LB ca ; .vu^; 3 B.i-V/\\\ N w < \^ Si V v. K \\< t: i £ A\ \ v Vr. W 'A TREASURY DEPARTMENT UNITED STATES PUBLIC HEALTH SERVICE HUGH S. CUMMING, Surgeon General SICKNESS AMONG SCHOOL CHILDREN LOSS OF TIME FROM SCHOOL AMONG 6,130 SCHOOL CHILDREN IN 13 LOCALITIES IN MISSOURI BY SELWYN D. COLLINS ii Assistant Statistician United States Public Health Service REPRINT No. 674 FROM THE PUBLIC HEALTH REPORTS July 8, 1921 (Pages 1549-1559) 2|-24^ri WASHINGTON GOVERNMENT PRINTING OFFICE 1921 MOiKtf. \». SICKNESS AMONG SCHOOL CHILDREN. Loss of Time From School Among 6,130 School Children in 13 Localities in Missouri. 1 By Selv?tn D. Collins, Assistant Statistician, United States Public Health Service. At the present stage of our knowledge of disease problems, any records which show the true incidence of even a few diseases in an observed population are important. Ordinary morbidity reports as furnished by physicians to local health departments do not, for well- known reasons, give an accurate picture of the incidence of any disease in a definitely enumerated population group. It is necessary, therefore, to utilize other methods for obtaining the desired informa- tion. In a general way, the most promising directions for seeking data of this character are: (1) Records of disability among groups of in- sured persons associated in various kinds of sick-benefit associations; (2) records of sickness in groups of persons employed in industrial establishments where careful medical supervision and a system of disability records have been established; (3) records of sickness in groups of individuals living in institutions or attending school; and (4) special surveys of population groups made for the specific purpose of ascertaining the incidence of a given disease or group of diseases. In various prior publications the Public Health Service has pre- sented statistics of disability among adult wage earners who are mem- bers of sick-benefit associations, and the results of special sickness surveys. In the hope of obtaining data regarding the incidence of diseases among children, an attempt was made in connection with the field studies in child hygiene in Missouri during 1919-20, to insti- tute a system of sickness records in connection with the schools. This was undertaken purely as an experiment, and a limited number of schools were requested to cooperate with the Public Health Service for this purpose. The results are presented in the following pages. The work is being undertaken on a larger scale, not only in Missouri but in other States for the school session of 1921-22. The data here presented were collected in 13 localities in the State of Missouri. These data were entered by the teachers on cards dis- i from Field Investigations in Child Hygiene, United States Public Health Service. The statistical part of this study was conducted in the Statistical Office of the Public Health Service. Reprint from the Public Health Reports, vol. 36, No. 27, July 8, 1921, pp. 1549-1559. 9 63631°— 21 LIBRARY Of C0N3RI88 JK&ilVID 0OOUMENT8 Dl i idlQN SICKNESS AMONG SCHOOL CHILDREN. 6 tributed by medical officers of the Public Health Service in charge of child hygiene studies in the several communities. A card was made out for each child, showing sex, color, and age, and record, by school months, of the total possible number of days of school attendance, 1 the days present, the days absent on account of sickness, and the days absent from causes other than sickness. The card also con- tained a record of the diseases the child had during each month of the session. After the cards had been completed and collected, they were care- fully edited for errors, and only those which seemed to be properly and accurately used were included in the tabulation. It is believed that the necessary selection of properly filled out cards did not elimi- nate a disproportionate number of any particular class, such as those showing an excessive amount of absence or attendance. The records, even after careful editing, however, can be consid- ered only as 9 preliminary experiment. The data were incomplete in many ways. Records showing the specific data desired on the card were kept only after the first of the year 1920, and in some localities they were begun even later. Data for the months prior to the beginning of any special records were taken from the regular school records and, therefore, vary in completeness in the different localities. The entries showing the specific diseases causing the absence were not complete; in the majority of cases the number of days absent because of sickness was shown without speci- fying the disease. It was therefore decided to compute only the per- centages of the total possible days of school attendance which were lost on account of sickness of all kinds and of causes other than sick- ness, with certain other data based on those cards reporting the spe- cific disease causing the absence. Table I shows the size and location of the cities from which data were drawn. They range from one to twenty thousand in population, and are fairly representative, average-sized cities of the State. No data from the larger cities were included. 1 It was found that, according to the prevailing custom in keeping school records of enrollment, a child's name was dropped from the roll after three days' absence and reentered when he returned. In tabulating the records for the purpose of counting the absence from school on account of sickness, a child's name was not dropped from the roll except when he was permanently separated from the school, as in the case of a child who left the community, or who went to work, or some similar case. With this difference, the total possible number of days of school attendance is the total number of days enrolled during the period used for the computation. SICKNESS AMONG SCHOOL CHILDREN. Table I. — Population and location of certain cities in Missouri and the number of chil- dren for whom, sickness records were obtained in each place. City. County. Popula- tion of city. 1920. Number of children included. Sedalia Pettis . Jellerson City Cole. Independence Cape Girardeau Warrensburg Excelsior Springs Bonne Terre West Plains Liberty Farmington Jackson Montgomery Oregon Jackson Cape Girardeau. Johnson Clay St. Francis Howell Clay St. Francis Cape Girardeau . Montgomery Holt 21,144 14,490 11,686 10, 252 4, Ml 4,165 3,*15 3,178 3,097 2,685 2,114 1,68S 904 1,367 660 969 230 446 302 641 436 351 421 154 16 137 Table II, computed from the basic data shown in Table VII (see appended tables), shows by months the percentages of the total possible number of days of school attendance whiqji were lost on account of sickness and of causes other than sickness. The data are shown by sex and for two age groups. Table II. — Percentages of total possible number of days of school attendance which wext lost on account of sickness and of causes other than sickness for each month of the school year 1919-20, in certain localities in Missouri. 1919 1920 Cause of absence, Total sex, and age group. year. Septem- ber. Octo- ber. Novem- ber. Decem- ber. Janu- ary. Febru- ary. March. April. May. Sickness: Both sexes- All ages (6 to 18) 5.6 1.3 2.5 4.2 5.5 6.3 11.6 6.9 5.8 3.6 6tol0 6.9 1.3 3.0 5.4 6.7 7.5 13.9 8.9 7.6 4.7 11 to 18) 4.1 1.3 2.0 2.9 4.2 4.9 9.0 4.7 4.0 2.4 Boys- All ages (6 to 18) 5.4 1.2 2.3 4.0 4.8 6.1 11.9 6.6 5.8 3.2 6tol0 6.7 1.2 2.7 5.0 5.7 7.4 14.0 8.7 7.5 4.1 11 to 18 3.9 1.2 2.0 3.0 3.8 4.5 9.5 4.3 3.8 2.3 Girls- All ages (6 to 18) 5.8 1.4 2.7 4.4 6.2 6.6 11.4 7.2 5.9 4.0 6tol0 7.2 1.4 3.3 5.8 7.6 7.7 13.8 9.1 7.7 5.3 11 to 18 4.2 1.4 1.9 2.9 4.6 5.3 8.6 5.1 4.1 2.6 Other causes: Both sexes- All ages (6 to 18) 3.0 2.0 2.5 2.6 3.3 3.1 4.0 3.2 2.9 2.7 6 to 10 2.9 2.2 2.8 2.6 3.4 3.3 3.9 2.8 2.5 2.6 11 to 18 3.1 1.9 2.2 2.6 3.2 3.0 4.1 3.6 3.3 2.8 Boys- All ages (6 to 18) 3.2 2.2 2.8 2.6 3.7 3.4 4.4 3.5 3.1 3.1 6tol0 3.1 2.2 3.2 2.7 3.8 3.6 4.3 3.0 2.6 2.8 11 to 18 3.4 2.2 2.3 2.6 3.6 3.1 4.6 4.0 3.8 3.4 Girls- All ages (6 to 18) 2.7 1.9 2.2 2.5 2.9 2.9 3.6 2.9 2.6 2.3 6tol0 2.6 2.2 2.3 2.5 3.0 3.0 3.5 2.6 2.4 2.3 11 to 18. .. 2.7 1.5 2.1 2.5 2.8 2.9 3.7 3.3 2.8 2.2 As between the sexes, absence on account of sickness is, with some exceptions, greater for girls than for boys. The differences, however, are so small that they can hardly be considered significant. The SICKNESS AMONG SCHOOL CHILDEEN. absence from causes other than sickness is greater for boys than for girls in practically all cases. Although the differences are not great, they persist in all months and therefore seem to indicate that causes other than sickness were responsible for a greater amount of ab- senteeism among boys than among girls. From the point of view of age, the younger group seems to lose more time because of sickness than the older group. The percent- ages of total possible days of attendance which were lost on account Percentages or Total Possible Days of School Attendance Which Were Lost on Account of Sickness and of Causes Other Than Sickness For Each Month of The School Year I9I9-20 Bv Children in Certain Localities in Missouri Sepiember|Octob«r |Nov«mbar|Decembar Jeurm.n.r\f [February! Mtifcti | April | May 5 8 of sickness is greater for the younger group in practically all cases. The differences are large enough to be significant and suggest one of three things : that a larger number of cases of sickness occurred among the younger children, or that they recovered more slowly, or that they were kept at home for less serious illness or for a longer time after recovery than was the case with the older children. Unfortunately, the data available for this study were not in such a shape that the question could be settled as to which was actually the case. Absence from causes other than sickness seems to differ less for the two age groups than absence from sickness. For the year as a whole, the children of the older group were absent slightly more from causes other than sickness than were those of the younger group. As to the seasonal distribution of such absence, the younger group seems to have more absence in the first half of the year, but less in the last half. However, the differences are too slight to be signifi- cant; but since the tendency is so general and applies to all groups, it is worth noting. 6 SICKNESS AMONG SCHOOL CHILDREN. Figure I shows, for both sexes and all ages, the percentages of time lost from school because of sickness and of causes other than sickness for each month of the school year. The unusually high peak in February, 1920, is obviously due to the influenza epidemic. Of the days lost on account of sickness from known diseases in that month, 46 per cent were due to influenza, and 34 per cent of the cases of illness of known cause were due to influenza. Reference to Table IV will show that the percentages of days lost and of cases of influenza were not large except in January and February; the curve, therefore, approximates sickness in a normal year except for those months. In view of the consistently greater time lost on account of sickness by the younger of the two age groups, Table III was prepared to show the time lost on account of sickness and of causes other than sickness for children of each year of age from 6 to 16 years, inclusive, for the school session. The data are presented graphically in Figure 2. Table III. — Time lost from school on account of sickness and of other causes, by children each year of age from 6 to 16 years, inclusive, during the school year 1919-20, in certain localities in Missouri. Age in years. Total pos- Number of ^rl^'s children. : b «[ s ° c f h d £f attendance. Percentage of total possible days of school at- tendance lost on ac- count of sickness. Percentage of total possible days of school at- tendance lost on ac- count of other causes. All ages (6 to 16) : 6, 099 666, 449 5.6 3.0 6 404 627 651 745 741 754 731 618 475 261 92 49, 480 65, 157 67,605 84, 764 83,627 84,982 80,083 62,246 61, 040 26,425 9,040 9.7 8.6 6.7 6.1 4.9 4.0 4.2 4.0 3.6 4.9 3.9 3.8 7 3.0 8 •. 2.8 9 2.5 10 2.6 11 2.3 12 3.1 13 3.0 14 2.9 15 3.9 16 3.3 The time lost from sickness shows no great variations nor any consistent trend from 11 to 16 years of age, but decreases considerably and consistently from 6 to 11 years. Absence from causes other than sickness shows no marked differences for the different ages. If any trend whatever is shown, it indicates increasing absence for the older children, but the items are irregular and the increasing trend is slight only. The specific diseases causing absence were reported in 2,326 cases, resulting in 14,373 days' absence from school (see appended Tables VIII and IX). On the basis of these known cases, cer- tain computations were made as to the relative importance of certain diseases as a cause of absence in each month of the school year. Because of the fact that the influenza epidemic made certain SICKNESS AMONG SCHOOL CHILDREN. i » jo o u) 33*3 »i3y J.BO-J SAVQ sp|<»0 ■"'.-"•w^'.a b^s^ — "-m m m i aa a B iif 36V1N30B3IJ " r» 36yiN33aB(j 8 SICKNESS AMONG SCHOOL CHILDREN. months of this school year exceptional, the cases of and the absences due to influenza were deducted from this total number, and the pro- portion of cases of and of days lost from all diseases, exclusive of influenza, were computed for each disease for each month of the school year. For example, absence because of sickness of known cause in March was 2,528 days; but of this total, 223 days were due to in- fluenza, leaving 2,305 days due to other known diseases. Of this total absence from known diseases, 543 days, or 23.6 per cent, were due to measles. Similar percentages were worked for other diseases and for each month to show the relative importance of certain diseases in causing absence from school at different seasons of the year after eliminating the abnormal condition resulting from influenza. Table IV shows the results of these computations. Table IV. — Percentages of total number of days lost from school on account of all illness of known cause (exclusive of influenza) , and percentages of total cases of illness ofknoivn cause (exclusive of influenza) due to certain diseases, among children 6 to 18 years of age, in certain localities in Missouri during 1919-20. Total school ye«r 1019 1920 Disease. Sep- tember. Octo- ber. Novem- ber. Decem- ber. • an- uary. Febru ary. March. April. May. PERCENTAGE DUE TO EACH DISEASE. Days lost: All diseases (ex- clusive of in- fluenza) Colds 100.0 32. 5 23.5 12.8 7. 5 4.4 3 6 2.6 2.3 2.3 .8 i\ 2 100.0 57.0 12.1 10.3 2.8 1.1 2.7 2. } .7 6.1 .3 _ 2 i's 100.0 47.1 100.0 41.3 100.0 34.1 100. 50.8 .8 2.6 19.7 7.7 3.2 2.8 1.8 3.4 100.0 52.3 .4 16.2 7.4 4.4 2.7 2.3 5.1 2.2 100.0 33.0 16.0 11.6 5.9 5.4 6.9 3.1 5.0 3.0 .9 .7 8.5 100.0 56. 1 8.7 10.1 2.5 1.7 4.8 3.1 .8 6.2 .3 .6 5 1 100.0 33.1 23.6 19.7 2.7 3.6 4.5 2.2 1.9 1.8 .9 6.0 100.0 58. 9 11.5 13.8 .7 .7 3.5 2.8 5.4 .2 4.5 100.0 10.7 54.7 15.3 .7 . 5 .7 2.5 1.1 2.2 .7 .2 4.7 100.0 36. 33.1 13.5 .3 .3 .8 2.2 1.1 7.8 .3 4.0 100.0 15.6 48.1 14.3 "2.T 1.4 30.1 5.9 2.3 1.0 1.4 3.0 1.4 29.4 7.8 9.7 3.5 1.3 3.3 2.0 13.6 Scarlet fever .... Whooping cont'h Chicken pox .... Tonsillitis Pneumonia Toothache Diphtheria. . . .7 6.6 2.8 2.1 1.4 Other diseases... Cases: All diseases (ex- clusive of in- Colds 36.5 100.0 71.2 13. 6 100.0 70.1 7.5 100.0 61.0 7.2 100.0 75.3 .5 3.0 7.1 .5 2.5 1.5 7.0 100.0 72.6 .3 10.7 2.2 .9 1.9 2.2 1.9 3.8 8.6 100.0 41.0 27.7 """'fi.'s' 3.2 1.3 9.1 2.6 1.3 1.3 1.3 9.1 1.6 13.0 i.e 6.5 2.4 15.1 Scarlet fever.. . . TV hoopiiv.' eoiirh Chicken pox. . . Tonsillitis 2.4 2.4 Toothache 9.0 .8 4.6 1.0 7.2 .6 .6 Other diseases... 16.1 3.9 4.1 4.0 3.5 3.0 PERCENTAGE OF TOTAL DAYS LOST FROM ILLNESS OF KNOWN CAUSE AND TOTAL CASES OF ILLNESS OF KNOWN CAUSE DUE TO INFLUENZA Days lost: Influenza. Cases: Influenza. 17.7 3.6 2.1 4.6 IS. 1 46.3 8.8 2 8 11.2 3.1 1.6 3.9 12.2 33.9 3.8 1.9 SICKNESS AMONG SCHOOL CHILDREN. 9 It is a striking fact that colds were the greatest single assigned cause of absence in every month of the school year. The other infec- tious diseases are more or less seasonal in character; measles was an important cause of absence from February to May, scarlet fever from September to December. Seasonal variation was not such an out- standing fact in the other cases, but existed for most of the common infectious diseases. Children are more disposed to some diseases at certain ages, and therefore the relative importance of those diseases as causes of absence from school varies with age. In order to show this variation, Tables V and VI were prepared, showing by age groups the percentages of the total number of days lost from sickness of known cause which were due to certain diseases. Similar computations were made for the percentages of cases and the days lost per case of these diseases. Table V. — Percentage of days lost from diseases of known caiise and of cases of illness of known cause due to certain diseases among children in certain localities in Missouri, by age groups. Disease. Days lost. All ages (6 to 18). 6 to 10 years of 11 to IS years of age. Cases. All ages (6 to 18). 6 to 10 years of age. 11 to 18 years of PERCENTAGE OF ALL ILLNESS FROM KNOWN CAUSE (EXCLUSIVE OF INFLUENZA) DUE TO CERTAIN DISEASES. All diseases (exclusive of influenza). Colds Measles Mumps Scarlet fever Whooping cough. Chicken pox Tonsillitis Toothache ,. Pneumonia Diphtheria Smallpox Other diseases 100.0 32.5 23.5 12.8 7.5 4.4 3.6 2.6 2.3 2.3 100.0 28.4 28.6 12.0 8.2 6.3 4.2 1.4 1.6 2.2 .5 .6 6.0 100.0 41.0 12.9 14.5 6.0 .3 2.5 5.0 3.8 2.4 1.4 .4 9.S 100.0 57.0 12.1 10.3 2.8 1.1 2.7 2.4 6.1 .7 .3 .2 4.3 100.0 52.8 16.7 10.9 3.2 1.7 3.5 1.3 5.0 .7 .2 .2 3! 8 100.0 63.2 5.5 9.5 2.3 .1 1.4 4.0 7.8 .7 .4 .1 5.0 PERCENTAGE OF ALL ILLNESS FROM KNOWN CAUSE DUE TO INFLUENZA. Influenza. 17.7 16.0 21.0 11.2 10.5 10 SICKNESS AMONG SCHOOL CHILDREN. Table VI.- - Average number of days lost Jrom school per case of certain diseases among children in certain localities in Missouri, by age groups. Disease. All ages (6 to 18). 6 to in years of 11 to 18 years of age. All diseases Whooping cough Pneumonia Diphtheria Scarlet fever Smallpox Measles Influenza Chicken pox Mumps Tonsillitis Colds Toothache Other diseases... 6.2 23.5 19.2 15.9 15.1 14.5 11.1 9.7 7.8 7.1 6.2 3.3 2.2 9.6 24.1 22.1 14.0 16.5 14.3 11.2 10.5 7.7 7.1 7.1 3.5 2.1 10.2 5.1 9.5 15.3 17.8 12.2 15.0 10.7 8.8 7.8 7.1 5.8 3.0 2.2 8.9 Figure 3 shows graphically the relative importance of these diseases as measured in days lost and in cases of illness among children of 6 to 18 years of age, inclusive. Figure 4 shows the severity of cases of various diseases as measured in the average time lost from school per case. For the year as a whole, the children lost, on account of sickness, an average of 5.6 per cent of the days that school was in session. Assuming that this percentage of days of sickness is representative of the whole year, it means an average of slightly over 20 days of sickness per child per year. Boys were absent on account of sickness almost as much as girls, the difference being only 0.4 of 1 per cent, which, on an annual basis, would mean about 20 days of sickness for boys and about 21 for girls. The data presented here are, of course, insufficient to afford con- clusions of a general nature, but it is believed that they do suggest that the use of school records for obtaining facts as to disease inci- dence among children is practicable. Such facts, it is unnecessary to say, would be of great value, not only to those who are interested in epidemiology, but to school and health administrators. SICKNESS AMONG SCHOOL CHILDREN. 11 Table VII. — Number of children included in the study, total possible number of days of school attendance, and days absent on account of sickness and of causes other than sick- ness, by months, for the school year 1919-20, in certain localities in Missouri. Aee and sex. All ages: Both sexes- Number of children . . . Total possible days of school attendance . . . Days absent — Sickness Days absent — Other causes Boys- Number of children Total possible days of school attendance Days absent — Sickness Days absent— Other causes Girls- Number of children Total possible days of school attendance — Days absent — Sickness Days absent— Other causes 6 to 10 years: Both sexes — Number of children Total possible days of school attendance Days absent — Sickness Days absent — Other causes Boys- Number of children . . . Total possible days of school attendance Days absent — Sickness . Days absent — Other causes Girls- Number of children Total possible days of school attendance Days absent— Sickness . Days absent— Other causes 11 to 18 years: Both sexes- Number of children Total possible days of school attendance Days absent— Sickness . Days absent — Other causes Boys- Number of children Total possible days of school attendance Days absent — Sickness. Days absent — Other causes Girls- Number of children Total possible days of school attendance Days absent— Sickness . Days absent — Other causes Total school year. 6, 130 669, 214 37, 368 19, 802 2,870 325, 150 17,442 10, 555 3,260 344, 064 19, 926 3,173 351, 313 24, 413 10, 078 1,497 170,611 11, 352 5,300 1,676 180, 702 13, 061 4,778 2, 957 Sept. Oct. Nov. Dec 317, 901 12, 955 9,724 1,373 154, 539 6,090 5,255 1,584 163, 362 6,865 4,469 2,701 54, 020 717 1, 1,332 26, 640 326 583 1,369 27, 380 391 516 28,420 376 623 692 13,840 167 303 729 14, 5S0 209 1, 280 25,6(10 341 476 640 12, 800 159 280 640 12,800 182 196 55, S60 1,101 1,402 1,382 27,640 646 769 1,411 28, 220 755 1,476 29, 520 884 813 720 14, 400 384 460 756 15, 120 500 1,317 26, 340 517 13,240 262 309 655 13, 100 255 57, 120 2,422 1,470 1,413 28, 260 1,138 744 1,443 28, S60 1,284 726 30, 320 1,634 14, 860 737 400 773 15, 460 897 1,340 26,800 788 683 670 13, 400 401 344 670 13,400 387 339 2,920 58, 400 3,219 1,915 1,447 28, 940 1,396 1,066 1,473 29, 460 1,823 1,542 30, 840 2,059 1,035 753 15,060 863 567 789 15, 780 1,196 468 1,378 27, 560 1,160 694 13, S80 533 13, 680 627 381 3,340 66, 700 4,226 2,094 1,650 33,000 2,000 1,111 1, 33, 700 2,226 36, 160 2,724 1,186 885. 17, 700 1,305 638 923 18, 460 1,420 548 1,532 30, 540 1, 502 908 765 15,300 695 473 767 15,240 806 60S 1,923 3S, 460 5,347 1,507 946 18,920 2,649 814 977 19, 540 2,69S 693 1,685 33, 700 3,044 1,395 833 16, 600 1,579 761 852 17, 040 1,465 Mar. Apr. May 764 5,494 1,674 2,801 56, 244 4,991 1, 570 1,322 26, 576 2,299 800 1,479 29, 668 2,692 770 2,547 51, 521 2, 433 1, 1,190 24, 025 1,034 964 1,357 27, 496 1,399 1,513 56,496 4, 290 1, 408 1,375 27,552 2,065 706 1,446 28, 944 2,224 702 2,673 53, 773 2,140 1,754 1,249 25,081 964 943 1,424 28, 692 . 1, 177 4,377 86,920 3,138 2,320 2,115 41, 856 1,346 1,294 2,262 45,064 1,792 1,026 2,229 44,853 2,108 1,149 1,091 21, 703 883 612 1,138 23, 150 1,225 537 2,148 42, 067 1, 030 1,171 1,024 20, 153 463 682 1,124 21, 914 567 12 SICKNESS AMONG SCHOOL CHILDREN. Table VIII. — Number of days lost from school on account of sickness of known cause and number of cases of known diseases among school children 6 to 18 years of age, in certain localities in Missouri during 1919-20. l Total school year. 1919 1920 Disease. Septem- ber. Octo- ber. Novem- ber. Decem- ber. Janu- ary. Feb- ruary. March. April. May. Days lost: All known dis- 14,373 11,832 2,541 2,326 2,065 261 98 95 3 32 31 1 356 356 77 77 793 777 16 125 123 2 1,176 1,122 54 206 198 8 1,764 1,445 319 361 317 44 4,008 2,154 1,854 537 355 182 2,528 2.305 223 444 427 17 2,533 2,461 72 378 1,117 All known dis- eases (exclu- sive of influ- 1,117 Influenza Cases: All known dis- lfifi All known dis- eases (exclu- sive of in flu- 371 166 7 1 Data given here are for only the small part of the total absence from sickness in which the specific dis- ease was reported. Table IX. — Number of days lost from school on account of sickness of known cause and number of cases of each known disease causing absence among children 6 to 18 years of age, in certain localities in Missouri during 1919-20. 1 Disease. All known diseases All known diseases (exclusive of influenza) Influenza Cold Measles Mumps Scarlet fever Whooping cough Chicken pox Tonsillitis Toothache Pneumonia Diphtheria Smallpox Other diseases Days lost. All ages (6 to 18). 14, 373 11,832 2,541 3,843 2,785 1,512 891 516 427 305 275 269 96 58 855 6 to 10 years of 9,523 8,001 1,522 2,273 2,290 955 659 506 333 113 129 177 42 43 481 11 to 18 years of age. 4,850 3,831 1,019 1,570 495 557 232 10 94 192 146 92 54 15 374 Cases. All ages (6 to 18). 2,326 2,065 261 1,177 251 213 59 22 55 49 126 14 6 4 6 to 10 years of age. 1,376 1,231 145 650 205 134 40 21 43 16 61 8 3 3 47 11 to 18 years of 950 834 116 527 46 79 19 1 12 33 65 6 3 1 42 1 Data given here are for only the small part of the total absence from sickness in which the specific dis- ease was reported. ADDITIONAL COPIES OF THIS PUBLICATION MAY BE PROCURED FROM THE SUPERINTENDENT OF DOCUMENTS GOVERNMENT PRINTING OFFICE WASHINGTON, D. C. AT 5 CENTS PER COPY V