Adenoids and Diseased Tonsils: Their Effect on General Intelligence

by Margaret Cobb Rogers

TABLE II. RESULTS (Continued)

Blank spaces indicate where tests were omitted for one reason or another

N	Tapping, 1/2 min. best hand		I.Q.		Healy, Score
	1	2	1	2	1	2
1	135	120	82	83	-25	-2
1C	106	115	80	76	-50	-16
2	105	112	107	114	28·5	30
2C	152	114	91	96	3	-11
3	136	139	94	91	21·5	22·5
3C	135	129	82	85	17	19
4	103		96	96	8·5
4C	109		83	85	33
5	110		95	99	-25
5C	156		114	117	40·5
6	110		95	101	-33
6C	126		88	89	-32
7	125	113	91	99	6	-28
7C	105		95	99	4·5	27·5
8	113	110	91	86	32·5
8C	131	101	98	104	4	23
9	149	135	83	93	3·5	10·5
9C	144	150	87	90	34	55
10	68+ 74	88+ 82	110	109	-12	6·5
10C	70+ 54	135+109	104	100	27	65
11	125+ 90	98+ 87	103	100	- 8	6
11C	155+125	101+107	101	102	-29	-3·5
12	98+69		98	95	20	21
12C	102	84	98	101	-10	-12
13	160+165	142+134	70	78	43	42
13C	150+109	122+ 94	66	64	- 1·5	30·5
14	190+172	138+130	96	107	12·5	48·5
14C	175+152	175+164	140	137	- 5	25·5
15	172+167	170+156	97	94	7	25
15C	140+115	137+115	78	79	1	42·5
16	145+131		65	73	49	47·5
16C	145+99	135+135	74	82	30	37
17	90+89	150+100	71	77	29·5	12
17C	125+116	121+ 97	96	99	1·5	15
18	133+115	135+111	98	98	-13·5	-12
18C	100+ 99	84+ 74	90	94	-32	-28
19	168+136		96	101	57·5	49
19C	100+115	118+ 92	98	98	-22	-11
20	105+115	110+ 93	106	102	0	-11
20C	150+120	155+149	118	131	30	35
21	152+111	132+125	64	67	20	32
21C	140+136	138+110	86	97	70·5	58·5
22	164+148	183+141	91	100	48·5	43·5
22C	120+116	157+127	63	62	34·5	33·5
23	150+119	141+136	85	94	49·5	68
23C	122+115	140+110	81	96	4	25
24	157+136	142+126	131	124	54·5	63
24C	155+135	155+100	89	92	31·5	59·5
25	140+127	150+119	77	76	8	25
25C	148+134	151+135	145	137	29·5	29
26	137+113	138+117	80	76	22·5	7
26C	125+105	125+ 79	90	88	56	61·5
27	108+ 92	97+ 92	110	109	-25	15
27C	115+105	112+109	72	96	2	27·5
28	150+148	162+143	81	84	29·5	73·5
28C	178+148	170+163	95	98	64·5	51·5

We have therefore:

28 pairs of I.Q's to be compared
21 pairs of weights
19 pairs of heights
16 pairs of grip measurements
20 pairs of tapping speeds
24 pairs of Healy Completion scores.

Again, in only five pairs does the gain of the control exceed that of the test case, while in the remaining sixteen pairs the gains of the test cases are greater than those of their respective controls. The greatest loss of test as compared to control is 4·2 lbs., while the largest gain is 7·9. It would seem then, that after a six months' interval a child who has been operated on for adenoids and tonsils will tend to show a slightly greater increase in weight than a child who continues to suffer from the defects. The very small group renders this conclusion far from assured. Since it doubtless takes some little time to recover from the effects of the operation, and since there is comparatively little gain in weight in a six months' interval, it would be well to extend the experiment over another year. For the greater reliability of results, some degree of after-care should be given the operative cases, the control cases of course receiving the same treatment. While this was impracticable in the present study, it happened that three pairs of cases were members of a nutrition class, and therefore underwent some hygienic treatment. In one pair, (no. 11) the test case lost ·3 of a pound, while the control gained ·9. The test cases of pairs 7 and 10 gained ·8 lb. and 2·1 lbs. respectively, over and above their controls. However, these three cases alone are of little significance.

A study of increase in height suffers even more than one of weight gains from the short interval which elapsed between measurements. Normally, there is very little growth in six months. There are only nineteen pairs of cases in this portion of the study, a fact which renders it of even less value. However, results are offered for what they are worth. The smallest increase in height (·3 in.) is in the test group, while the greatest growth (3·5 in.) is also in the test group. There is, however, a gain of 3·3 inches in the control group as well as one of only ·4 inches. There are seven pairs in which the test group growth is less than that of the controls, one in which the two are equal, and in the remaining eleven the growth of the test cases exceeds that of the controls. The variability

TABLE III

Gain in weight, 6 months, 21 pairs

N[16]	Test Group (A)			Control Group (B)			Lbs.
	Test 1	Test 2	Gain	Test 1	Test 2	Gain	A-B
8	60·8	63·3	2·5	45·4	52·1	6·7	-4·2
2	40·9	42·9	2·0	52·3	57·4	5·1	-3·1
28	71·3	75·5	4·2	74·2	79·8	5·6	-1·4
6	43·8	44·5	·7	50·6	52·5	1·9	-1·2
11	47·8	47·5	-·3	41·6	42·5	·9	-1·2
1	50·4	54·2	3·8	53·5	57·2	3·7	·1
7	39·9	41·0	1·1	38·4	38·7	·3	·8
9	50·6	53·2	2·6	59·8	61·4	1·6	1·0
12	48·0	52·5	4·5	41·0	44·5	3·5	1·0
14	56·0	62·0	6·0	81·9	86·0	4·9	1·1
5	45·0	47·0	2·0	56·2	57·0	·8	1·2
21	70·7	76·5	5·8	62·4	67·0	4·6	1·2
4	51·1	54·2	3·1	49·4	51·0	1·6	1·5
10	48·9	51·4	2·5	47·1	47·5	·4	2·1
16	56·0	57·0	1·0	51·2	50·0	-1·2	2·2
24	58·5	62·5	4·0	60·0	61·0	1·0	3·0
3	55·0	59·5	4·5	61·5	62·9	1·4	3·1
25	55·5	59·5	4·0	63·3	63·8	·5	3·5
19	90·0	96·3	6·3	52·4	54·4	2·0	4·3
13	90·0	98·0	8·0	74·7	76·8	2·1	5·9
26	63·8	74·5	10·7	64·2	67·0	2·8	7·9
Av·	56·86	60·61	3·76	56·24	58·60	2·39	1·37
M			3·80			1·9	1·2
75%ile			5·80			4·6	3·1
25%ile			2·00			·9	0·1
Q			1·90			1·85	1·5
P. E. (distribution)			1·76			1·39	1·63
P. E. (average)			±·38			±·30	±·48
						Av. =2·85 P. E.
						M. =2·80 P. E.

of the test group growth is greater than that of the control group. The three nutrition pairs show the following records of growth,—in number 7, the test case shows a growth of ·6 in. more than his control. Number 10 is the pair in which the growth is equal. In number 11 the test case again exceeds in growth by ·6 of an inch.

More reliable than height and weight considered separately, as an index of physical welfare, is weight in relation to height and age. Table V shows the improvement in this relationship for the two groups. The numbers in columns 1, 2, 4 and 5 show the per cent under or over weight of the individual cases, in relation to their respective heights and ages. The authority upon which the figures are based, is the table published by the American Child Health Association, giving standard weights for height and age in boys.

There was an average loss of ·28 per cent in the weight-height-age relationship for the test group, and of 2·11 per cent for the control group. The average improvement of the test group in excess of the control group is, then, 1·83 per cent. The median improvement of test group over and above control is 4·00 per cent. The test group is more variable than the control in improvement. The greatest improvement, 8 per cent, is found in both groups.

TABLE IV

Gain in Height—6 Months, 19 Pairs

N[16]	Test Group (A)			Control Group (B)			Inches
Test 1	Test 2	Gain	Test 1	Test 2	Gain	A-B
9	48·1	49·4	1·3	51·9	55·2	3·3	-2·0
4	47·5	49·2	1·7	48·9	52·0	3·1	-1·4
5	44·9	45·2	·3	46·6	48·1	1·5	-1·2
6	43·1	43·9	·8	45·4	47·3	1·9	-1·1
2	42·5	44·1	1·6	45·2	47·0	1·8	-·2
28	54·9	55·8	·9	53·4	54·5	1·1	-·2
16	51·6	52·3	·7	48·7	49·5	·8	-·1
10	46·1	47·7	1·6	45·6	47·2	1·6	0
25	50·0	50·8	·8	50·2	50·9	·7	·1
1	46·0	47·6	1·6	46·4	47·8	1·4	·2
3	47·0	48·4	1·4	51·7	52·9	1·2	·2
8	50·8	51·8	1·0	46·8	47·6	·8	·2
14	51·0	51·6	·6	57·9	58·3	·4	·2
7	42·9	44·8	1·9	41·9	43·2	1·3	·6
11	45·8	47·7	1·9	43·6	44·9	1·3	·6
19	57·7	59·0	1·3	46·7	47·2	·5	·8
26	51·6	54·3	2·7	51·4	52·3	·9	1·8
22	53·0	56·4	3·4	56·8	58·1	1·3	2·1
13	61·5	65·0	3·5	56·8	57·8	1·0	2·5
Av.	49·26	50·79	1·53		50·62	1·36	·16
M			1·4			1·3	·2
75%ile			1·9			1·75	·65
25%ile			·78			·8	-·43
Q			·56			·48	·54
P. E. (distribution)			·53			·44	·44
P. E. (average)			±·12			±·10	±·16
						Av.=1 P. E.
						M=1·25 P. E.

The greatest loss, 10 per cent, is in the control group. Eight cases show a loss in comparison to their controls, and nine reveal a gain. On the whole, there is some significance in the small net improvement manifested by the test group. The average is 2·02 P. E.'s, and the median 4·40 P. E.'s.

The dynamometer results show no gain in strength of grip six months after operation. Indeed the average of the gains of the operative cases is slightly less than the average gain of the controls. Comparing the test group with the control, we find the average of the differences to be -·24. But the variability is so high (P. E. = ±·48) as to render this figure unreliable. The greatest loss in strength of grip is found in the control group, but the greatest gain is also in this group. Seven cases in the test group show a loss, as compared with only three control cases. In eight, or one-half of the sixteen cases, the control member of a pair gained more than the test member. Considering the three pairs of nutrition cases, we find that in pair number 7 the test case loses 1·5 Kg. when compared with the control; and in pair number 10, 6·5 Kg., while the test case in pair 11 gains 4 Kg. The conclusion from the data would seem to be that, within the space of six months at any rate, operation for adenoids and tonsils brings about no increase in strength of grip.

TABLE V

Showing change in per cent over or underweight for height and age, 18 pairs.

			A			B	A-B
N[16]	1	2	3	4	5	6	7
8	- 1	- 1	0	-13	- 5	+ 8	- 8
11	- 3	-12	-9	- 9	-11	- 2	- 7
10	- 1	- 5	-4	- 6	- 8	- 2	- 2
28	- 7	- 7	0	0	+ 2	+ 2	- 2
13	-13	-19	-6	-11	-15	- 4	- 2
19	+ 6	+ 8	+2	+ 1	+ 5	+ 4	- 2
6	+ 2	- 3	-5	+ 5	+ 1	- 4	- 1
14	-13	- 9	+4	- 5	0	+ 5	- 1
7	- 8	-15	-7	- 7	-14	- 7	0
2	- 8	- 6	+2	+ 9	+10	+ 1	+ 1
3	+ 6	+ 8	+2	- 5	- 8	- 3	+ 5
16	-16	-15	+1	-13	-17	- 4	+ 5
25	- 8	- 7	+1	+ 4	- 1	- 5	+ 6
5	- 4	- 1	+3	+ 8	+ 4	- 4	+ 7
9	- 8	-11	-3	- 7	-17	-10	+ 7
26	- 1	+ 5	+6	+ 1	0	- 1	+ 7
4	- 7	- 7	0	-15	-23	- 8	+ 8
1	0	+ 8	+8	+ 8	+ 4	- 4	+12
Av.	- 4·67	- 4·94	- ·28	- 3·06	- 5·17	- 2·11	+ 1·83
M			+ ·5			- 3·50	+ 4·00
75%ile			+2			0.00	+ 6·50
25%ile			-2			- 4·50	- 2.00
Q			2			2·25	+ 4·25
P. E. (distribution)			3			2.39	+ 1·33
P. E. (average)			± ·71			± ·57	± ·91
						Av.=2·02 P. E.
						M.=4·40 P. E.

Is there, after operation, an improvement in motor control and attention, and a lessening of fatiguability as these may be demonstrated in the tapping test? Table VI gives the number of taps in the first half minute of tapping for both groups before and after the six months interval. The test group suffers an average loss of 2·24 taps, and a median loss of 2· The average loss of the control group is 2·33, and the median 2·

TABLE VI

Gain in Grip—6 Months— 16 Pairs

N[16]	Test Group (A)			Control Group (B)
	Test 1	Test 2	Gain	Test 1	Test 2	Gain
10	12·5	11	-1·5	10	15	5	-6·5
27	9	6	-3	8	9	1	-4
1	13	12	-1	11	13	2	-3
14	16	15	-1	22	24	2	-3
2	9	9	0	10	12	2	-2
9	10·5	13	2·5	16·5	21	4·5	-2
7	7	6·5	- ·5	9	10	1	-1·5
16	19	17·5	-1·5	10	10	0	-1·5
3	12·8	14·5	1·7	14	15	1	·7
13	26·5	28·5	2	22	23	1	1
24	19	20	1	15	15	0	1
19	22	21	-1	15	12	-3	2
22	18	22·5	4·5	19·5	21·5	2	2·5
11	11	15	4	11·5	11·5	0	4
21	16·5	16·5	0	19	15	-4	4
23	11·5	15·5	4	14·5	14	- ·5	4·5
Av.	14·58	15·22	·62	14·19	15·06	·875	- ·24
M			0			1	-1·0
75%ile			3			2	-2·25
25%ile			-1			0	-2·50
Q			2			1	-2·38
P. E. (distribution)			1·58			1·02	-2·49
P. E. (average)			±·40			±·26	± ·48
						Av.= -·50 P. E.
						M.= -2·08 P. E.

There is practically no change then in the tapping ability of either group. The high unreliability of the difference (P. E. = ± 3·10) is noteworthy. It would seem that incidental causes have a much greater effect upon tapping ability than can be demonstrated as resulting from the removal of adenoids and tonsils.

Use of the tapping test as a measure of the decrease in tendency to fatigue similarly brings out no indication of any improvement in the operative group of cases. The measure of fatigue was taken as a ratio; namely, the number of taps in the first, minus the number in the second half minute over the number of taps in the first half minute. Then, if there is a greater number of taps in the second, the ratio will be minus, indicating that fatigue effect is so small as to be overcome by practice effect. This was a fact in only four cases. Since what we are measuring is improvement, the ratio for test 2 is subtracted from the ratio for test 1 to find the gain in overcoming fatigue. Table VIII shows the average gain for group one to be -·0196, and the median -·045. That is, there is an average increase in fatiguability of ·0196 units and a median increase of ·045 with a P. E. of ± ·02. This increase in fatiguability occurs also in the control group, average 0, and median ·03 with P. E. of ± ·03. The average gain of test group over control group is -·02 and the median gain is -·015. Again variability is relatively large, P. E. being 1·04, so that the median and average gains are -·50 P. E. and -·38 P. E. respectively.

We may say, then, that the capacities brought out by the tapping test seem to undergo no improvement in six months after removal of adenoids and tonsils.

The main line of interest in the present experiment lay with the relation of adenoid and tonsil defects to general intelligence. The results of the two tests dealing more specifically with this side of the problem are here set forth. Table IX shows the I.Q's. of the two groups before and after the six months' interval, together with changes plus or minus in I.Q., and a comparison of the separate pairs in respect to improvement.

We find that the test group shows an average gain in I.Q. of 2·25 points. The median gain is 2 points, the total range 18 points and P. E. of the average is ± ·99. The control group shows an average gain very slightly higher, 3·25 points, the median gain being 3. The range in this case is 32 points, but P. E. is only ± ·47. The average of the compared gains of separate pairs is -1·035. These numbers are so small as to be insignificant. Actually, we may say that the operative group as a whole showed no gain over the control group. If we examine individual cases we find that the greatest loss in I.Q. was in the control group, (8 points) but the greatest gain (24 points) also appears in this group. In the test group 11 cases

TABLE VII

Gain in number of taps in one-half minute, 21 pairs—right hand

N[16]	Test Group (A)			Control Group (B)
Test 1	Test 2	Gain	Test 1	Test 2	Gain
14	190	138	-52	175	175	0	-52
10	68	88	20	70	135	65	-45
23	150	141	- 9	122	140	18	-27
1	135	120	-15	106	115	9	-24
9	149	135	-14	144	150	6	-20
21	152	132	-20	140	138	- 2	-18
22	164	183	19	120	157	37	-18
24	157	142	-15	155	155	0	-15
27	108	97	-11	115	112	- 3	- 8
20	105	110	5	150	155	5	0
15	172	170	- 2	140	137	- 3	1
26	137	138	1	125	125	0	1
25	140	150	10	148	151	3	7
3	136	139	3	135	129	- 6	9
13	160	142	-18	150	122	-28	10
18	133	135	2	100	84	-16	18
28	150	162	12	178	170	- 8	20
8	113	110	- 3	131	101	-30	27
11	125	98	-27	155	101	-54	27
2	105	112	7	152	114	-38	45
17	90	150	60	125	121	- 4	64
Av.	135·19	132·95	- 2·24	136·47	134·14	- 2·33	·09
M			-2			-2	0
75%ile			6·5			4·5	16·0
25%ile			-15			-14	19·50
Q			10·75			9·25	17·75
P. E. (distribution)			12·24			7·33	18·09
P. E. (average)			2·66			±1·59	±3·10
						Av.= ·03 P. E.
						M.= 0 P. E.

lost in I.Q., as compared with 7 in the control group. Thirteen test cases lost in comparison with their respective controls. Two gained equally with their controls, and the remaining thirteen showed a larger gain. In regard to the three pairs taken from the nutrition class, number 7 gained 8 points and his control, 4. Number 10 lost a point and his control lost 4, while number 11 lost 3 points with a gain of 1 point by his control. So that these cases, in spite of most favorable conditions, show no consistent gain in I.Q.

The results of the Healy tests are similar. There is a slightly higher average gain in the control group. The test group contains eight cases which made a poorer score at the end of the interval, the control group six. The range of gains is from -22 to +44, or 66 points, in the test group, while in the control group the gains range from -14 to +41·5 or 55·5

TABLE VIII

Decrease in fatigue in tapping—Difference in rates of second half minute over first half minute. Sixteen pairs

N[16]]	Test Group (A)			Control Group (B)
Test 1	Test 2	Gain	Test 1	Test 2	Gain
13	-·03	·05	-·08	·27	-·28	·55	-·63
28	·01	·11	-·10	·17	·04	·13	-·23
20	·10	·15	-·05	·20	·04	·16	-·21
10	-·09	·07	-·16	·23	·19	·04	-·20
17	·01	·33	-·32	·07	·20	-·13	-·19
25	·09	·21	-·12	·09	·11	-·02	-·10
11	·28	·11	·17	·19	-·06	·25	-·08
15	·03	·08	-·05	·18	·16	·02	-·07
22	·10	·23	-·13	·03	·19	-·16	·03
27	·15	·05	·10	·09	·03	·06	·04
14	·09	·06	·03	·02	·06	-·04	·07
18	·14	·18	-·04	·01	·12	-·11	·07
24	·13	·11	·02	·13	·35	-·22	·24
26	·18	·15	·03	·16	·37	-·21	·24
23	·21	·04	·17	·06	·21	-·15	·32
21	·27	·05	·22	·03	·20	-·17	·39
Av.	·104	·124	-·020	·121	·121	·0	-·020
M			·045			-·03	-0·015
75%ile			+·03			+·04	·07
25%ile			-·12			-·16	-·20
Q			·075			·10	·135
P. E. (distribution)			·09			·11	·05
P. E. (average)			±·02			±·03	±·04
						Av.= -·50 P. E.
						M.= -·38 P. E.

points. Seventeen of the operative cases showed a smaller gain than their respective controls. The three pairs of cases from the nutrition class show the following gains:—pair 7; the test case loses 22 points, the control gains 23 points; pair 10, test case gains 18·5, but control gains 38 points; pair 11, test case gains 14 points, and control gains 25·5 points. From this test then, we can find no general tendency for cases operated on to improve in intelligence in excess of improvement in a control group which was not so treated.

This question presents itself:—is there any relationship between improvement in physical well-being as revealed in weight, and improvement in intelligence? If, as has been supposed, adenoids and diseased tonsils cause mental retardation indirectly through physical deprivation, it would seem as though greater improvement in intelligence after operation should accompany greater improvement in weight, and smaller intelligence gain should accompany slighter gain in weight. In order to determine whether this was true for our cases, improvement in I.Q. was correlated with gain in weight, for the test group. The order of merit method was used, and the formula ρ = 1 - ((6ΣD_n) /( n(n²-1))) where f = 2 sin (Π/6)ρ. The resulting value of r was -·10 with unreliability of ·226, calculated by the formula σt.r - obt.r = (1·05(1-r²)) / √n. There is therefore no correlation between improvement in intelligence and gain in weight.

TABLE IX

Improvement in I.Q., 28 Pairs

N[16]	Test Group (A)			Control Group (B)
Test 1	Test 2	Gain	Test 1	Test 2	Gain
27	110	109	-1	72	96	24	-25
20	106	102	-4	118	131	13	-17
8	91	86	-5	98	104	6	-11
24	131	124	-7	89	92	3	-10
21	64	67	3	86	97	11	-8
3	94	91	-3	82	85	3	-6
12	98	95	-3	98	101	3	-6
23	85	94	9	81	96	15	-6
11	103	100	-3	101	102	1	-4
15	97	94	-3	78	79	1	-4
18	98	98	0	90	94	4	-4
4	96	96	0	83	85	2	-2
26	80	76	-4	90	88	-2	-2
16	65	73	8	74	82	8	0
28	81	84	3	95	98	3	0
5	95	99	4	114	117	3	1
2	107	114	7	91	96	5	2
10	110	109	-1	104	100	-4	3
17	71	77	6	96	99	3	3
7	91	99	8	95	99	4	4
1	82	83	1	80	76	-4	5
6	95	101	6	88	89	1	5
19	96	101	5	98	98	0	5
9	83	93	10	87	90	3	7
25	77	76	-1	145	137	-8	7
13	70	78	8	66	64	-2	10
22	91	100	9	63	62	-1	10
14	96	107	11	140	137	3	14
Av.	91·53	93·78	2·25	92·93	96·21	3·285	-1·035
M			2			-1	-0·015
75%ile			7			+·04	5
25%ile			-3			-·16	-6
Q			5			2·5	5·5
P. E. (distribution)			5·25			2·5	5
P. E. (average)			±·99			±·47	±1·10
						Av.= -·94 P. E.
						M.= -·99 P. E.

TABLE X

Improvement in Performance of Healy Test, 24 Pairs

N[16]	Test Group (A)			Control Group (B)
	Test 1	Test 2	Gain	Test 1	Test 2	Gain
7	- 6	-28	-22	4·5	27·5	23	-45
13	43	42	- 1	- 1·5	30·5	-32	-33
17	29·5	12	17·5	1·5	15	- 13·5	-31
15	7	25	18	1	42·5	41·5	23·5
26	22·5	7	-15·5	56	61·5	5·5	-21·5
10	-12	6·5	18·5	27	65	38	-19·5
19	57·5	49	- 8·5	-22	-11	11	-19·5
24	54·5	63	8·5	31·5	59·5	28	-19·5
20	0	-11	-11	30	35	5	-16
9	3·5	10·5	7	34	55	21	-14
11	-8	6	14	-29	-3·5	25·5	-11·5
16	49	47·5	- 1·5	30	37	7	- 8·5
1	-25	2	27	-50	-16	34	- 7
22	48·5	43·5	- 5	34·5	33·5	- 1	- 4
18	-13·5	-12	1·5	-32	-28	4	- 2·5
23	49·5	68	18·5	4	25	21	- 2·5
3	21·5	22·5	1	17	19	2	- 1
12	20	21	1	-10	-12	- 2	3
14	12·5	48·5	36	- 5	25·5	30·5	6·5
27	-25	15	40	2	27·5	25·5	14·5
2	28·5	30	1·5	3	-11	-14	15·5
25	8	25	17	29·5	29	-·5	17·5
21	20	32	12	70·5	58·5	-12	24
28	29·5	73·5	44	64·5	51·5	-13	57
Av.	17·29	24·94	7·64	12·12	25·69	13·56	- 5·85
M			4.25			- 7·75	-0·015
75%ile			18			+·04	3
25%ile			-5			-·16	-19·5
Q			11·5			13	11·25
P. E. (distribution)			10·6			10·56	13·65
P. E. (average)			±2·16			± 2·16	± 3·05
						Av.= -1·92 P. E.
						M.= -2·54 P. E.

Similarly, it might be thought that the children who had suffered from the defects for a comparatively short time, might reveal greater improvement in intelligence after six months than those who had been afflicted for a longer space of time. We had no way of knowing definitely how long the defects had been present in the cases studied. Roughly, though, we may say that in general the older boys have had defective tonsils and adenoids for a longer time than the younger ones, and that the older the boy, the older the defect. On this basis, if correlation of youth with gain in I.Q. should give a larger positive value for r, we might be justified in saying that the younger boys, who have been handicapped for a lesser period, show greater mental recuperation than their older companions. Such a correlation was attempted in the test group, correlating age at the first test with gain in I.Q. The same methods and formulae were used as in the weight and intelligence comparison, the greatest gain in I.Q. being given first position, and the lowest age. The resulting value for r was -·24, with an unreliability of ·186. The relationship would appear to be in the other direction but it is so small, with an unreliability measure so large as to be insignificant. Once more, then, we find in our results no correspondence between recency of defect and quick mental recovery.

TABLE XI

Showing percentile ratings of the members of the two groups at the beginning and end of the six months' interval

	Weight		Height		Grip		Tapping
1	·29	·44	·25	·40	·47	·40	·51	·33
1C	·43	·54	·27	·45	·33	·47	·17	·30
2	·04	·10	·04	·11	·16	·16	·16	·25
2C	·38	·55	·20	·32	·25	·40	·80	·28
3	·46	·59	·32	·49	·44	·56	·52	·58
3C	·65	·69	·74	·81	·54	·67	·51	·42
4	·33	·44	·39	·52	·16		·13
4C	·27	·32	·51	·78	·18		·19
5	·16	·20	·18	·20	·33		·23
5C	·50	·53	·28	·47	·40		·87
6	·12	·15	·06	·10	·10		·23
6C	·31	·40	·22	·38	·27		·41
7	·03	·07	·05	·15	·07	·06	·40	·27
7C	·01	·02	·03	·07	·16	·24	·16
8	·62	·71	·63	·75	·24		·27	·23
8C	·18	·37	·31	·40	·67	·72	·43	·11
9	·31	·41	·47	·53	·26	·47	·71	·51
9C	·60	·65	·76	·89	·76	·89	·63	·78
10	·26	·35	·26	·43	·44	·33	·01	·04
10C	·21	·22	·23	·37	·24	·67	·02	·51
11	·24	·23	·25	·43	·33	·67	·40	·08
11C	·08	·09	·09	·17	·36	·36	·86	·11
12	·25	·40	·15		·53		·08
12C	·06	·15	·02	·08	·04	·01	·12	·03
13	·95	1·00	·99	1·00	·99	1·00	·90	·66
13C	·87	·89	·93	·96	·94	·96	·78	·36
14	·49	·66	·67	·74	·72	·67	1·00	·57
14C	·92	·93	·96	·98	·93	·98	·97	·97
15	·56		·68		·70		·95	·94
15C	·79	·80	·59	·66	·67	·70	·62	·54
16	·49	·53	·74	·79	·81	·77	·69
16C	·34	·28	·50	·54	·24	·24	·69	·51
17	·53		·50		·53		·05	·78
17C	·17		·15		·24	·11	·40	·34
18	·57		·38		·33		·45	·51
18C	·17	·20	·30	·34	·10	·06	·09	·03
19	·95	·99	·94	·98	·94	·88	·93
19	·38	·45	·30	·37	·67	·40	·09	·31
20	·13		·37		·33		·16	·23
20C	·63	·75	·56	·88	·67	·44	·78	·86
21	·83	·89	·84		·76	·76	·80	·44
21C	·67	·77	·55	·61	·81	·67	·62	·57
22	·85		·81	·91	·78	·95	·92	·99
22C	·83	·92	·93	·97	·82	·91	·33	·89
23	·36		·45		·36	·70	·78	·63
23C	·73	·74	·70	·82	·55	·53	·36	·62
24	·59	·69	·67		·81	·85	·89	·66
24C	·62	·63	·59	·71	·67	·67	·86	·86
25	·47	·60	·57	·63	·53		·62	·78
25C	·73	·74	·60	·64	·44	·91	·70	·79
26	·74	·89	·74	·85	·53		·54	·57
26C	·76	·81	·70	·79	·84	·76	·40	·40
27	·11		·23		·16	·04	·18	·06
27C	·07	·12	·12	·23	·10	·16	·30	·25
28	·86	·90	·87	·90	·97	·88	·78	·91
28C	·87	·93	·83	·86	·88		·98	·94

TABLE XI (Continued)

Showing percentile ratings of the two groups at the beginning and end of the six months' interval

N[16]	I.Q.		Healy		Total	Possible	Average
							Gain
1	·25	·27	·10	·29	·30	415	·05
1C	·21	·15	·01	·12	·53	462	·089
2	·84	·89	·60	·66	·38	416	·063
2C	·45	·51	·29	·18	-·07	358	-·011
3	·49	·44	·49	·51	·40	328	·066
3C	·25	·32	·44	·45	·30	287	·05
4	·59	·59	·38		·22	168	·073
4C	·27	·32	·71		·42	195	·14
5	·53	·71	·10		·42	213	·14
5C	·89	·90	·77		·24	133	·08
6	·53	·77	·02		·55	229	·183
6C	·37	·38	·04		·27	210	·09
7	·45	·71	·22	·07	·37	478	·062
7C	·53	·71	·34	·59	·74	393	·148
8	·45	·34	·70		-·50	303	-·125
8C	·67	·81	·33	·52	·10	241	·025
9	·27	·46	·23	·39	·71	375	·118
9C	·35	·40	·73	·89	·72	217	·12
10	·88	·86	·15	·35	·34	400	·056
10C	·81	·73	·57	·97	1·39	392	·218
11	·79	·73	·20	·34	·21	379	·035
11C	·77	·79	·05	·23	-·44	379	-·073
12	·67	·53	·47	·49	-·11	161	-·036
12C	·67	·77	·19	·15	·19	208	·032
13	·09	·19	·79	·78	·02	129	·003
13C	·06	·05	·24	·67	·06	178	·01
14	·59	·84	·41	·84	·69	212	·115
14C	·97	·96	·21	·56	·41	104	·068
15	·62	·49	·38	·55	·12	106	·04
15C	·19	·20	·26	·79	·66	193	·11
16	·05	·12	·86	·82	·15	205	·03
16C	·13	·25	·66	·76	·24	313	·04
17	·09	·17	·63	·40	·66	223	·220
17C	·59	·71	·27	·43	·21	174	·053
18	·67	·67	·13	·15	·08	175	·027
18C	·40	·49	·04	·07	·18	247	·03
19	·59	·69	·91	·85	·16	67	·032
19C	·67	·67	·11	·18	·16	287	·027
20	·82	·79	·25	·18	-·06	177	-·02
20C	·91	·94	·66	·75	·20	65	·066
21	·05	·07	·47	·69	-·16	209	-·032
21C	·34	·62	·99	·92	·46	157	·077
22	·45	·73	·84	·81	·87	120	·174
22C	·03	·02	·74	·72	·74	275	·123
23	·32	·49	·86	·98	·65	168	·163
23C	·23	·59	·33	·50	1·26	253	·21
24	·94	·92	·88	·95	- ·06	89	-·012
24C	·38	·46	·68	·93	·54	179	·09
25	·17	·15	·37	·55	·49	280	·098
25C	1·00	·97	·63	·60	·53	134	·088
26	·21	·15	·51	·36		226 0
26C	·40	·37	·90	·94	·04	184	·007
27	·88	·86	·10	·43	·05	268	·013
27C	·11	·59	·29	·59	1·49	320	·25
28	·23	·29	·63	1·00	·59	153	·097
28C	·53	·67	·96	·87	·24	83	·048

Table XI expresses the results of Table II, with the scores given in percentile values. In each test, the group was taken as composed of the two scores of every individual—the total number of scores in tests and retests, eliminating those scores where the other member of the pair was lacking, or where no retest was given. Thus case number 1 was just within the lowest 27% of the group in weight at the first weighing, but had advanced to the 44 percentile at the second. In height he gained from the 25 percentile to the 40 percentile. His total gain in all tests is 30 percentile out of a possible 415, and the average gain is ·05. The reader may see by scanning the table that the gains in the test group are practically equaled by those in the control group. There seems to be no consistent relationship between a low score in the first test and a large gain. This is true even though the method of calculation tends to minimize gains at the high end of the group, and losses at the low end. In table XII this may be seen more clearly in respect to I.Q. and the results for all the tests taken together with the I.Q. weighted by being counted twice. A large possible gain indicates that the score at the first testing was low, and vice versa. Considering I.Q. values, the largest possible gain in the test group was 95 per cent of the group. This occurred twice, in one case the actual gain being 7% of the group and in the other 2%. In the control group, the largest possible gain was 97% of the group, but actually this case fell 1% of the group. If we correlate possible gain with actual gain for each group, using the formula r = 2sin((Π/6)ρ)) when ρ = 1 - ((6ΣD²)/(n(n²-1))) we get a coefficient of correlation ·36 in the test group, and ·19

TABLE XII

Showing gains in percentile rating for I.Q., and for a total of all the tests with I.Q. weighted by being counted twice.

	I.Q.				Total
			A	B
	1st P.R.	2d P.R.	possible gain	actual gain	possible gain	actual gain	Av. Gain
1	25	27	75	2	415	30	5
1C	21	15	79	-6	462	53	8·9
2	84	89	16	5	416	38	6·3
2C	45	51	55	6	358	- 7	-1·1
3	49	44	51	-5	328	40	6·6
3C	25	32	75	7	287	30	5
4	59	59	41		168	22	7·3
4C	27	32	73	5	195	42	14
5	53	71	47	18	213	42	14
5C	89	90	11	1	133	24	8
6	53	77	47	24	229	55	18·3
6C	37	38	63	1	210	27	9
7	45	71	55	26	478	37	6·2
7C	53	71	47	18	393	74	14·8
8	45	34	55	-11	203	-50	-12·5
8C	67	81	33	14	241	10	2·5
9	27	46	73	19	375	71	11·8
9C	35	40	65	5	217	72	12
10	88	86	12	-2	400	34	5·6
10C	81	73	19	-8	392	139	21·8
11	79	73	21	-6	379	21	3·5
11C	77	79	23	2	379	-44	-7·3
12	67	53	33	- 6	161	- 11	- 3·6
12C	67	77	33	10	208	19	3·2
13	9	19	91	10	129	2	·3
13C	6	5	94	- 1	178	6	1
14	59	84	41	25	212	69	11·5
14C	97	96	3	- 1	104	41	6·8
15	62	49	38	-13	106	12	4
15C	19	20	81	1	193	66	11
16	5	12	95	7	205	15	3
16C	13	25	87	12	213	24	4
17	9	17	81	8	223	66	22
17C	59	71	41	12	174	21	5·3
18	67	67	33		175	8	2·7
18C	40	49	60	9	247	18	3
19	59	69	41	10	67	16	3·2
19C	67	67	33		287	16	2·7
20	82	79	18	- 3	177	-6	- 2
20C	91	94	9	3	65	20	6·6
21	5	7	95	2	209	- 16	- 3·2
21C	34	62	66	28	157	46	7·7
22	45	73	55	28	120	87	17·4
22C	3	2	97	- 1	275	74	12·3
23	32	49	68	17	168	65	16·3
23C	23	59	77	36	253	126	21
24	94	92	6	- 2	89	-6	- 1·2
24C	38	46	62	8	179	54	9
25	17	15	83	- 2	280	49	9·8
25C	100	97		- 3	134	53	8·8
26	21	15	79	- 6	226
26C	40	37	60	- 3	184	4	·7
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-Weight	Grip	Tapping	Tapping fatigue	I.Q.	Healy
	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	0.00	-2·54

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