VISUAL IMPAIRMENT AND BLINDNESS 121 TABLE 4-6. (NBS 1981) VISUAL IMPAIRMENT BY WHO CATEGORIES (SHORT FORM) Visual Acuity Sample N Population Estimates Percentage in Population Category 0 1-2 3-5 Not impaired Low vision Blind 38,478 738 335 23,680,142 259,888 117,623 97.31% 1.85 0.84 Source: PFRANY .001 AN.1 an estimated 377,511 persons have some degree of bilateral visual impairment. Table 4- 7 shows the distribution of the population according to whether persons are sighted in both eyes, blind in one eye, or blind in both eyes. Nearly 1,000 (996) of the 39,887 persons examined in the survey were blind in one or both eyes, an estimated 351,235 persons for all Nepal. Of these, an estimated 233,612 are unilaterally blind while 117,623 are blind in both eyes. This represents a prevalence approximately 16 times greater than -is found in the United States and is an enormous burden of blindness in a country as small as Nepal. The magnitude of the problem of blindness is discussed in Section 4.4. TABLE 4-7. DISTRIBUTION, ESTIMATED NUMBER OF CASES, AND PREV- ALENCE OF UNILATERAL AND BILATERAL BLINDNESS (NBS 1981) Estimated Number of Cases Percentage of Nepal's Total Sample N Sighted both eyes Blind in one eye Blind in both eyes Subtotal Missing 38,547 661 335 39,543 344 13,703,500 233,612 117,623 14,054,735 118,346 117.5% 1.7 0.8 100.0 NA Total 39,887 14,173,081 100.0 Source: FR4.002 AN.X 4.3.2 Demographic Characteristics Age: In Nepal, as elsewhere, the major determinant of blindness prevalence is age. Table 4-8 shows the prevalence, estimated num-
