27 88 86 12 - 2 268 5 1.3 27C 11 59 89 48 320 148 25 28 23 29 77 6 153 59 9.7 28C 53 67 47 14 83 24 4.8 in the control group. With the small number of cases involved the probable error is too great to allow either of these measures as indicative of relationship. We may say, then, that there is no definite tendency for those of low I.Q. to improve in six months after operation to a greater degree than those of higher I.Q. Finally, in order to compare the results of the various tests, the measures of the gains of the test group in excess of the control were, for each test, expressed in terms of P. E. The averages and medians of these measures are collected in Table XIII. They show a very slight tendency toward gain in weight, height, and weight-height-age relationship; neither improvement nor loss in grip, tapping fatigueability and I.Q., and a rather curious tendency to loss in the Healy scores. This latter is very probably not a true measure since performance in the Healy Picture Completion test shows a rather high variability, and the cases are so few as to make the influence of single very high or low scores unduly great. TABLE XIII Showing improvement in various tests of operative group over and above such improvement in control group. Expressed in Terms of P. E. Weight Height Height- Grip Tapping Tapping I.Q. Healy Weight fatigue P. E. P. E. P. E. P. E. P. E. P. E. P. E. P. E. Average 2.85 1.00 2.02 -.50 .03 -.50 -.94 -1.92 Median 2.80 1.25 .55 -.83 .32 -.50 0 -2.54 CHAPTER IV MEASUREMENT OF IMPROVEMENT AFTER A SECOND INTERVAL OF SIX MONTHS In view of the fact that one of the experimenters[15] found improvement in school work when her study was extended to cover a second time interval after operation, it was deemed advisable to similarly extend the present investigation in order to determine whether our operated cases showed any improvement after twelve months. To this end, the fifty-six children composing the final groups of the first study, were sought after a second interval of about six months. Conditions made it impossible to give all the retests exactly twelve months from the time of the operation. As a matter of fact, the period ranges from ten to seventeen months. An effort was made to keep the interval between tests equal for the two members of a given pair. [15]: A. H. MacPhail, Adenoids and Tonsils: A study showing how the Removal of Enlarged or Diseased Tonsils Affects a Child's Work in School. Ped. Sem., June, 1920, pp. 188-194.