12
Impairmentof hearing was averagedfor the two
ears as follows: the decibel loss for each of seven
frequencies (200, 500, 1000, 2000, 3000, 4000, and
7000) in each ear was averaged to give a mean
frequency loss in decibels for the twoears.
Cardiovascular Changes.
1. Systolic and dias-
tolic blood pressures were obtained with the stand-
ard aeronoid cuff-type sphygmomanometer. Two
readings were obtained, and the average value
was used. There was no basic or 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 artertosclerosts were scored on a 0 to 4+ scale.
The former was estimated by palpation of the
peripheralarteries, the latter by viewing the retina
with an ophthalmoscope.
Neuromuscular Function. Neuromuscular function was measured by having the subject depress
the key of a hand tally type of blood cell counter
as many timesas possible in the period of one min-
ute. The total number of depressions represented
the score.
Hand Strength. Handstrength was measured
by a Smedley hand dynamometer.* Thespring
tension of the hand grip was measuredin kilograms. The maximum squeezestrength in the
dominanthand in three tries was recorded.
Handling of Data.
Because of sex differences,
some of the above criteria were evaluated sepa-
rately 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 percentage scale. The
estimated values 0,1+,2+,3+,and 4+ were presented also as 0, 25, 50, 75, and 100%, respectively.
In the case of the measured data, the values associ-
ated 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 anindividual
basis and a population basis. A mean agescore
was obtained for each individual by averagingall
his percent test values. In studying population
trends, means were calculated for each criterion
by 5-year age groups (in most cases) including
*C.H. Stoelting Company, Chicago,I).
S60 TST
combined exposed and unexposed populations;
these were plotted, and a curve was drawnaccording to the best fit by eye. A curve was obtained in
the same way of the 5-year group meansofthe
individual mean age scores. The combining of
scores into 5-year age groups was done to reduce
possible errors due to the uncertainty of the exact
age of some individuals.
Laboratory Procedures
Hematological Examinations.
“Iwo 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 very satisfactory and time-saving for this type of field examina-_
tion. Differential counts were performed in the
usual mannerafter staining with Wright’s fluid.
Platelet counts were done by phase microscopy,
and hemoglobin was determined by the cyanhemoglobin technique with the Lumitron colorimeter. Serum proteins were determined with the
Hitachi refractometer. Blood and serum samples
for the studies described below were collected in
the field, kept underrefrigeration, 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 examinations. These included determinations of protein and hyperglucosuria by reagent paperstrips.*
In all cases showing positive findings, the urine
wascentrifuged 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 Utirik
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.
ComplementFixation Tests. Serum samples obtained from 163 exposed and unexposed Rongelap
people were frozen and sent to the Nationa! Insti-
tutes of Health for various examinations. Com*Clinistix, Ames Company, Inc., Elkhart, Indiana.