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Psychometric Performance of the National Eye Institute 25-Item Visual Function Questionnaire

In Turkish Diabetic Retinopathy Patients

The Patient: Patient-Centered Outcomes Research volume 1, pages 115–125 (2008)Cite this article

Abstract

Objective: To assess the psychometric performance of the National Eye Institute 25-item Visual Function Questionnaire (NEI VFQ-25) in Turkish diabetic retinopathy patients.

Methods: Health-related quality of life was measured in a sample of 60 patients with diabetic retinopathy using both a Turkish version of the NEI VFQ-25 and the SF-36 instrument. The Turkish version of the NEI VFQ-25 was developed by following established cross-cultural adaptation and validation guidelines. After pilot testing, an interview administrator’s scale for the newly translated NEI VFQ-25 was administered to 60 diabetic retinopathy patients at Haydarpasa Numune Research and Training Hospital in Istanbul, Turkey. Reliability of the Turkish version of the NEI VFQ-25 was tested by internal consistency and test-retest reliability. Convergent validity was assessed by examining the correlation between total scores of the Turkish version of the NEI VFQ-25 and the SF-36. Principal component analysis was used to determine the best loading of items in the Turkish version of the NEI VFQ-25.

Results: The internal consistency within the domains of the NEI VFQ-25 was high, with a Cronbach’s a coefficient of 0.88 for the NEI VFQ-25 scale. Reliability of the NEI VFQ-25 was also high, with a test-retest intra-class correlation value of 0.85. Significant correlations were observed between the total scores of the NEI VFQ-25 and the SF-36.

Conclusions: Overall, the results indicated that the psychometric performance of the NEI VFQ-25 in the study sample was very strong, and the instrument was found to be valid and reliable. The instrument is likely to be suitable for use in clinical studies of chronic eye diseases in Turkey.

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References

  1. King H, Rewers M. Global estimates for prevalence of diabetes mellitus and impaired glucose tolerance in adults: WHO Ad Hoc Diabetes Reporting Group. Diabetes Care 1993; 16: 157–77

    PubMed  Article  CAS  Google Scholar 

  2. King H, Aubert RE, Herman WH. Global burden of diabetes, 1995-2025: prevalence, numerical estimates, and projections. Diabetes Care 1998; 21: 1414–31

    PubMed  Article  CAS  Google Scholar 

  3. The DCCT Research Group. Reliability and validity of a diabetes quality-of-life measure for the diabetes control and complications trial (DCCT). Diabetes Care 1988; 11: 725–32

    Article  Google Scholar 

  4. Wild S, Roglic G, Green A, et al. Global prevalence of diabetes: estimates for the year 2000 and projections for 2030. Diabetes Care 2004; 27: 1047–53

    PubMed  Article  Google Scholar 

  5. Amos AF, McCarty DJ, Zimmet P. The rising global burden of diabetes and its complications: estimates and projections to the year 2010. Diabet Med 1997; 14: 1–85

    Article  Google Scholar 

  6. International Diabetes Federation. Diabetes atlas 2000. Brussels: International Diabetes Federation, 2000

    Google Scholar 

  7. Pan XR, Yang WY, Li GW, et al. Prevalence of diabetes and its risk factors in China, 1994: National Diabetes Prevention and Control Cooperative Group. Diabetes Care 1997; 20: 1664–9

    PubMed  Article  CAS  Google Scholar 

  8. Fong DS, Aiello L, Gardner TW, American Diabetes Association, et al. Retinopathy in diabetes. Diabetes Care 2004; 27Suppl. 1: S84–7

    PubMed  Article  Google Scholar 

  9. Dandona L, Dandona R, Naduvilath TJ, et al. Population based assessment of diabetic retinopathy in an urban population in southern India. Br J Ophthalmol 1999; 83: 937–40

    PubMed  Article  CAS  Google Scholar 

  10. Beaglehole R, Bonita R, Kjellstrom T, editors. Basic epidemiology. Geneva: World Health Organization, 1993

    Google Scholar 

  11. WrongDiagnosis.Com. Statistics by country for diabetic retinopathy: incidence (annual) of diabetes retinopathy [online]. Available from URL: http://www.wrongdiagnosis.com/d/diabetic_retinopathy/stats-country.htm [Accessed 2008 May 12]

  12. Satman I, Yilmaz T, Sengul A, et al. Population-based study of diabetes and risk characteristics in Turkey: results of the Turkish diabetes epidemiology study (TURDEP). Diabetes Care 2002; 25: 1551–6

    PubMed  Article  Google Scholar 

  13. Turkish Ministry of Health. Turkey: population health survey 1993. Ankara: Hacettepe University, Institute for Population Studies and Macro International Inc., 1994

    Google Scholar 

  14. Bagriaçik N, Ipbiiker A, Ilkova H. Diabetes in Turkey. IDF Bull 1990; 35: 3

    Google Scholar 

  15. Kelestimur F, Çetin M, Pasaoglu H, et al. The prevalence and identification of risk factors for type 2 diabetes mellitus and impaired glucose tolerance in Kayseri, Central Anatolia, Turkey. Acta Diabetol 1999; 36: 85–91

    PubMed  Article  CAS  Google Scholar 

  16. Şengul AM, Salman F, Sargin M, et al. Determinants of the quality of life of patients with type 1 diabetes in Turkey [abstract]. European Association for Study of Diabetes (EASD) 35th Annual Meeting; 1999 Sep 28–Oct 2; Brussels: A37-134

  17. Yildirim A. Health-related quality of social life. Gulhane Med J 2002; 44: 480–5

    Google Scholar 

  18. Toprak AB, Eser E, Guler C, et al. Cross-validation of the Turkish version of the 25-item National Eye Institute Visual Functioning Questionnaire (NEI-VFQ 25). Ophthalmic Epidemiol 2005; 12: 259–69

    PubMed  Article  Google Scholar 

  19. Andersen RM, Rice TH, Kominski GF. Changing the US health care system. San Francisco (CA): Jossey-Bass, 1996

    Google Scholar 

  20. Mangione CM, Lee PP, Gutierrez PR, et al. Development of the 25-item National Eye Institute Visual Function Questionnaire (VFQ-25). Arch Ophthal 2001; 119: 1050–8

    PubMed  CAS  Google Scholar 

  21. Nordmann JP, Viala M, Sullivan K, et al. Psychometric validation of the National Eye Institute Visual Function Questionnaire-25 (NEI VFQ-25) French version. Pharmacoeconomics 2004; 22(3): 197–206

    PubMed  Article  Google Scholar 

  22. Rossi GCM, Milano G, Tinelli C. The Italian version of the 25-item National Eye Institute Visual Function Questionnaire: translation, validity, and reliability. J Glaucoma 2003; 12(3): 213–20

    PubMed  Article  Google Scholar 

  23. Broman AT, Munoz B, West SK, et al. Psychometric properties of the 25-item NEI-VFQ in a Hispanic population: Proyecto VER. Invest Ophthalmol Vis Sci 2001; 42: 606–13

    PubMed  CAS  Google Scholar 

  24. Akinci F, Yildirim A, Ogutmen B, et al. Translation, cultural adaptation, initial reliability and validation of Turkish 15D’s version: a Generic Health-Related Quality of Life (HRQoL) Instrument. Eval Health Prof 2005; 28: 53–66

    PubMed  Article  Google Scholar 

  25. Ware JE, Sherbourne CD. The MOS 36-Item Short-Form Health Survey (SF-36): I. Conceptual framework and item selection. Med Care 1992; 30: 473–83

    PubMed  Article  Google Scholar 

  26. Ware, JE. SF-36® Health survey update [online]. Available from URL: http://www.sf-36.org/tools/sf36.shtml#TRANS [Accessed 2005 Nov 15]

  27. Koçyigit H, Aydemir Ö, Fişek G, et al. The reliability and validity of the Turkish version of the Short Form 36 (SF-36) [in Turkish]. Ilac ve Tedavi Dergisi 1999; 12: 102–6

    Google Scholar 

  28. Brislin RW. Back translation for cross-cultural research. J Cross Cult Psychol 1970; 1: 185–216

    Article  Google Scholar 

  29. Kucukdeveci AA, McKenna SP, Kutlay S, et al. The development and psychometric assessment of the Turkish version of the Nottingham Health Profile. Int J Rehabil Res 2000; 23: 31–8

    PubMed  Article  CAS  Google Scholar 

  30. Sintonen H. The 15D instrument of health-related quality of life: properties and applications. Ann Med 2001; 33: 328–36

    PubMed  Article  CAS  Google Scholar 

  31. Jampel HD, Schwartz A, Pollack I, et al. Glaucoma patients’ assessment of their visual function and quality of life. J Glaucoma 2002; 11: 154–63

    PubMed  Article  Google Scholar 

  32. Brown MM, Brown GC, Sharma S, et al. Quality of life with visual acuity loss from diabetic retinopathy and age-related macular degeneration. Arch Ophthal 2002; 120: 481–4

    PubMed  Article  Google Scholar 

  33. Sharma S, Oliver-Fernandez A, Liu W, et al. The impact of diabetic retinopathy on health-related quality of life. Curr Opin Ophthalmol 2005; 16: 155–9

    PubMed  Article  Google Scholar 

  34. Yanoff M, Duker SJ. Vascular disorders: diabetic retinopathy. In: Benson FW, editor. Ophthalmology. London: Mosby International, 1999: 90–125

    Google Scholar 

  35. Labiris G, Katsanos A, Fanariotis M, et al. Psychometric properties of the Greek version of the NEI-VFQ 25. BMC Ophthalmol 2008; 8: 4

    PubMed  Article  Google Scholar 

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Acknowledgments

No sources of funding were used to assist in the preparation of this study. The authors have no conflicts of interest that are directly relevant to the content of this study.

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  1. Department of Health Policy and Administration, Washington State University, PO Box 1495, Spokane, Washington, 99210-1495, USA

    Akinci Fevzi

  2. The Section of the Basic Health Sciences, Marmara University Health Education Faculty, Cevizli, Kartal, Istanbul, Turkey

    Yildirim Aysegul

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  1. Akinci Fevzi
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  2. Yildirim Aysegul
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Correspondence to Akinci Fevzi.

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Fevzi, A., Aysegul, Y. Psychometric Performance of the National Eye Institute 25-Item Visual Function Questionnaire. Patient-Patient-Centered-Outcome-Res 1, 115–125 (2008). https://doi.org/10.2165/01312067-200801020-00007

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Keywords

  • Diabetic Retinopathy
  • Turkish Version
  • Greek Version
  • Psychometric Performance
  • Diabetic Retinopathy Patient