TABLE B

Table showing how time of improvement of "operated cases" compares with improvement among children at random.

Period 1 Period 2 Period 3 A--Per cent of 31 cases 322 (operated upon) Per cent of 100 children 42 at random

B--Per cent of 18 children--20 333 666 months (operated upon) Per cent of 100 children at 42 41 random

C--Per cent of 11 cases for 30 363 635 100 months (operated upon) Per cent of 100 children at 42 41 41 random

"... Immediately after operation, there seems to be a dropping off in the quality of school work done," but thereafter a marked improvement while the random group shows a comparatively static percentage of improvement from year to year. The conclusion of the author is:

"Here seems good reason to believe that the removal of diseased tonsils and adenoids is a factor in beneficially influencing the mental life of the school child. Not only is the health impaired by failure to remove these diseased parts but the mental life and activity of the child as well."

It is conceivable that pedagogical r.e.t.a.r.dation might exist without any defect of intelligence. The physical effects of adenoids and tonsils might produce a tendency to fatigue, an emotional instability and consequent lack in attention, which would seriously influence the quality of school work, even though the child were of normal or superior intelligence. The relation of physical defects to intelligence has been investigated experimentally by a method which will be employed to some extent in the present investigation. In the two studies to which I refer psychological tests, rather than school standings were used as a basis for judging the intelligence. In each the effects of treatment were measured, and in one, a control group makes possible a more accurate interpretation of results.

The first of these investigations is described by Wallin.[13] It was "an attempt to determine by controlled, objective, mental measures the influence of hygiene and operative dental treatment upon the intellectual efficiency and working capacity of a squad of twenty-seven public school children in Marion School, Cleveland, Ohio (ten boys and seventeen girls), all of whom were handicapped to a considerable degree with diseased dentures or gums, and an insanitary oral cavity." The experiment extended over one year, from May, 1910, to May, 1911. The treatment included corrective work upon the teeth and mouth, and also instruction in oral hygiene, and follow-up work by an employed nurse.

Five series of psychological tests were given at stated intervals during the course of the experiment. They included tests of immediate recall, spontaneous and controlled a.s.sociation (opposites), adding, and attention-perception (cancellation). There were six sets of each test, numbered from one to six, of equal difficulty, and given under uniform conditions. Tests 1 and 2 were given before the treatment began, and the average was taken as the "initial efficiency." The last four, or the last two, were averaged to represent the pupils' "terminal efficiency."

[13]: Wallin: "Mental Health of the School Child." 1914.

The results show the following influence of dental treatment upon the working efficiency of the pupils.

1. The indices of improvement are about the same for boys and girls.

2. Improvement was about the same for older and younger pupils.

3. There were great individual differences in initial proficiency and in improvement.

4. Improvement in one test does not presuppose improvement in another.

5. There is a decided gain in every test, "and not only are the gains decidedly more frequent than the losses but the largest gains are invariably emphatically larger than the largest losses."

6. The average gains in the tests were:

Memory, 19 per cent with 8 losses and 19 gains.

Spontaneous a.s.sociation, 42 per cent with 2 losses and 25 gains, Addition, 35 per cent with 1 loss and 26 gains.

Controlled a.s.sociation, 29 per cent with 0 losses.

Perception-attention, 69 per cent with 0 losses.

Average gain for all tests, 57 per cent.

Unfortunately, Wallin was unable to form a control group, so that it is impossible to estimate accurately how much of this gain is due to the treatment of the defect, and how much to other causes, such as growth, etc. "But," the writer adds, "if we concede that one-half of the gain--and that is, I believe, a sufficiently liberal concession--is due to a number of extrinsic factors, such as familiarity, practice and increased maturity, the gain solely attributable to the heightened mentation resulting from the physical improvement of the pupils would still be very considerable. There is corroborative evidence to show that there was a general improvement in the mental functioning of these pupils. This evidence is supplied by the examination of the pedagogical record of scholarship, attendance and deportment. Most of the members of this experiment squad were laggards, and repeaters, pedagogically r.e.t.a.r.ded in their school work from one to four years, but during the experiment year only one pupil failed of promotion, while six did thirty-eight weeks of work in twenty-four weeks, and one boy finished two years of work within the experimental year."

The second investigation was equally careful in its method. It was pursued by the Rockefeller Foundation, under the direction of E. K.

Strong, with the purpose of examining the "Effects of Hookworm Disease on the Mental and Physical Development of Children."

The children were divided into five groups and tested at intervals of three and one-half months. The tests used were opposites, calculation, logical memory, memory span, hand-writing, form-board, and Binet-Simon.

After the first test-series was given, the five groups were divided into sub-groups on the basis of this initial performance, so that the improvement was compared only for those sub-groups in which this was equal.

The improvement of Group A--uninfected children--proved to be greatest, and was taken as 100 per cent. On this basis, Group B--infected children not treated--showed the least improvement,--only 34 per cent. Group C--children completely cured of infection--improved 60 per cent. Group D--severely infected children, treated but not completely cured--improved 38 per cent, and Group Du--an older sub-group of D--improved 9 per cent as much as the normal children, and much less than the untreated younger children. Dr. Strong reaches the following conclusion:

"The figures show, then, that hookworm disease unmistakably affects mental development. Treatment alleviates this condition to some extent but it does not, immediately, at least, permit the child to gain as he would if he had not had the disease. And the figures apparently further show that prolonged infection may produce prolonged effects upon mentality,--effects from which the individual may never recover."

CHAPTER II.

METHOD AND PROCEDURE

The following investigation was carried on during the year and a half from October, 1919, to April, 1921. The subjects were pupils at Public School 64, Manhattan, or patients at the Manhattan Eye, Ear and Throat Hospital. All were boys, between the ages of six and fourteen years. The testing in the study of improvement was done by the investigator, a.s.sisted by three other examiners, all competent and experienced in the technique of giving psychological tests.

A Statistical Study

In addition to the more lengthy experiment, a statistical study was made, comparing the intelligence levels of two groups of children, the one selected for the presence of tonsils, the other for freedom from them. These two groups were obtained from a large group of 530 children whose I.Q.'s were gained from the records of Public School 64, where, so far as possible, all children are tested upon entering school. We had, therefore, a group unselected for intelligence level.

All the children for whom we had I.Q.'s were examined by the school nurse or physician. On the basis of this examination the two groups were selected. The tonsil group consisted of those cases which in the opinion of the nurse or doctor, were p.r.o.nounced enough to deserve treatment. The normal group was composed of those who were not defective, or in whom the defect was so slight as not to demand treatment. The two groups were arranged each in a surface of distribution according to the I.Q.'s of the members. The results of the distribution appear in Table I, and in Figs. I. and II.

A Study of Improvement After Treatment

The method employed here is based on the hypothesis that if a physical defect is the cause of r.e.t.a.r.dation in mental or physical development, removal of the cause will tend to lessen the r.e.t.a.r.dation. In other words, if a child's working efficiency is lowered by the effects of adenoids and bad tonsils, their removal should, unless such lowering be permanent, be followed after a reasonable time by an improvement. But improvement in efficiency, following the removal of adenoids and tonsils proves nothing unless we shall compare it with the change in efficiency of a control group, whose members have not been operated on, and who thus still suffer from the effects of the growths.

Selection of Cases

The selection of the children for the experiment was effected in the following manner. The teachers at Public School 64 were asked to report any cases which had come to their notice, as being seriously afflicted with adenoids and diseased tonsils. In this way a fairly large group was obtained. The parents of the children were visited with the purpose of obtaining permission for examination and operation at the Post Graduate Hospital. It was fairly easy to obtain permission to have the children examined. They were taken in groups of four or five to the clinic, the experimenter attending in person every examination in order to learn from the doctors the degree of the defect. As a result of this method, we discarded all those cases where there was any doubt as to the serious nature of the defect.

From the large group examined, we were finally successful in securing operative treatment for 10 children. Discarding the cases where defect was slight, there remained a number of children who, for one reason or another, did not undergo operation. In some instances the parents refused their permission, in some they failed to keep appointments, in one or two there was sickness in the family, and in a number the hospital was overcrowded and could not receive the children. All members of this group were examined,--to the number of fifty-six, and from them the control group was finally selected.

Since we were unable to secure a large test group from Public School 64, the experiment was continued at the Manhattan Eye, Ear and Throat Hospital where opportunity was given for testing the children after they had been admitted for operation. In order to be sure that in each case the defect was sufficiently p.r.o.nounced to render decisive the results of the experiment, each child's card was examined. Only those children were included who were undergoing operation for both adenoids and tonsils.

It may be here remarked that mental tests were given to these children on the morning of operation, and in some cases only a short time before it. The possibility suggests itself, therefore, that the results of the tests may have been influenced by excitement or fright on the part of the patients. Actually, however, this did not seem to be the case. The children were perfectly cheerful and showed no signs of nervousness. The tests were given in a waiting room with the door closed so that any disturbing sights and sounds were eliminated. The possible lowering of the performance by the causes mentioned would tend to exaggerate the improvement shown by the retests, so that in the light of the results, it will be seen that they could have had little effect.

The test group, then, was composed of forty members; ten from Public school 64, who received operation at the Post Graduate Hospital, and the remaining thirty from various schools throughout the city, patients at the Manhattan Eye, Ear and Throat Hospital. The control group of forty was selected as previously described, and the pairs were arranged so as to have the ages of the members of one pair as nearly as possible the same.

The Tests

Since the main interest of this investigation lies with intellectual development, two tests of intelligence were given: namely, Terman's revision of the Binet test, and Healy's Picture Completion Test, number II. The starred Terman was always used, since it was necessary to economize time.

It was expected that improvement in general health would probably follow the removal of the defects. This physical gain should come to light in increased height and weight. In every case, therefore, height and weight were measured.

It is conceivable that adenoids and tonsils might have no effect upon general intelligence, and yet might cause a noticeable pedagogical r.e.t.a.r.dation, simply as a result of the child's physical handicap, tendency to fatigue and consequent defect in attention or sustained effort. In order to gain some measure of this physical factor, strength of grip and speed in tapping were found. An effort was made, also, to obtain teachers' estimates of the pedagogical rankings, but this was for the most part unsuccessful, since in many cases teachers misunderstood directions, and in others the tests were made too soon after the opening of school for any such estimates to be possible.

The tests described above were given before the operation to each child in the test group, allowing as short an interval as possible between test and operation. In the case of the Manhattan Hospital children, test and operation fell on the same day. In no case did the interval exceed ten days. The members of the control group were tested, each one within a week of his partner.[14]