32 The various CHé@rees generally associated with physiological senescence are known to show wide variability among individuals of the same age. and this was borne out by these data. However, some of the criteria appeared to be better indices of ag- ing than others, judging bythe degree of change and the variability of the data observed. (This statement is not based on statistical analysis.) Some‘of the better criteria appeared to be accommodation of the eyes, visual acuity, skin retraction, arcus senihs, greying of the hair, and hand strength. The measured criteria would be ex- pected to be morereliable than the estimated ones in view of the subjective element and less precise Table 20 Residual Beta Burns, 1960 Subject No. Sex 17 24 26 39 49 Age Description F 9 Slight depigmented scars, left antecubital fossae. F 19 Mottled spots of pigmentation and depigmentation, dorsum offeet. M18 Marked scarring between first and secondtoes, right foot, with binding to subcutaneoustissues. Areas of lesser involvement peripheral to this area. No evidence of chronic radiation dermanits. F 20 Slight mottled pigmentation-depigmentation with little scarring, dorsum of feet. Mottled hyperpigmented spots persist on back of neck. F 21 Black moles believed to have increased in number over right side of scoring of the latter. This appeared generallyto be the case, but the estimated vaiues for greying of the hair and arcussenilis correlated surprisingly well with age. The amount of subcutaneous fat probably influenced measurements of skin looseness, but, since loss of subcutaneous fat is somewhat age dependent, probablyin the right direction. Iris hoped that in the future statistical treat- ment of the data r avfurnish a weightingfactor for each criterion based on the degree of age-associated change and the variability of the data. Itis not always possible to run the complete battery of tests on each individual, and use of such weighting factors would tend to minimize the disparity due to the omissions. The data presented must be considered as pre- liminary in nature and to represent only a small fraction of the many varied changes associated with the aging process. Under the conditions of examinations of the Marshallese, the battery of tests employed is necessarily limited. As more ex- perience is gained, someofthe tests maybe elim1- nated and new ones added. The tests of vigorare thought to be extremely important in assessjng aging, andit is hoped that moretests of this nature may be added. At this time the data are presented to introduce an approach to a feasible means of assaving “biological age” which might beofuse in studying the possible effects of radiation on the ag- ing phenomenon in human beings. In the case of the exposed Marshallese, results of further aging surveys will be carefully evaluated, and the results neck, also several noted in left ante- a9 F 63 F 67 73 F F cubital fossa. 40 Mottled roughening and pigment variation, back of neck. 42 Mottled pigmentation,left side of neck, with slight roughening of skin. 20 Depigmented scarred areas with slight atrophyof skin over dorsum of feet, particularly at site of deeper scar on left foot. Some areas adjacent to scars snowincreased pigmentation. a 43 Pigmented moles appear to have in'y creased in number over left side of 79 neck and to lesser extent on right side at sites of rather deep beta burns. M45) Back of left ear shows depigmented scar with some binding down to cartilage. No evidence of breakdown. Figure 32. Residual scarring between first and second toes, right foot, from beta burns, 5 years post exposure (Subject 226).