12
[mpairment oPRéaring was averaged for the two
ears as follows.ihedecibel loss for each of seven
frequencies (200, 500, 1000, 2000, 3000, 4000. and
7000) tn each ear was averaged to give a mean
frequencyloss in decibels for the two ears.
Cardiovascular Changes.
|. Systolic and diastolig dlood pressures were obtained with the stand-
ard aeronoid cuff-tvpe sphygmomanometer. Iwo
readings were obtained, and the average value
was used. There was no basic cr adjusted level of
physical activity such as resting for a standard
period prior to the readings. Pressures were taken
on the left arm with the subject supine during the
course of the physical examination.
2. The degrees of peripheral arteriosclerosis and
retinal arteriosclerosis were scored on aQ) to + scale.
The former was estimated by palpation of the
peripheral arteries, the latrer by viewing the retina
with an ophthalmoscope.
Neuromuscular Function.
Neuromuscular func-
tion was measured by having the subject depress
the key of a hand tally type of blood cell counter
as many times as possible in the period of one minute. The total number of depressions represented
the score,
Hand Strength.
Hand strength was measured
by a Smedley hand dynamometer.* The spring
tension of the hand grip was measured in kilo-
grams. The maximum squeeze strength in the
dominant hand in three tries was recorded.
Handling of Data.
Because of sex differences,
some of the above criteria were evaluated separately for the two sexes; these were baldness, neuro-
muscular function, and hand strength.
In order that the estimated and measured data
could be compared and combined, both types of
data were converted to a percentagescale. The
estimated values 0,1+,2+,3+,and4+ were presented also as 0, 25, 50, 75, and 100%, respectively.
In the case of the measured data,the values associated with least aging were taken as zero percent
(sometimes the highest reading, as with hand
strength; sometimes the lowest, as with hearing
loss), and those indicating most aging as 100%.
The data were examined on both an individual
basis and a population basis. A mean age scoke
was obtained for each individual by averagingall
his percent test values. In studying population
trends, means were calculated for each criterion
by 3-year age groups (1n most cases) including
*C.H. Stoeiting Company, Chicago, III.
1185502
combined exposed and unexposed populations:
these were plotted, and a curve was drawn according to the best fit bv eye. A curve was obtained in
the same way. of the 5-vear group means of the
individual mean age scores. The combining of
scores into 3-vear age groups was done to reduce
possible errors due to the uncertainty of the exact
age of some individuals.
Laboratory Procedures
Hematological Examinations.
Two complete
routine blood counts were done, about a week
apart, and a third was done on persons showing
abnormalities. White blood counts, red blood
counts, and Price-Jones curves (for determination
of red cell size distribution) were obtained with
the electronic Coulter, which proved verysatisfactory and time-saving for this type of field examina-
tion. Differential counts were performed in the
usual manner after staining with Wright's fluid.
Platelet counts were done by phase microscopy,
and hemoglobin was determined by the cyan-
hemoglobin technique with the Lumitron col6rim-
eter. Serum proteins were determined with the
Hitachi refractometer. Blood and serum samples
for the studies described below were collected in
the field, kept under refrigeration, and shipped by
air to the various laboratories in the United States
for analysis.
Urine Analyses.
Routine urine analyses were
carried out on all people receiving physical exam-
inations. These included determinationsof protein and hyperglucosuria by reagent paperstrips. *
In all cases showing positive findings, the urine
was centrifuged and the sediment examined microscopically. In the four cases showing positive
urine sugartests, fasting blood specimens were obtained and analyzed for blood sugar at the Naval
Dispensary on Kwajalein.
Serum Cholesterol.
Serum cholesterol was
determined in blood samples drawn from exposed
and unexposed Rongelap people, and also in
about 70 blood samples from people at Uurik
Island and 63 from people at Majuro Atoll. These
analyses were done at the National Institutes of
Health by Dr. J.H. Bragdon and Mr. J.C. Lauter.
Complement Fixation Tests. Serum samples obtained from 163 exposed and unexposed Rongelap
people were frozen and sent to the National [nsti-
tutes of Health for various examinations. Com*Clinistix, Ames Company, Inc., Elkhart, Indiana,
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