scale: An updated literature review. Journal of Psychosomatic Research, 52(2), 69–77. https://doi.org/10.1016/s0022-3999(01)00296-3
  • Brailean, A., Steptoe, A., Batty, G. D., Zaninotto, P., & Llewellyn, D. J. (2019). Are subjective memory complaints indicative of objective cognitive decline or depressive symptoms? Findings from the English longitudinal study of ageing. Journal of Psychiatric Research, 110, 143–151. https://doi.org/10.1016/j.jpsychires.2018.12.005
  • Burmester, B., Leathem, J., & Merrick, P. (2016). Subjective cognitive complaints and objective cognitive function in aging: A systematic review and meta-analysis of recent cross-sectional findings. Neuropsychology Review, 26(4), 376–393. https://doi.org/10.1007/s11065-016-9332-2
  • Canon OCT-HS100. (2013). Amsterdam: Canon Europa N.V Medical Systems Division. https://www.cmi.sk/sites/default/files/oct-hs100.pdf
  • Castro, S. M. C., Damasceno, A., Damasceno, B. P., De Vasconcellos, J. P., Reis, F., Iyeyasu, J. N., & Carvalho, K. M. d. (2013). Visual pathway abnormalities were found in most multiple sclerosis patients despite history of previous optic neuritis. Arquivos de Neuro-Psiquiatria, 71(7), 437–441. https://doi.org/10.1590/0004-282X20130058
  • Cheng, H., Laron, M., Schiffman, J. S., Tang, R. A., & Frishman, L. J. (2007). The relationship between visual field and retinal nerve fiber layer measurements in patients with multiple sclerosis. Investigative Opthalmology & Visual Science, 48(12), 5798–5805. https://doi.org/10.1167/iovs.07-0738
  • Chiaravalloti, N. D., & Deluca, J. (2008). Cognitive impairment in multiple sclerosis. The Lancet Neurology, 7(12), 1139–1151. https://doi.org/10.1016/S1474-4422(08)70259-X
  • Clough, M., Dobbing, J., Stankovich, J., Ternes, A., Kolbe, S., White, O. B., & Fielding, J. (2020). Cognitive processing speed deficits in multiple sclerosis: Dissociating sensorial and motor processing changes from cognitive processing speed. Multiple Sclerosis and Related Disorders, 38, 101533. https://doi.org/10.1016/j.msard.2019.101522.
  • Coghe, G., Corona, F., Marongiu, E., Fenu, G., Frau, J., Lorefice, L., Crisafulli, A., Galli, M., Concu, A., Marrosu, M. G., Pau, M., & Cocco, E. (2018). Fatigue, as measured using the modified fatigue impact scale, is a predictor of processing speed improvement induced by exercise in patients with multiple sclerosis: Data from a randomized controlled trial. Journal of Neurology, 265(6), 1328–1333. https://doi.org/10.1007/s00415-018-8836-5
  • Compston, A., & Coles, A. (2008). Multiple sclerosis. The Lancet, 31(372), 1502–1517. https://doi.org/10.1016/S0140-6736(08)61620-7
  • Coric, D., Balk, L. J., Verrijp, M., Eijlers, A., Schoonheim, M. M., Killestein, J., Uitdehaag, B. M., & Petzold, A. (2018). Cognitive impairment in patients with multiple sclerosis is associated with atrophy of the inner retinal layers. Multiple Sclerosis Journal, 24(2), 158–166. https://doi.org/10.1177/1352458517694090
  • Costa, S. L., Genova, H. M., Deluca, J., & Chiaravalloti, N. D. (2017). Information processing speed in multiple sclerosis: Past, present, and future. Multiple Sclerosis Journal, 23(6), 772–789. https://doi.org/10.1177/1352458516645869
  • Costello, F. (2016). Vision disturbances in multiple sclerosis. Seminars in Neurology, 36(2), 185–195. https://doi.org/10.1055/s-0036-1579692
  • Cuevas, H., Danesh, V., & Henneghan, A. (2022). Self-reported cognitive function in persons with nonneurological chronic diseases: A systematic review. Journal of Aging Research, eCollection 2018:5803337. doi:10.1155/2022/5803337
  • Dersu, I., Wiggins, M. N., Luther, A., Harper, R., & Chacko, J. (2006). Understanding visual fields, part I; goldmann perimetry. J Ophthalmic Med Technol, 2(2), 1–10.
  • de Vries, S. M., Heutink, J., Melis-Dankers, B. J. M., Vrijling, A. C. L., Cornelissen, F. W., & Tucha, O. (2018). Screening of visual perceptual disorders following acquired brain injury: A delphi study. Applied Neuropsychology: Adult, 25(3), 197–209. https://doi.org/10.1080/23279095.2016.1275636
  • Esterman, B. (1982). Functional scoring of the binocular field. Ophthalmology, 89(11), 1226–1234. https://doi.org/10.1016/s0161-6420(82)34647-3
  • Farnsworth, D. (1957). The Farnsworth-Munsell 100-Hue test for the examination of color discrimination. Munsell Color Company, Inc.
  • Felgueiras, H., Parra, J., Cruz, S., Pereira, P., Santos, A. F., Rua, A., Meira, D., Fonseca, P., Pedrosa, C., Cardoso, J. N., Almeida, C., Araújo, M., & Santos, E. (2016). Dyschromatopsia in multiple sclerosis patients: A marker of subclinical involvement? Journal of Neuro-Ophthalmology, 36(3), 275–279. https://doi.org/10.1097/WNO.0000000000000401
  • Ferris, F. L., Kassoff, A., Bresnick, G. H., & Bailey, I. (1982). New visual acuity charts for clinical research. American Journal of Ophthalmology, 94(1), 91–96. https://doi.org/10.1016/0002-9394(82)90197-0
  • Forn, C., Belenguer, A., Parcet-Ibars, M. A., & Avila, C. (2008). Information-processing speed is the primary deficit underlying the poor performance of multiple sclerosis patients in the paced auditory serial addition test (PASAT). Journal of Clinical and Experimental Neuropsychology, 30(7), 789–796. https://doi.org/10.1080/13803390701779560
  • Freed, S. A., Sprague, B. N., & Ross, L. A. (2022). Does the association between objective and subjective memory vary by age among healthy older adults? Aging, Neuropsychology, and Cognition, 1–14. https://doi.org/10.1080/13825585.2022.2143471
  • Frohman, E. M., Filippi, M., Stuve, O., Waxman, S. G., Corboy, J., Phillips, J. T., Lucchinetti, C., Wilken, J., Karandikar, N., Hemmer, B., Monson, N., De Keyser, J., Hartung, H., Steinman, L., Oksenberg, J. R., Cree, B. A. C., Hauser, S., & Racke, M. K. (2005). Characterizing the mechanisms of progression in multiple sclerosis - evidence and new hypotheses for future directions. Archives of Neurology, 62(9), 1345–1356. https://doi.org/10.1001/archneur.62.9.1345
  • Gal, R. L. (2004). Visual function more than 10 years after optic neuritis: Experience of the optic neuritis treatment trial. American Journal of Ophthalmology, 137(1), 77–83. doi:10.1016/s0002-9394(03)00862-6
  • Gangeddula, V., Ranchet, M., Akinwuntan, A. E., Bollinger, K., & Devos, H. (2017). Effect of cognitive demand on functional visual field performance in senior drivers with glaucoma. Frontiers in Aging Neuroscience, 9, 286. https://doi.org/10.3389/fnagi.2017.00286
  • Giedraitiene, N., Drukteiniene, E., Kizlaitiene, R., Cimbalas, A., Asoklis, R., & Kaubrys, G. (2021). Cognitive decline in multiple sclerosis Is related to the progression of retinal atrophy and presence of oligoclonal bands: A 5-year follow-Up study. Frontiers in Neurology, 12, 939. https://doi.org/10.3389/fneur.2021.678735
  • Gil-Casas, A., Piñero-Llorens, D. P., & Molina-Martin, A. (2021). Binocular vision in patients with multiple sclerosis. Clinical Optometry, 13, 39–49. https://doi.org/10.2147/OPTO.S286862
  • Ginsburg, A. P. (1984). A new contrast sensitivity vision test chart. Optometry and Vision Science, 61(6), 403–407. https://doi.org/10.1097/00006324-198406000-00011
  • Good, G., Schepler, A., & Nichols, J. (2005). The reliability of the Lanthony desaturated D-15 test. Optometry and Vision Science, 82(12), 1054–1059. https://doi.org/10.1097/01.opx.0000192351.63069.4a
  • Graves, J., & Balcer, L. J. (2010). Eye disorders in patients with multiple sclerosis: Natural history and management. Clin Ophthalmol. Dove Press, 4, 1409–1422. https://doi.org/10.2147/OPTH.S6383
  • Harrison, A. C., Becker, W. J., & Stell, W. K. (1987). Colour vision abnormalities in multiple sclerosis. Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques, 14(3), 279–285. https://doi.org/10.1017/S0317167100026615
  • Heijl, A. (1985). The humphrey field analyzer, construction and concepts. In A. Heijl, & E. L. Greve (Eds.), Sixth international visual field symposium. Documenta ophthalmologica proceedings series (Vol. 42, pp. 77–84). Springer. https://doi.org/10.1007/978-94-009-5512-7_10.
  • Herrero, R., Garcia-Martin, E., Almarcegui, C., Ara, J. R., Rodriguez-Mena, D., Martin, J., Otin, S., Satue, M., Pablo, L. E., & Fernandez, F. J. (2012). Progressive degeneration of the retinal nerve fiber layer in patients with multiple sclerosis. Investigative Opthalmology & Visual Science, 53(13), 8344–8349. https://doi.org/10.1167/iovs.12-10362
  • Höhne, N., Poidinger, M., Merz, F., Pfister, H., Brückl, T., Zimmermann, P., Uhr, M., Holsboer, F., & Ising, M. (2014). Increased HPA axis response to psychosocial stress in remitted depression: The influence of coping style. Biological Psychology, 103, 267–275. https://doi.org/10.1016/j.biopsycho.2014.09.008
  • Huizinga, F., Heutink, J., de Haan, G. A., van der Lijn, I., van der Feen, F. E., Vrijling, A. C. L., Melis-Dankers, B. J. M., de Vries, S. M., Tucha, O., & Koerts, J. (2020). The development of the screening of visual complaints questionnaire for patients with neurodegenerative disorders: Evaluation of psychometric features in a community sample. PLoS One, 15(4), e0232232. https://doi.org/10.1371/journal.pone.0232232
  • Jakimovski, D., Benedict, R. H. B., Weinstock-Guttman, B., Ozel, O., Fuchs, T. A., Lincoff, N., Bergsland, N., Dwyer, M. G., & Zivadinov, R. (2021). Visual deficits and cognitive assessment of multiple sclerosis: Confounder, correlate, or both? Journal of Neurology, 268(7), 2578–2588. https://doi.org/10.1007/s00415-021-10437-5
  • Jasse, L., Vukusic, S., Durand-Dubief, F., Vartin, C., Piras, C., Bernard, M., Pélisson, D., Confavreux, C., Vighetto, A., & Tilikete, C. (2013). Persistent visual impairment in multiple sclerosis: Prevalence, mechanisms and resulting disability. Multiple Sclerosis Journal, 19(12), 1618–1626. https://doi.org/10.1177/1352458513479840
  • Koerts, J., Tucha, L., Leenders, K. L., Van Beilen, M., Brouwer, W. H., & Tucha, O. (2011). Subjective and objective assessment of executive functions in Parkinson’s disease. Journal of the Neurological Sciences, 310(1–2), 172–175. doi:10.1016/J.JNS.2011.07.009
  • Koerts, J., van Beilen, M., Leenders, K. L., Brouwer, W. H., Tucha, L., & Tucha, O. (2012). Complaints about impairments in executive functions in Parkinson’s disease: the association with neuropsychological assessment. Parkinsonism & Related Disorders, 18(2), 194–197. doi:10.1016/J.PARKRELDIS.2011.10.002
  • Kooijman, A. C., Stellingwerf, N., van Schoot, E. A. J., Cornelissen, F. W., & van der W, G. J. (1994). Groningen edge contrast chart (GECKO) and glare measurements. In A.C. Kooijman, P.L. Looijestijn, J.A. Welling, & G.J. VanDerWildt (Eds.), Low vision: Research and new developments in rehabilitation (pp. 101–110). Amsterdam: IOS Press.
  • Krupp, L. B., Serafin, D. J., & Christodoulou, C. (2010). Multiple sclerosis-associated fatigue. Expert Review of Neurotherapeutics, 10(9), 1437–1447. https://doi.org/10.1586/ern.10.99
  • Kurtzke, J. F. (1983). Rating neurologic impairment in multiple sclerosis: An expanded disability status scale (EDSS). Neurology, 33(11), 1444–1452. https://doi.org/10.1212/wnl.33.11.1444
  • Lang, J. (1983). A new stereotest. Journal of Pediatric Ophthalmology & Strabismus, 20(2), 72–74. https://doi.org/10.3928/0191-3913-19830301-08
  • Lanthony, P. (1978). The desaturated panel D-15. Documenta Ophthalmologica, 46(1), 185–189. https://doi.org/10.1007/BF00174107
  • Ma, S. L., Shea, J. A., Galetta, S. L., Jacobs, D. A., Markowitz, C. E., Maguire, M. G., & Balcer, L. J. (2002). Self-reported visual dysfunction in multiple sclerosis: New data from the VFQ-25 and development of an MS-specific vision questionnaire. American Journal of Ophthalmology, 133(5), 686–692. doi:10.1016/S0002-9394(02)01337-5
  • Markowitz, S. N. (2006). Principles of modern low vision rehabilitation. Canadian Journal of Ophthalmology, 41(3), 289–312. https://doi.org/10.1139/I06-027
  • Mowry, E. M., Loguidice, M. J., Daniels, A. B., Jacobs, D. A., Markowitz, C. E., Galetta, S. L., Nano-Schiavi, M. L., Cutter, G. R., Maguire, M. G., & Balcer, L. J. (2009). Vision related quality of life in multiple sclerosis: Correlation with new measures of low and high contrast letter acuity. Journal of Neurology, Neurosurgery & Psychiatry, 80(7), 767–772. https://doi.org/10.1136/jnnp.2008.165449
  • Nerrant, E., & Tilikete, C. (2017). Ocular motor manifestations of multiple sclerosis. Journal of Neuro-Ophthalmology, 37(3), 332–340. https://doi.org/10.1097/WNO0000000000000507
  • Owsley, C., & Mcgwin, G. (2010). Vision and driving. Vision Research, 50(23), 2348–2361. https://doi.org/10.1016/j.visres.2010.05.021
  • Patoine, A., Mikula, L., Romero, S. M., Michaels, J., Keruzore, O., Chaumillon, R., Bernardin, D., & Faubert, J. (2021). Increased visual and cognitive demands emphasize the importance of meeting visual needs at all distances while driving. PLoS One, 16(3), e0247254. https://doi.org/10.1371/journal.pone.0247254
  • Portas, C. M., Strange, B. A., Friston, K. J., Dolan, R. J., & Frith, C. D. (2000). How does the brain sustain a visual percept. Proc R Soc London Ser B Biol Sci., 267(1446), 845–850. https://doi.org/10.1098/rspb.2000.1080
  • Reid, L. M., & MacLullich, A. M. J. (2006). Subjective memory complaints and cognitive impairment in older people. Dementia and Geriatric Cognitive Disorders, 22(5–6), 471–485. doi:10.1159/000096295
  • Saan, R. J., & Deelman, B. (1986). 15-Woorden test A en B [15-word test A and B.] Handboekneuropsychologische diagnostiek. In A. Bouma, J. Mulder, J. Lindeboom, & B. Schmand (Eds.), Handbook neuropsychological assessment (2nd ed, pp. 267–282). Pearson Assessment and Information BV.
  • Saidha, S., Al-Louzi, O., Ratchford, J. N., Bhargava, P., Oh, J., Newsome, S. D., Prince, J. L., Pham, D., Roy, S., van Zijl, P., Balcer, L. J., Frohman, E. M., Reich, D. S., Crainiceanu, C., & Calabresi, P. A. (2015). Optical coherence tomography reflects brain atrophy in multiple sclerosis: A four-year study. Annals of Neurology, 78(5), 801–813. https://doi.org/10.1002/ana.24487
  • Satue, M., Rodrigo, M. J., Otin, S., Bambo, M. P., Fuertes, M. I., Ara, J. R., Martin, J., Polo, V., Larossa, J.M., Pablo, L., Garcia-Martin, E., et al. (2016). Relationship between visual dysfunction and retinal changes in patients with multiple sclerosis. PloS One, 11(6), e0157293. https://doi.org/10.1371/jounral.pone.0157293
  • Schmand, B., Groenink, S. C., & Van Den Dungen, M. (2008). Letterfluency: Psychometric properties and Dutch normative data. Tijdschrift Voor Gerontologie en Geriatrie, 39(2), 64–74. https://doi.org/10.1007/BF03078128
  • Scholz, M. P., & Donders, J. (2022). Cognitive complaints in older adults: Relationships between self and informant report, objective test performance, and symptoms of depression. Neuropsychology, Development and Cognition. Section B, Neuropsychology and Cognition, 8, 1–16. doi:10.1080/13825585.2022.2144617, 1–16.
  • Schuhfried, G. (2013). Vienna test system: Psychological assessment. Moedling. Schuhfried.
  • Simons, K. (1981). A comparison of the frisby, random-Dot E, TNO, and randot circles stereotests in screening and office Use. Archives of Ophthalmology, 99(3), 446–452. doi:10.1001/archopht.1981.03930010448011
  • Sisto, D., Trojano, M., Vetrugno, M., Trabucco, T., Iliceto, G., & Sborgia, C. (2005). Subclinical visual involvement in multiple sclerosis: A study by MRI, VEPs, frequency-doubling perimetry, standard perimetry, and contrast sensitivity. Investigative Opthalmology & Visual Science, 46(4), 1264–1268. https://doi.org/10.1167/iovs.03-1213
  • Smit, D., Koerts, J., Bangma, D. F., Fuermaier, A. B. M., Tucha, L., & Tucha, O. (2021). Look who is complaining: Psychological factors predicting subjective cognitive complaints in a large community sample of older adults. Applied Neuropsychology: Adult, 1–15. https://doi.org/10.1080/23279095.2021.2007387
  • Spinhoven, P., Ormel, J., Sloekers, P. P. A., Kempen, G. I. J. M., Speckens, A. E. M., & Van Hemert, A. M. (1997). A validation study of the hospital anxiety and depression scale (HADS) in different groups of Dutch subjects. Psychological Medicine, 27(2), 363–370. https://doi.org/10.1017/S0033291796004382
  • Tilikete, C., Jasse, L., Vukusic, S., Durand-Dubief, F., Vardanian, C., Pélisson, D., & Vighetto, A. (2011). Persistent ocular motor manifestations and related visual consequences in multiple sclerosis. Annals of the New York Academy of Sciences, 1233(1), 327–334. https://doi.org/10.1111/j.1749-6632.2011.06116.x
  • van der Feen, F. E., de Haan, G. A., van der Lijn, I., Fuermaier, A. B. M., Heersema, T. J., Meilof, J. F., & Heutink, J. (2022). Confirmatory factor analysis of the Dutch screening visual complaints questionnaire in people with multiple sclerosis. Journal of Patient-Reported Outcomes, 6(1), 1–6. https://doi.org/10.1186/s41687-022-00443-0
  • van der Feen, F. E., de Haan, G. A., van der Lijn, I., Huizinga, F., Meilof, J. F., Heersema, D. J., & Heutink, J. (2022). Recognizing visual complaints in people with multiple sclerosis: Prevalence, nature and associations with key characteristics of MS. Multiple Sclerosis and Related Disorders, 57, 103429. https://doi.org/10.1016/j.msard.2021.103429.
  • van der Hiele, K., Spliethoff-Kamminga, N. G. A., Ruimschotel, R. P., Middelkoop, H. A. M., & Visser, L. H. (2012). The relationship between self-reported executive performance and psychological characteristics in multiple sclerosis. European Journal of Neurology, 19(4), 562–569. doi:10.1111/J.1468-1331.2011.03538.X
  • van der Lijn, I., de Haan, G. A., van der Feen, F. E., Huizinga, F., Fuermaier, A. B. M., van Laar, T., & Heutink, J. (2022). The screening visual complaints questionnaire (SVCq) in people with Parkinson’s disease—confirmatory factor analysis and advice for its use in clinical practice. PLoS One, 17(9), e0272559. https://doi.org/10.1371/journal.pone.0272559
  • Vleugels, L., Lafosse, C., van Nunen, A. n., Nachtergaele, S., Ketelaer, P., Charlier, M., Vandenbussche, E., et al. (2000). Visuoperceptual impairment in multiple sclerosis patients diagnosed with neuropsychological tasks. Multiple Sclerosis Journal, 6(4), 241–254. https://doi.org/10.1177/135245850000600406
  • Vuilleumier, P., & Driver, J. (2007). Modulation of visual processing by attention and emotion: Windows on causal interactions between human brain regions. Philosophical Transactions of the Royal Society B: Biological Sciences, 362(1481), 837–855. https://doi.org/10.1098/rstb.2007.2092
  • Walraven, J. (1975). Amblyopia screening with random-Dot stereograms. American Journal of Ophthalmology, 80(5), 893–900. doi:10.1016/0002-9394(75)90286-x
  • Wechsler, D. (2008). Wechsler adult intelligence scale-4th ed. Pearson.
  • Wieder, L., Gäde, G., Pech, L. M., Zimmermann, H., Wernecke, K.-D., Dörr, J.-M., Bellmann-Strobl, J., Paul, F., & Brandt, A. U. (2013). Low contrast visual acuity testing is associated with cognitive performance in multiple sclerosis: A cross-sectional pilot study. BMC Neurology, 13(1), 167. https://doi.org/10.1186/1471-2377-13-167
  • Zigmond, A., & Snaith, R. (1983). The hospital anxiety and depression scale. Acta Psychiatrica Scandinavica, 67(6), 361–370. https://doi.org/10.1111/j.1600-0447.1983.tb09716.x