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Evaluating Whether Sight Is the Most Valued Sense Research JAMA Ophthalmology | Brief Report Evaluating Whether Sight Is the Most Valued Sense Jamie Enoch, MSc; Leanne McDonald, MSc; Lee Jones, PhD; Pete R. Jones, PhD; David P. Crabb, PhD Supplemental content IMPORTANCE Sight is often considered to be the sense most valued by the general public, but there are limited empirical data to support this. This study provides empirical evidence for frequent assertions made by practitioners, researchers, and funding agencies that sight is the most valued sense. OBJECTIVE To determine which senses are rated most valuable by the general public and quantify attitudes toward sight and hearing loss in particular. DESIGN, SETTING, AND PARTICIPANTS This cross-sectional web-based survey was conducted from March to April 2016 through a market research platform and captured a heterogeneous sample of 250 UK adults ages 22 to 80 years recruited in March 2016. The data were analyzed from October to December 2018. MAIN OUTCOMES AND MEASURES Participants were first asked to rank the 5 traditional senses (sight, hearing, touch, smell, and taste) plus 3 other senses (balance, temperature, and pain) in order of most valuable (8) to least valuable (1). Next, the fear of losing sight and hearing was investigated using a time tradeoff exercise. Participants chose between 10 years without sight/hearing vs varying amounts of perfect health (from 0-10 years). RESULTS Of 250 participants, 141 (56.4%) were women and the mean (SD) age was 49.5 (14.6) years. Two hundred twenty participants (88%) ranked sight as their most valuable sense (mean [SD] rating, 7.8 [0.9]; 95% CI, 7.6-7.9). Hearing was ranked second (mean [SD] rating, 6.2 [1.3]; 95% CI 6.1-6.4) and balance third (mean [SD] rating, 4.9 [1.7]; 95% CI, 4.7-5.1). All 3 were ranked above the traditional senses of touch, taste, and smell (F7 = 928.4; P < .001). The time tradeoff exercise indicated that, on average, participants preferred 4.6 years (95% CI, 4.2-5.0) of perfect health over 10 years without sight and 6.8 years (95% CI, 6.5-7.2) of perfect health over 10 years without hearing (mean difference between sight and hearing, 2.2 years; P < .001). Author Affiliations: Department of CONCLUSIONS AND RELEVANCE In a cross-sectional survey of UK adults from the general Optometry & Visual Sciences, School public, sight was the most valued sense, followed by hearing. These results suggest that of Health Sciences, City, University of people would on average choose 4.6 years of perfect health over 10 years of life with London, London, England. complete sight loss, although how this generalizes to other parts of the world is unknown. Corresponding Author: David P. Crabb, PhD, Department of Optometry and Visual Sciences, City, JAMA Ophthalmol. doi:10.1001/jamaophthalmol.2019.3537 University of London, Northampton Published online October 3, 2019. Square, London, London EC1V 0HB, England ([email protected]). esearch in the United States has shown that members public and quantified attitudes toward sight and hearing loss of the public rate sight loss as a greater concern than in particular using a time tradeoff (TTO) exercise. R loss of memory, loss of speech/hearing, or chronic health conditions, such as HIV/AIDS and heart disease.1 Simi- larly, a longitudinal clinical study with patients experiencing Methods sensory loss has shown that loss of sight and touch cause the greatest decreases in quality of life before loss of hearing, taste, This study was approved by the City, University of London and smell.2 However, to our knowledge, the relative impor- School of Health Science’s research ethics committee. Writ- tance of sight compared with other senses has not been sys- ten informed consent was obtained from all participants be- tematically investigated in the general population in a non- fore enrollment. An online survey was delivered by an inde- clinical setting. We therefore conducted a survey to determine pendent market research company, FlexMR (FlexMR Ltd), who which senses are rated most valuable by a cross-section of the was contracted by the research team specifically to dissemi- jamaophthalmology.com (Reprinted) JAMA Ophthalmology Published online October 3, 2019 E1 © 2019 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ by a Universita Torino User on 10/28/2019 Research Brief Report Evaluating Whether Sight Is the Most Valued Sense nate the survey and collate responses. FlexMR sampled 250 UK-based adults in March 2016 (median [range] age: 50 years Key Points [22-80 years]; 141 women [56.4%]). The participants were Question Which sense is most valued by the general public in the selected from a pool of UK-based individuals who had United Kingdom? previously registered to receive survey invitations from Findings This cross-sectional online survey found that sight is the FlexMR and were entered into a prize draw as compensation. most valued sense, followed by hearing. On average, participants Participants’ sociodemographic characteristics were col- would choose 4.6 years of life in perfect health over 10 years of life lected (eTable in the Supplement). The survey was open to with complete sight loss, and members of the public valued individuals who may have had a sensory impairment them- balance above traditionally recognized senses, such as touch, selves or within their family. taste, and smell. This study adopted a broader definition of senses than Meaning This study supports frequent assertions made by the 5 “traditional” senses defined by Aristotle, also including practitioners, researchers, and funding agencies that sight is the balance (equilibrioception), pain (nociception), and tem- most valued sense among the general population of the United perature (thermoception). Participants were first asked to Kingdom. rank 8 senses (sight, hearing, touch, smell, taste, balance, temperature, and pain) in order of most valuable (8) to least valuable (1). Next, the fear of losing sight and hearing 4.9 [1.7]; 95% CI, 4.7-5.1), above the 3 traditional senses of touch was investigated using a TTO exercise.3 Participants chose (mean [SD] rating, 4.5 [1.7]), taste (mean [SD] rating, 3.8 [1.8]), between 10 years without sight/hearing (life A) vs varying and smell (mean [SD] rating, 3.4 [1.7]) (Wilcoxon signed rank test amounts of perfect health in 1-year decrements from 10 to 0 for pairwise comparison between balance and touch, W = 36 333; years (life B). This allowed for the calculation of the number P= .04 after Bonferroni correction). of years without sight or hearing that a participant would In the TTO exercise, participants, on average, chose 4.6 trade for perfect health over a 10-year period. Differences in years (95% CI, 4.2-5.0) of life in perfect health over 10 years years traded between groups were then analyzed using of life with complete sight loss and 6.8 years (95% CI, 6.5-7.2) Wilcoxon rank sum and Kruskal-Wallis tests. Statistical of life in perfect health as an alternative to 10 years of life with analyses were performed using R, version 3.5 (R Founda- complete hearing loss. This means that over a 10-year period, tion), and statistical significance was set at α = .05. participants were prepared to sacrifice a mean (SD) 5.4 (3.1) years without sight (95% CI, 5.0-5.8) and 3.2 (2.9) years with- out hearing (95% CI, 2.8–3.5) to remain in perfect health (mean Results difference between sight and hearing, 2.2 years; P < .001). Thirty-eight participants (15%) chose death (0 years of life B) As shown in Figure 1, 220 participants (88%; 95% CI, 82%-94%) over 10 years with complete sight loss and 15 participants (6%) ranked sight as their most valuable sense (mean [SD] rank, 7.8 chose death over 10 years with complete hearing loss (Figure 2). [0.9]; 95% CI, 7.6-7.9). Hearing was ranked as the second-most Men were willing to sacrifice almost 1 year more without valuable sense (mean [SD] rank, 6.2 [1.3]; 95% CI, 6.1-6.4) but was sight than women in exchange for perfect health (mean dif- rated as significantly less valuable than vision (P < .001). Balance ference, 0.94 years; P = .03) (Figure 2). There were no statis- was ranked as the third-most valuable sense (mean [SD] rank, tically significant differences in the number of years without Figure 1. Dot Plot Showing Rankings of the 8 Senses Under Investigation SightHearing Balance Touch Taste Smell Pain Temperature 8 7 6 5 4 3 Rank, Least to Most Valuable Sense Rank, Least to Most Valuable 2 1 E2 JAMA Ophthalmology Published online October 3, 2019 (Reprinted) jamaophthalmology.com © 2019 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ by a Universita Torino User on 10/28/2019 Evaluating Whether Sight Is the Most Valued Sense Brief Report Research For hearing, people with a family history of sensory impair- Figure 2. Responses to the Time Tradeoff (TTO) Exercise ment would give up significantly fewer years without hear- A All participants ing than those with no family history of sensory impairment 100 (mean difference, −1.46 years; P < .01). Participants with Hearing chronic conditions would give up fewer years without hear- Sight ing than those with no chronic conditions (mean difference, 75 −0.56 years; P = .04). There were no statistically significant dif- ferences in the number of years without hearing that partici- 50 pants would give up based on age (mean [SD] for age 22-40 years, 3.3 [3.0]; mean [SD] for age 41-60 years, 2.9 [2.9]; mean [SD] for age 61-80 years, 3.3 [2.8]; Kruskal Wallis test, H2 = 1.54; Sensory Impairment, % 25 Preferred Over 10 y With Preferred Over P = .46) or sex (mean [SD] for women, 3.1 [2.9]; mean [SD] for men, 3.3 [2.9]; Wilcoxon rank sum test, W =7247;P = .44).
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