Document Type : Original Article
Authors
1 Center for Healthcare Data Modeling, Departments of Biostatistics and Epidemiology, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
2 Department of Ophthalmology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Abstract
BACKGROUND: Visual impairment (VI) is one of the major public health problems that cause
suffering, disability, loss of productivity, and reduced quality of life (QoL). This study aimed to evaluate
the health‑related QoL (HRQoL) among adults with visual problems in 2021.
MATERIALS AND METHODS: This analytical cross‑sectional study was conducted on 300 patients with
VIs referring to ophthalmology centers in Yazd, Iran. Data were collected through face‑to‑face interviews
using EQ‑5D, visual analog scale (VAS), and demographic information questionnaires. The results were
analyzed using independent sample t‑test, one-way analysis of variance, Pearson correlation coefficient,
and adjusted limited dependent variable mixture model (ALDVMM) model by STATA, and SPSS.
RESULTS: The mean and standard deviation of EQ‑5D‑5 L index and EQ‑VAS score in the studied
patients were 0.68 ± 0.25 and 72.46 ± 19.36, respectively. Most problems at unable/extreme level
were related to the mobility dimension (12%) and the usual activities dimension (9%). Factors related
to HRQoL scores using ALDVMM model showed that divorced or widow marital status, age over 50,
having strabismus, and acuter visual problems had significant negative effects on EQ‑5D‑5 L index
values (P < 0.05).
CONCLUSIONS: The results showed that HRQoL was moderate in patients with VIs and reduced in
patients with high disease severity, old age, lack of a spouse, retirement, and nonuniversity education.
As a result, socioeconomic and demographic characteristics were required to be considered in visual
health policies.
Keywords
1. Bourne RR, Flaxman SR, Braithwaite T, Cicinelli MV, Das A,
Jonas JB, et al. Magnitude, temporal trends, and projections of
the global prevalence of blindness and distance and near vision
impairment: A systematic review and meta‑analysis. Lancet Glob
Health 2017;5:e888‑97.
2. Fricke TR, Tahhan N, Resnikoff S, Papas E, Burnett A, Ho SM,
et al. Global prevalence of presbyopia and vision impairment from
uncorrected presbyopia: Systematic review, meta‑analysis, and
modelling. Ophthalmology 2018;125:1492‑9.
3. Yip JL, Luben R, Hayat S, Khawaja AP, Broadway DC,
Wareham N, et al. Area deprivation, individual socioeconomic
status and low vision in the EPIC‑Norfolk eye study. J Epidemiol
Community Health 2014;68:204‑10.
4. Adigun K, Oluleye TS, Ladipo MM, Olowookere SA. Quality of
life in patients with visual impairment in Ibadan: A clinical study
in primary care. J Multidiscip Healthc 2014;7:173‑8.
5. Pérès K, Matharan F, Daien V, Nael V, Edjolo A,
Bourdel‑Marchasson I 1st, et al. Visual loss and subsequent
activity limitations in the elderly: The French three‑city cohort.
Am J Public Health 2017;107:564‑9.
6. Teutsch SM, McCoy M, Woodbury R, Welp A. Making Eye
Health a Population Health Imperative: Vision for Tomorrow.
Washington (DC): National Academies Press (US); 2016.
7. Pardhan S, Latham K, Tabrett D, Timmis MA. Objective analysis
of performance of activities of daily living in people with central
field loss. Invest Ophthalmol Vis Sci 2015;56:7169‑78.
8. Brown RL, Barrett AE. Visual impairment and quality of life
among older adults: An examination of explanations for the
relationship. J Gerontol B Psychol Sci Soc Sci 2011;66:364‑73.
9. Grow SJ, Towers A, Yeung P, Alpass F, Stephens C. The
relationship between loneliness and perceived quality of life
among older persons with visual impairments. J Vis Impair Blind
2015;109:487‑99.
10. Hassell JB, Lamoureux EL, Keeffe JE. Impact of age related
macular degeneration on quality of life. Br J Ophthalmol
2006;90:593‑6.
11. Purola PK, Nättinen JE, Ojamo MU, Koskinen SV, Rissanen HA,
Sainio PR, et al. Prevalence and 11‑year incidence of common eye
diseases and their relation to health‑related quality of life, mental
health, and visual impairment. Qual Life Res 2021;30:2311‑27.
12. Haegele JA, Zhu X. Physical activity, self‑efficacy and
health‑related quality of life among adults with visual
impairments. Disabil Rehabil 2021;43:530‑6.
13. Duenas M, Saaddine J. Improving the Nation’s Vision Health;
A Coordinated Public Health Approach. National Center for
Chronic Disease Prevention and Health Promotion (U.S.), Division
of Diabetes Translation, United States, 2007.
14. Kymes SM, Lee BS. Preference‑based quality of life measures in
people with visual impairment. Optom Vis Sci 2007;84:809‑16.
15. Skevington SM, Lotfy M, O’Connell KA; WHOQOL Group.
The World Health Organization’s WHOQOL‑BREF quality
of life assessment: Psychometric properties and results of the
international field trial. A report from the WHOQOL group. Qual
Life Res 2004;13:299‑310.
16. Ebrahim S. Clinical and public health perspectives and
applications of health‑related quality of life measurement. Soc
Sci Med 1995;41:1383‑94.
17. Karyani AK, Matin BK, Gebru AA, Dizaj JY, Rezaei S. Life and
health satisfaction and their association toward health‑related
quality of life, body mass index and chronic diseases in Iran.
J Educ Health Promot 2019;8:71.
18. Ferrans CE. Definitions and conceptual models of quality of life.
In: Outcomes Assessment in Cancer: Measures, Methods, and
Applications. Cambridge University Press, United States; 2005.
p. 14‑30.
19. Fukuda S, Okamoto F, Yuasa M, Kunikata T, Okamoto Y,
Hiraoka T, et al. Vision‑related quality of life and visual function
in patients undergoing vitrectomy, gas tamponade and cataract
surgery for macular hole. Br J Ophthalmol 2009;93:1595‑9.
20. Lin JC, Yu JH. Assessment of quality of life among Taiwanese
patients with visual impairment. J Formos Med Assoc
2012;111:572‑9.
21. Varma R, Wu J, Chong K, Azen SP, Hays RD; Los Angeles Latino
Eye Study Group. Impact of severity and bilaterality of visual
impairment on health‑related quality of life. Ophthalmology
2006;113:1846‑53.
22. Brazier J, Ara R, Rowen D, Chevrou‑Severac H. A review of
generic preference‑based measures for use in cost‑effectiveness
models. Pharmacoeconomics 2017;35:21‑31.
23. Weinstein MC, Stason WB. Foundations of cost‑effectiveness
analysis for health and medical practices. N Engl J Med
1977;296:716‑21.
24. Malkin AG, Goldstein JE, Massof RW. Multivariable regression
model of the EuroQol 5‑dimension questionnaire in patients
seeking outpatient low vision rehabilitation. Ophthalmic
Epidemiol 2017;24:174‑80.
25. Brooks R. EuroQol: The current state of play. Health Policy
1996;37:53‑72.
26. Herdman M, Gudex C, Lloyd A, Janssen M, Kind P, Parkin D,
et al. Development and preliminary testing of the new five‑level
version of EQ‑5D (EQ‑5D‑5L). Qual Life Res 2011;20:1727‑36.
27. Linde L, Sørensen J, Ostergaard M, Hørslev‑Petersen K,
Hetland ML. Health‑related quality of life: Validity, reliability,
and responsiveness of SF‑36, 15D, EQ‑5D RAQoL, and HAQ in
patients with rheumatoid arthritis. J Rheumatol 2008;35:1528‑37.
28. Johnson JA, Coons SJ, Ergo A, Szava‑Kovats G. Valuation
of EuroQOL (EQ‑5D) health states in an adult US sample.
Pharmacoeconomics 1998;13:421‑33.
29. van Hout B, Janssen MF, Feng YS, Kohlmann T, Busschbach J,
Golicki D, et al. Interim scoring for the EQ‑5D‑5L: Mapping the
EQ‑5D‑5L to EQ‑5D‑3L value sets. Value Health 2012;15:708‑15.
30. EuroQol Research Foundation: EQ‑5D‑5L | about. Available from:
https://euroq ol.org/eq‑5d‑instruments/eq‑5d‑5l‑about/. [Last
accessed on 2021 November].
31. Mirzaie M, Nafisi N. An Investigation of Health Related Quality
of Life (HRQOL) in adults of the city of Tehran with emphasis
on self‑reported health. J Soc Probl Iran 2016;7:55‑76.
32. Tielsch JM, Sommer A, Witt K, Katz J, Royall RM. Blindness
and visual impairment in an American urban population. The
Baltimore eye survey. Arch Ophthalmol 1990;108:286‑90.
33. Ameri H, Safari H, Yousefi M, Bagheri Faradonbeh S, Goudarzi R,
Soofi M. Interim value set for the EQ‑5D‑5L in Iran using the
Crosswalk method. Med J Islam Repub Iran 2020;34:121.
34. Brazier JE, Yang Y, Tsuchiya A, Rowen DL. A review of studies
mapping (or cross walking) non‑preference based measures of
health to generic preference‑based measures. Eur J Health Econ
2010;11:215‑25.
35. Alava MH, Wailoo A. Fitting adjusted limited dependent variable
mixture models to EQ‑5D. Stata J 2015;15:737‑50.
36. Bongo PP, Dziruni G, Muzenda‑Mudavanhu C. The effectiveness
of community‑based rehabilitation as a strategy for improving
quality of life and disaster resilience for children with disability
in rural Zimbabwe. Jamba 2018;10:442.
37. Kawashima M, Hiratsuka Y, Nakano T, Tamura H, Ono K,
Murakami A, et al. The association between legal Japanese
visual impairment grades and vision‑related quality of life. Jpn J
Ophthalmol 2016;60:219‑25.
38. Chatziralli I, Mitropoulos P, Parikakis E, Niakas D, Labiris G,
editors. Risk factors for poor quality of life among patients
with age‑related macular degeneration. In: Seminars in
Ophthalmology. UK: Taylor & Francis; 2017.
39. Breheny K, Hollingworth W, Kandiyali R, Dixon P, Loose A, Craggs P, et al. Assessing the construct validity and responsiveness
of preference‑based measures (PBMs) in cataract surgery patients.
Qual Life Res 2020;29:1935‑46.
40. Elsman EB, van Rens GH, van Nispen RM. Quality of life
and participation of young adults with a visual impairment
aged 18‑25 years: Comparison with population norms. Acta
Ophthalmol 2019;97:165‑72.
41. Gyawali R, Paudel N, Adhikari P. Quality of life in Nepalese
patients with low vision and the impact of low vision services.
J Optom 2012;5:188‑95.
42. van Nispen R, van der Aa H, Timmermans F, Meijer N, Koster N,
de Blok J, et al. Reducing avoidable visual impairment in elderly
home healthcare patients by basic ophthalmologic screening. Acta
Ophthalmol 2019;97:401‑8.
43. Purola PK, Nättinen JE, Parkkari MM, Ojamo MU, Koskinen SV,
Rissanen HA, et al. Improving health‑related quality of life in
glaucoma during 11 years and its association with vision loss and
treatment of the disease. Acta Ophthalmol 2022;99 (8):1‑12. [doi:
10.1111/aos. 14883].
44. Vu HT, Keeffe JE, McCarty CA, Taylor HR. Impact of unilateral
and bilateral vision loss on quality of life. Br J Ophthalmol
2005;89:360‑3.
45. Asgari S, Nedjat S, Hashemi H, Shahnazi A, Fotouhi A. Quality
of life in the group of patients with chronic eye disease. Iran J
Epidemiol 2012;7:43‑8.
46. Esquinas C, Ramon MA, Nuñez A, Molina J, Quintano JA,
Roman‑Rodríguez M, et al. Correlation between disease severity
factors and EQ‑5D utilities in chronic obstructive pulmonary
disease. Qual Life Res 2020;29:607‑17.
47. Nickels S, Schuster AK, Singer S, Wild PS, Laubert‑Reh D,
Schulz A, et al. The national eye institute 25‑item visual function
questionnaire (NEI VFQ‑25) – Reference data from the German
population‑based Gutenberg health study (GHS). Health Qual
Life Outcomes 2017;15:156.
48. Macedo AF, Ramos PL, Hernandez‑Moreno L, Cima J,
Baptista AM, Marques AP, et al. Visual and health outcomes,
measured with the activity inventory and the EQ‑5D, in visual
impairment. Acta Ophthalmol 2017;95:e783‑91.
49. Sugawara T, Hagiwara A, Hiramatsu A, Ogata K, Mitamura Y,
Yamamoto S. Relationship between peripheral visual field
loss and vision‑related quality of life in patients with retinitis
pigmentosa. Eye (Lond) 2010;24:535‑9.
50. Seo JH, Yu HG, Lee BJ. Assessment of functional vision score
and vision‑specific quality of life in individuals with retinitis
pigmentosa. Korean J Ophthalmol 2009;23:164‑8.
51. Tajvar M, Grundy E, Fletcher A. Social support and mental health
status of older people: A population‑based study in Iran‑Tehran.
Aging Ment Health 2018;22:344‑53.
52. Das S, Roy RN, Das DK, Chakraborty A, MondalR. Health‑related
quality of life of hemophilics and its possible correlates:
A perspective in health promotion and disability prevention.
J Educ Health Promot 2019;8:257.
53. Yibekal BT, Alemu DS, Anbesse DH, Alemayehu AM,
Alimaw YA. Vision‑related quality of life among adult patients
with visual impairment at University of Gondar, Northwest
Ethiopia. J Ophthalmol 2020;2020:1‑7.
54. Karyani AK, Rashidian A, Sefiddashti SE, Sari AA. Self‑reported
health‑related quality of life (HRQoL) and factors affecting
HRQoL among individuals with health insurance in Iran.
Epidemiol Health 2016;38:e2016046.
Jonas JB, et al. Magnitude, temporal trends, and projections of
the global prevalence of blindness and distance and near vision
impairment: A systematic review and meta‑analysis. Lancet Glob
Health 2017;5:e888‑97.
2. Fricke TR, Tahhan N, Resnikoff S, Papas E, Burnett A, Ho SM,
et al. Global prevalence of presbyopia and vision impairment from
uncorrected presbyopia: Systematic review, meta‑analysis, and
modelling. Ophthalmology 2018;125:1492‑9.
3. Yip JL, Luben R, Hayat S, Khawaja AP, Broadway DC,
Wareham N, et al. Area deprivation, individual socioeconomic
status and low vision in the EPIC‑Norfolk eye study. J Epidemiol
Community Health 2014;68:204‑10.
4. Adigun K, Oluleye TS, Ladipo MM, Olowookere SA. Quality of
life in patients with visual impairment in Ibadan: A clinical study
in primary care. J Multidiscip Healthc 2014;7:173‑8.
5. Pérès K, Matharan F, Daien V, Nael V, Edjolo A,
Bourdel‑Marchasson I 1st, et al. Visual loss and subsequent
activity limitations in the elderly: The French three‑city cohort.
Am J Public Health 2017;107:564‑9.
6. Teutsch SM, McCoy M, Woodbury R, Welp A. Making Eye
Health a Population Health Imperative: Vision for Tomorrow.
Washington (DC): National Academies Press (US); 2016.
7. Pardhan S, Latham K, Tabrett D, Timmis MA. Objective analysis
of performance of activities of daily living in people with central
field loss. Invest Ophthalmol Vis Sci 2015;56:7169‑78.
8. Brown RL, Barrett AE. Visual impairment and quality of life
among older adults: An examination of explanations for the
relationship. J Gerontol B Psychol Sci Soc Sci 2011;66:364‑73.
9. Grow SJ, Towers A, Yeung P, Alpass F, Stephens C. The
relationship between loneliness and perceived quality of life
among older persons with visual impairments. J Vis Impair Blind
2015;109:487‑99.
10. Hassell JB, Lamoureux EL, Keeffe JE. Impact of age related
macular degeneration on quality of life. Br J Ophthalmol
2006;90:593‑6.
11. Purola PK, Nättinen JE, Ojamo MU, Koskinen SV, Rissanen HA,
Sainio PR, et al. Prevalence and 11‑year incidence of common eye
diseases and their relation to health‑related quality of life, mental
health, and visual impairment. Qual Life Res 2021;30:2311‑27.
12. Haegele JA, Zhu X. Physical activity, self‑efficacy and
health‑related quality of life among adults with visual
impairments. Disabil Rehabil 2021;43:530‑6.
13. Duenas M, Saaddine J. Improving the Nation’s Vision Health;
A Coordinated Public Health Approach. National Center for
Chronic Disease Prevention and Health Promotion (U.S.), Division
of Diabetes Translation, United States, 2007.
14. Kymes SM, Lee BS. Preference‑based quality of life measures in
people with visual impairment. Optom Vis Sci 2007;84:809‑16.
15. Skevington SM, Lotfy M, O’Connell KA; WHOQOL Group.
The World Health Organization’s WHOQOL‑BREF quality
of life assessment: Psychometric properties and results of the
international field trial. A report from the WHOQOL group. Qual
Life Res 2004;13:299‑310.
16. Ebrahim S. Clinical and public health perspectives and
applications of health‑related quality of life measurement. Soc
Sci Med 1995;41:1383‑94.
17. Karyani AK, Matin BK, Gebru AA, Dizaj JY, Rezaei S. Life and
health satisfaction and their association toward health‑related
quality of life, body mass index and chronic diseases in Iran.
J Educ Health Promot 2019;8:71.
18. Ferrans CE. Definitions and conceptual models of quality of life.
In: Outcomes Assessment in Cancer: Measures, Methods, and
Applications. Cambridge University Press, United States; 2005.
p. 14‑30.
19. Fukuda S, Okamoto F, Yuasa M, Kunikata T, Okamoto Y,
Hiraoka T, et al. Vision‑related quality of life and visual function
in patients undergoing vitrectomy, gas tamponade and cataract
surgery for macular hole. Br J Ophthalmol 2009;93:1595‑9.
20. Lin JC, Yu JH. Assessment of quality of life among Taiwanese
patients with visual impairment. J Formos Med Assoc
2012;111:572‑9.
21. Varma R, Wu J, Chong K, Azen SP, Hays RD; Los Angeles Latino
Eye Study Group. Impact of severity and bilaterality of visual
impairment on health‑related quality of life. Ophthalmology
2006;113:1846‑53.
22. Brazier J, Ara R, Rowen D, Chevrou‑Severac H. A review of
generic preference‑based measures for use in cost‑effectiveness
models. Pharmacoeconomics 2017;35:21‑31.
23. Weinstein MC, Stason WB. Foundations of cost‑effectiveness
analysis for health and medical practices. N Engl J Med
1977;296:716‑21.
24. Malkin AG, Goldstein JE, Massof RW. Multivariable regression
model of the EuroQol 5‑dimension questionnaire in patients
seeking outpatient low vision rehabilitation. Ophthalmic
Epidemiol 2017;24:174‑80.
25. Brooks R. EuroQol: The current state of play. Health Policy
1996;37:53‑72.
26. Herdman M, Gudex C, Lloyd A, Janssen M, Kind P, Parkin D,
et al. Development and preliminary testing of the new five‑level
version of EQ‑5D (EQ‑5D‑5L). Qual Life Res 2011;20:1727‑36.
27. Linde L, Sørensen J, Ostergaard M, Hørslev‑Petersen K,
Hetland ML. Health‑related quality of life: Validity, reliability,
and responsiveness of SF‑36, 15D, EQ‑5D RAQoL, and HAQ in
patients with rheumatoid arthritis. J Rheumatol 2008;35:1528‑37.
28. Johnson JA, Coons SJ, Ergo A, Szava‑Kovats G. Valuation
of EuroQOL (EQ‑5D) health states in an adult US sample.
Pharmacoeconomics 1998;13:421‑33.
29. van Hout B, Janssen MF, Feng YS, Kohlmann T, Busschbach J,
Golicki D, et al. Interim scoring for the EQ‑5D‑5L: Mapping the
EQ‑5D‑5L to EQ‑5D‑3L value sets. Value Health 2012;15:708‑15.
30. EuroQol Research Foundation: EQ‑5D‑5L | about. Available from:
https://euroq ol.org/eq‑5d‑instruments/eq‑5d‑5l‑about/. [Last
accessed on 2021 November].
31. Mirzaie M, Nafisi N. An Investigation of Health Related Quality
of Life (HRQOL) in adults of the city of Tehran with emphasis
on self‑reported health. J Soc Probl Iran 2016;7:55‑76.
32. Tielsch JM, Sommer A, Witt K, Katz J, Royall RM. Blindness
and visual impairment in an American urban population. The
Baltimore eye survey. Arch Ophthalmol 1990;108:286‑90.
33. Ameri H, Safari H, Yousefi M, Bagheri Faradonbeh S, Goudarzi R,
Soofi M. Interim value set for the EQ‑5D‑5L in Iran using the
Crosswalk method. Med J Islam Repub Iran 2020;34:121.
34. Brazier JE, Yang Y, Tsuchiya A, Rowen DL. A review of studies
mapping (or cross walking) non‑preference based measures of
health to generic preference‑based measures. Eur J Health Econ
2010;11:215‑25.
35. Alava MH, Wailoo A. Fitting adjusted limited dependent variable
mixture models to EQ‑5D. Stata J 2015;15:737‑50.
36. Bongo PP, Dziruni G, Muzenda‑Mudavanhu C. The effectiveness
of community‑based rehabilitation as a strategy for improving
quality of life and disaster resilience for children with disability
in rural Zimbabwe. Jamba 2018;10:442.
37. Kawashima M, Hiratsuka Y, Nakano T, Tamura H, Ono K,
Murakami A, et al. The association between legal Japanese
visual impairment grades and vision‑related quality of life. Jpn J
Ophthalmol 2016;60:219‑25.
38. Chatziralli I, Mitropoulos P, Parikakis E, Niakas D, Labiris G,
editors. Risk factors for poor quality of life among patients
with age‑related macular degeneration. In: Seminars in
Ophthalmology. UK: Taylor & Francis; 2017.
39. Breheny K, Hollingworth W, Kandiyali R, Dixon P, Loose A, Craggs P, et al. Assessing the construct validity and responsiveness
of preference‑based measures (PBMs) in cataract surgery patients.
Qual Life Res 2020;29:1935‑46.
40. Elsman EB, van Rens GH, van Nispen RM. Quality of life
and participation of young adults with a visual impairment
aged 18‑25 years: Comparison with population norms. Acta
Ophthalmol 2019;97:165‑72.
41. Gyawali R, Paudel N, Adhikari P. Quality of life in Nepalese
patients with low vision and the impact of low vision services.
J Optom 2012;5:188‑95.
42. van Nispen R, van der Aa H, Timmermans F, Meijer N, Koster N,
de Blok J, et al. Reducing avoidable visual impairment in elderly
home healthcare patients by basic ophthalmologic screening. Acta
Ophthalmol 2019;97:401‑8.
43. Purola PK, Nättinen JE, Parkkari MM, Ojamo MU, Koskinen SV,
Rissanen HA, et al. Improving health‑related quality of life in
glaucoma during 11 years and its association with vision loss and
treatment of the disease. Acta Ophthalmol 2022;99 (8):1‑12. [doi:
10.1111/aos. 14883].
44. Vu HT, Keeffe JE, McCarty CA, Taylor HR. Impact of unilateral
and bilateral vision loss on quality of life. Br J Ophthalmol
2005;89:360‑3.
45. Asgari S, Nedjat S, Hashemi H, Shahnazi A, Fotouhi A. Quality
of life in the group of patients with chronic eye disease. Iran J
Epidemiol 2012;7:43‑8.
46. Esquinas C, Ramon MA, Nuñez A, Molina J, Quintano JA,
Roman‑Rodríguez M, et al. Correlation between disease severity
factors and EQ‑5D utilities in chronic obstructive pulmonary
disease. Qual Life Res 2020;29:607‑17.
47. Nickels S, Schuster AK, Singer S, Wild PS, Laubert‑Reh D,
Schulz A, et al. The national eye institute 25‑item visual function
questionnaire (NEI VFQ‑25) – Reference data from the German
population‑based Gutenberg health study (GHS). Health Qual
Life Outcomes 2017;15:156.
48. Macedo AF, Ramos PL, Hernandez‑Moreno L, Cima J,
Baptista AM, Marques AP, et al. Visual and health outcomes,
measured with the activity inventory and the EQ‑5D, in visual
impairment. Acta Ophthalmol 2017;95:e783‑91.
49. Sugawara T, Hagiwara A, Hiramatsu A, Ogata K, Mitamura Y,
Yamamoto S. Relationship between peripheral visual field
loss and vision‑related quality of life in patients with retinitis
pigmentosa. Eye (Lond) 2010;24:535‑9.
50. Seo JH, Yu HG, Lee BJ. Assessment of functional vision score
and vision‑specific quality of life in individuals with retinitis
pigmentosa. Korean J Ophthalmol 2009;23:164‑8.
51. Tajvar M, Grundy E, Fletcher A. Social support and mental health
status of older people: A population‑based study in Iran‑Tehran.
Aging Ment Health 2018;22:344‑53.
52. Das S, Roy RN, Das DK, Chakraborty A, MondalR. Health‑related
quality of life of hemophilics and its possible correlates:
A perspective in health promotion and disability prevention.
J Educ Health Promot 2019;8:257.
53. Yibekal BT, Alemu DS, Anbesse DH, Alemayehu AM,
Alimaw YA. Vision‑related quality of life among adult patients
with visual impairment at University of Gondar, Northwest
Ethiopia. J Ophthalmol 2020;2020:1‑7.
54. Karyani AK, Rashidian A, Sefiddashti SE, Sari AA. Self‑reported
health‑related quality of life (HRQoL) and factors affecting
HRQoL among individuals with health insurance in Iran.
Epidemiol Health 2016;38:e2016046.
)