27 in Section IV. The other physical findings, which Table 15 have been carefully tabulated in the individualre- Composition of Pediatric Groups, 1972 Age at exposure, yr No. males Rongelap group ~ <10 10-19 In utero Ailingnae group <10 Unexposed group Born 1945-1954 Born 1935-1944 No.females children. The usual spectrum of infectious and 10 9 5 3 9 I 2 + 22 11 19 7 skeletal development (left hand and wrist) was initiated,*#! and systematic documentation of an- thropometric data was started. The documentation was continued during the succeeding examinations on subjects considered to be in the growth phase (generally through age 20). The datarecorded reguiarly included standing height (stature), body weight, head circumference, head width, head length, chest circumference, bi- acromial width, and calf circumference, and sporadically includedsitting height, chest width, chest depth, and buttocks circumference. (See Appendix 7.) ports for each survey, indicate no definite pattern of abnormalities that would differentiate the exposed children from the unexposed comparison . The developmentof secondary sex characteristics was qualitatively assessed according to the standard criteria generally accepted in growth studies (Greulich et al.,4? Shuttleworth#?). Such procedures included the staging of breast development in girls; estimation of the type, pattern, and amount of bodyhair(facial, pubic, axillary, etc.). and staging of the growth of penis and testes in boys. During several examinations, photo- graphic documentation was doneas partof the assessment of growth status and physique. The roentgenographic evaluation of skeletal development was donebythe inspectional technique of Greulich and Pyle,4! and the American standards were used for comparison. 2. Physical Findings The early post-exposure examinations indicated that the youngerchildren, in general, manifested more extensive and moresevere radiation injury than the older children and adults. Followingrecovery from the acuteeffects of radiation, the overall physical status of the children appeared to be normalexcept for the subsequent developmentof thyroid abnormalities, which are discussed below noninfectious diseases, congenital anomalies, and physiological variations has been noted in both ex- posed and unexposed children. 3. Growth Status Interpretation of the anthropometric data and assessment of the growth status of the exposed Rongelap children have been complicated by (a) radiation injury to the thyroid gland, (b) partial or total thyroidectomies in the children who developed thyroid neoplasia, and (c) the administration of thyroid hormoneto the entire exposed Rongelap population since September 1965. If the data on the three children (Nos. 3, 5, and 65) who were obviously hypothyroid and had markedly small body measurements are excluded, compari- sons of mean stature and skeletal age indicated no statistically significant difference between the exposed and unexposed children for either boys or girls. Compared with American norms, the mean skeletal ages at given chronological ages for each group were, for unexposed girls, quite similar, but for unexposed boys, they appeared to be delayed by 6 to 7 months at each chronological age. Earlier preliminary comparisons had suggested that boys exposed at age <(3 years were retarded in statural growth compared with unexposed boys. The current analysis excludes those with a specific diagnosis of hypothyroidism. The individual growth and development curves for 13 children exposed at age <5 and their controls are shownin Figures 21 and 22. The effect of thyroid treatmenton the two boys (Nos. 3 and 5) is evident. Several other children (Nos. 2, 19, 65, 42) had a tendencyto- wardretarded development, which may have been improved by thyroid medication. Onthe 4 children exposed in uéero, careful exam- inations have resulted in no unusual physicalfindings. The growth progress of 3 of them has been similar to that of age peers (see Table 16). One boy (No. 85) has had a head circumference smaller than the average for unexposed males and a slightly retarded pattern of skeletal maturation, but his statural growth curve was comparable with that of unexposed males.