1 in Section IV. The other physical findings, which Table 15 have been carefully tabulated in the individual reports tor each survey, indicate no definite pattern Composition of Pediatric Groups, 1972 Age at exposure, yr Rongelap group - <10 10-19 In utero Ailingnae group No. males No. females 10 5 9 9 2 + 22 11 19 7 3 <10 Unexposed group Born 1945-1954 Born 1935-1944 1 skeletal development (left hand and wrist) was initiated,+! and systematic documentation of anthropometric 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 data recorded regularly included standing height (stature), body weight, head circumference, head width, head length, chest circumference, biacromial width, and calf circumference, and spo- radically includedsitting height, chest width, chest depth, and buttocks circumference. (See Appendix 7.) . The development of secondary sex characteristics was qualitatively assessed according to the standard criteria generally accepted in growth studies (Greulich et al.,*? Shuttleworth*$). Such procedures included the staging of breast development in girls: estimation of the type, pattern, and amount of body hair (facial, pubic, axillary, etc.}. and staging of the growth of penis andtestes in boys. During several examinations, photographic 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,41 and the American standards were used for comparison. 2. Physical Findings The early post-exposure examinations indicated that the vounger children, in general, manifested more extensive and moresevere radiation injury than the older children and adults. Following re- covervfrom the acute effects of radiation, the over- all physical status of the children appearedto be normal except for the subsequent developmentof thyroid abnormalities, which are discussed below of abnormalities that would differentiate the exposed children from the unexposed comparison children. The usual spectrum of infectious and noninfectious diseases, congenital anomalies, and phvsiological variations has been noted in both exposed and unexposedchildren. 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 thvroidectomies in the children who de- veloped 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 63) who were obviously hypothvroid and had markedly small body measurements are excluded, comparisons of meanstature andskeletal 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 unexposedgirls, quite similar, but for unexposed boys, they appeared to be delaved by 6 to 7 monthsat each chronological age. Earlier preliminary comparisons had suggested that boys exposed at age <(5 years were retarded in staturalgrowth compared with unexposed boys. The current analysis excludes those with a specific diagnosis of hypothyroidism. The individual growth and developmentcurves for 13 children exposed at age <5 andtheir controls are shown in Figures 21 and 22. The effect of thyroid treatment on the two boys (Nos. 3 and 5) is evident. Several other children (Nos. 2, 19, 65, 42) had a tendency to- ward retarded development, which may have been improved by thyroid medication. Onthe 4 children exposed in utero, careful examinations have resulted in no unusualphysicalfindings. 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.