Mean Length of Neck Fold in Millimeters (by Age, Sex*, and Exposure Group) TABLE 4 and Standard Deviation (by Age) Age at examinetion Group 1 M F Group 2 T M F Group 3 T M F Group 4 T M Total F T M F T $.D. 2,49 19-19 3.0 32 3.2/3.7 50 44/60 6060 60) 12 40 28] 28 40 351! 20-29 4.3 5.3 48158 60 59/58 54 5.6 5.9 60 59 5.5 5.6 5.6 1.13 30-39 167 64 65,56 62 61/60 65 6.4 5.9 65 63 6.0 64 6.3 0.95 40-49 7.4 67 69/71 69 7.00/67 69 6.8 65 69 6.8 6.9 68 69] 0.94 50-59 7.5 7.3 7.4;)7.7 7.2 74/60 7.5 7.2 7.30°67.2 723 7.30673 72.3 0.99 60-69 80 78 79/83 7656 80/79 7.6 78 7.9 $7.8 7.8 8.1 V7 78 1.00 70-79 |90 80 85190 83 85/195 88 91/100 90 93 ‘94 85 89 1,10 80-89 |— $0 90]— 100 100)/— — — 11.0 10.5 107) 110 98 9.9 1.76 6.7 68 6.7 Meon total (all ages) “Shown as M (male), F (female) and T (total). Skin fold length. The length of the skin fold expressed between the 2 arms of the pincers was estimated in millimeters. This estimate is related to skin elasticity; it is also related to the sub- cutaneous fat in the submental region, since the fat supports the skin. As the subcutaneous fat and skin elasticity decrease with age, the length of the skin fold increases. This phenomenon is manifested by the “turkey gobbler” appearance of some very old individuals. The test was performed on 609 individuals. Rather surprisingly, no differences were found by sex. The data were clearly age-related, with age accounting for approximately 50 per cent of the total variation. The data were somewhat more variable in the younger age groups. Table 4 shows the mean length of the skin fold of the total sample in relationship to age and sex and the standard deviation of each age group. Sex and exposure groups were combined. The data were subjected to analyses similar to those used in the skin re32 tractility test. Findings were negative in regard to radiation. Hair graying. The data on hair graying are considerably more complex, since they represent not only the incidence of gray hair but also a crudeestimate of the degree of graying. A truly quantitative gray hair count of the type done by Terada® would have been highly desirable for statistic analysis but was not practical. The crude grading from 0 to 3-+- added considerably more information than a simple observation of the presence or absence of gray hair could have given, but it did present problems in analysis. The data on 1,242 subjects are presented in detail in table 5; they show that the graying system detected progressive graying with advancing years. The relative deficit in younger female subjects graded as + (few gray hairs) may be an artifact of collection or may represent plucking of a few gray hairs. The latter is a relatively common practice among Japanese women. The fact that this deficit was noted mostly in GERIATRICS, JANUARY 1961