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4: Wearers, Prices, and Sources of Payment 4 . Wearers, Prices, and Sources of Payment WEARERS OF CONTACT LENSES “Disorders of refraction and accommodation, ” Table 5.—Contact Lens Wearers, Percent according to the U.S. Public Health Service, of Population, by Sex and Age, ranked 14th among the 20 most common reasons 1965-66, 1971, and 1979.80 for visiting a physician but accounted for only 1.4 Percent of population 3 percent of all visits to non-Federal, office-based years and over wearing physicians in 1981 (52). Unlike other diagnostic contact lenses categories, however, refractive examinations and Sex and age group 1965-66 1971 1979-80 Both sexes: corrective-lens prescribing and fitting can be ob- All ages, 3 and over. 1.0 2.1 4.5 tained from eye-care professionals other than phy- 3-16 . 0.3 0.6 1.0 sicians (i. e., optometrists and, in some States, op- 17-24 . 3.7 6.6 9.4 ticians). In fact, optometrists represent about 25-44 . 1.3 3.0 7.7 45-54 . 0.4 0.7 2.1 two-thirds of those professionals legally permitted 55-64 . 0.3 0.7 1.6 to examine eyes and prescribe corrective lenses, 65 and over . — 0.7 4.3 and they prescribe approximately three-fourths Male: 60 All ages, 3 and over. , . 0.6 1.2 2.8 of all corrective lenses and percent of all con- 3-16 . — 0.3 0.6 tact lenses (5,12). If all such eye care were pro- 17-24 . 2.0 3.4 5.3 vided by ophthalmologists, refractive disorders 25-44 . 0.9 1.8 4.4 45-54 . 0.3 0.5 1.4 would rank among the top three reasons for 55-64 . 0.7 1.4 visiting a physician, either closely following 65 and over . 0.7 4.6 hypertension and normal pregnancy or leading Female: them, depending on the adjustment factor cho- All ages, 3 and over. 1.3 2.9 6.2 3-16 . 0.4 0.9 1.5 sen. Accordingly, it is not surprising that over half 17-24 . 5.2 9.5 13.3 of the population 3 years old and above wear cor- 25-44 . 1.7 4.2 10.7 rective lenses and that about 15 million persons 45-54 . 0.5 0.9 2.7 55-64 . — 0.6 1.9 wear contact lenses. 65 and over . — 0.7 4.0 SOURCES: 1965-66: U.S. Department of Health, Education, and Welfare, In table 5, data from three National Health Characteristics of Persons With Corrective Lenses, United States Survey studies of corrective lens wearers are July 1965-June 1966, Vital and Health Statistics, series 10, No. 53, prepared by M. M. Hannaford, DHEW publication No. (PHS) 1000 presented. These data, for 1965-66, 1971, and (Washington, DC: US. Government Printing Office, June 1969) 1971: U.S. Department of Health, Education, and Welfare, Characteristics 1979-80, show some interesting patterns and of Persons With Corrective Lenses, United States: 1971, Vital and trends among users. In each of the study periods, Health Statistics, series 10, No. 93, prepared by M. H. Wilder, DHEW publication no. (HRA) 75-1520, Washington, DC, 1974. 1979-60: R. Hol- contact lens wearing was at least twice as preva- Iander, U.S. Department of Health and Human Services, Public Health lent among females, overall, as among males. Fur- Service, Rockville, MD, personal communication, June 30, 1983. ther, lens wearing is most common among young adults, tapering to low levels at middle age and stantial validity, but the pattern presently is beyond. This pattern is almost totally the opposite changing in substantial ways and will be con- of the age-related frequency of use of eyeglasses. siderably different in the future. The current (However, in 1979-80, lens wearing in the 65 and changes, particularly the increasing use of con- over group, both males and females, rose sharply. ) tact lenses by older persons, are attributable to Third, over the covered period, lens wearing in- younger lens wearers’ moving through the age creased at every age level for both males and spectrum; the development of newer types of females. Thus, the general view of contact lenses bifocal and toric lenses, which relate especially as primarily a “younger female” product has sub- to the vision problems of older persons; and the 23 25-339 0 - 84 - 5 : QI, 3 — 24 ● Health Case Study 31: The Contact Lens Industry: Structure, Competition, and Public Policy growth in soft and extended-wear lenses, which as income expands, or in economists’ parlance, particularly help older persons, whose eyes are with a positive income elasticity of demand. less accommodating to contact lenses than are Data from the National Center for Health Serv- those of younger persons. Further, differences in ices Research’s National Health Expenditures the rates of lens usage by women and men are nar- Study (table 6) shed a bit more light on the in- rowing, and in new fits the differences will soon come elasticity of demand for contact lenses. (The be eliminated. Accordingly, the lens market will income elasticity of demand measures the relation- no longer be dominated by the young adult female ship between changes in income and the resulting wearer; the traditional patient base will expand changes in the number of units purchased. ) If we widely; and all groups except perhaps children will were to assume average incomes within the three become important users. classes to be $6,000, $18,000, and $30,000 respec- Although as large a part of the population with tively, with all other characteristics showing simi- vision correction suffers from presbyopia as from lar patterns among income classes, then the in- single-vision problems, lens wearing is much more come elasticity would be approximately 0.13 to prevalent among the latter group. As lenses for 0.27, which is a plausible range of estimation. (An all users improve, the greatest relative growth will income elasticity of demand of 0.13 means that be for presbyopes and astigmatic, but contact a l-percent increase [decrease] in income causes lenses will continue to be prescribed most fre- a 0.13 of l-percent increase [decrease] in units quently for single-vision problems. Within the [pairs of contact lenses] purchased.) single-vision category, about 60 percent have Although no measurement or estimation is myopia, 40 percent hyperopia. In addition, the made here of the price elasticity or cross elasticity relative use of contact lenses for those with myopia of demand (defined as the effects on lens purchases runs somewhat higher than among those with of changes in the price of lenses and of changes hyperopia. Therefore, at least through the 1980s, in the price of other goods, particularly eyeglasses, the largest absolute volume of sales will continue respectively) for contact lenses, certain relation- to be for the correction of myopia, followed by ships may be suggested on the basis of recent ex- hyperopia, with presbyopic use gaining quickly perience. First, the demand for lenses seems to be and perhaps passing hyperopia before the 1980s at least somewhat sensitive to changes in the rela- have ended. tive price of lenses in that wearers of eyeglasses Additional data from the National Health Ex- frequently specify cost as one of their reasons for penditures Survey (51) show contact lens use to not switching to lenses. (Theoretically, if the de- be relatively more common in suburban than ru- mand for a product is sensitive to changes in in- ral or inner-city areas, among whites than non- come levels, it also is sensitive to price changes whites (particularly blacks and Hispanics), and of that product. The connection between the also to be positively associated with the educa- two is the so-called “income effect” of the price tional level of the family head. All of these cor- change. ) relations are explainable in terms of the higher in- come levels among suburban residents, whites, and the more educated. (Other features in the pat- tern of contact lens use show that lenses are more Table 6.—Purchase or Repair of Contact Lenses often worn by white-collar and service workers per 1,000 Population at Different Family than by blue-collar or farm workers. These dif- income Levels, 1977 ferences may also be explainable in part by in- Persons with purchase or repair come differentials, but probably more so by the Family income of contact lenses greater proportion of women employed in the Less than $12,000 . 0.9 white-collar and service sectors, and perhaps also $12,000 to $19,999 . 1.1 $20,000 or more. 1.4 by the actual physical conditions of each type of SOURCE: U.S. Department of Health and Human Services, Public Health Service, work. ) In other words, contact lenses are a “nor- National Center for Health Statistics, 1981 Summary: National Ambu- latory Medical Care Survey, NCHS Advance data, prepared by L. Law- mal” economic good, with purchases expanding rence and T. McLemore, No. 66, Hyattsville, MD, Mar. 16 1963. Ch. 4—Wearers, Prices, and Sources of Payment ● 25 Second, through time, new developments in the safety advantage of contact lenses in activi- both contact lenses and eyeglasses may have nar- ties where spectacle frames and lenses have posed rowed the qualitative differences between the two a problem; new eyeglass lenses of plastic on the types of corrective lenses, leaving the remaining inside, for safety, and glass on the outside, for differences, including price, as relatively more im- durability, have just been introduced. portant bases of choice than previously was the Thus, although the price level of corrective case.
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