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 retardation, 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] [14]: In a few cases where the operation was postponed after the test had been given, the child and his control were retested just previous to the operation. Since both cases were retested, practice effect is of no great importance. Six months after his first test, each child was retested, whenever possible. Since some children had dropped out of the groups for one reason or another, the final number in each group was twenty-eight. It was necessary to rearrange the control cases somewhat in order to fill in spaces left vacant by those who were lost. In this rearrangement, the effort was made, 1. to pair cases whose ages were approximately the same; 2. to pair cases whose first tests were dated fairly close together. Since all the children were tested and retested under approximately the same conditions, this rearrangement will probably not greatly influence the results. The tests were always given in the same order.