HH 1335 D8 8 •IB 1335 .08 *opy 1 The Improvement of Statistics of Cause of Death Through Supplementary Inquiries to Physicians Reprinted from the Quarterly Publications of the American Statistical Association, June, 1916 BY LOUIS I. DUBLIN, Statistician EDWIN W. KOPF, Chief Clerk Statistical Bureau, Metropolitan Life Insurance Company, New York * ft o ■b { ^ % By Transfer NOV 3 1916 47] Statistics of Causes of Death. 175 THE IMPROVEMENT OF STATISTICS OF CAUSE OF DEATH THROUGH SUPPLEMENTARY INQUIRIES TO PHYSICIANS. By Louis I. Dublin, Statistician, and Edwin W. Kopf, Chief Clerk, Statis- tical Bureau, Metropolitan Life Insurance Company, New York. The extension of the registration of vital statistics and the consequent increase in the amount of available data on Ameri- can mortality have resulted in recent years in the development of a critical spirit toward these statistics. When data were scant, they were perforce accepted with little or no question; today we are justified in inquiring to what extent the returns are an accurate picture of the actual conditions. Perhaps enough material is now at hand to enable one to separate the probably true from the uncertain in our mortality returns. This questioning is clearly warranted by the likelihood that the sources of our statistics will thus be improved. It is only as our basic material is sound that the death rates we quote have real value. The chief source of error in the statistics of mortality is, of course, the uncertainty of the primary diagnosis made by the physician certifying to the cause of death. A group of clini- cians and pathologists, represented by Cabot,* Oertel,f and Emerson,| have in recent years contributed stimulating and constructive studies of the general reliability of diagnoses made in fatal cases. These writers point out, for example, that the acute infections, like typhoid fever, scarlet fever, and diphtheria, and those conditions which are usually of long duration and present distinct clinical pictures, like pulmonary tuberculosis and the external cancers, furnish no special dif- ficulties of diagnosis to the physician, and statements with regard to them may be accepted without further question. On the other hand, bedside diagnoses, even in our best hospi- • Cabot, Richard C, M.D.: Diagnostic Pitfalls Identified during a Study of Three Thousand Autopsie, Journal Amer. Medical Ass'n, December 28, 1912. f Oertel, Horst, M.D.: The Inaccuracy of American Mortality Statistics, American Underwriter, May, 1913. J Emerson, Haven, M.D.: Reliability of Certain Classes of Death Certificates, Amer. Jour. Public Health, August, 1915. 176 American Statistical Association. [48 tals, of Bright's disease, of cerebral hemorrhage and apoplexy, and of certain of the heart affections are very frequently not confirmed by autopsy, while other determinative conditions are shown to have been the primary cause of death. Relief from this fundamental difficulty is not within the control of stat- isticians, but will depend entirely upon the improvement of autopsy facilities and the general rise of standards of medical education. A Committee of the Vital Statistics Section of the American Public Health Association is now actively engaged in considering the International List of Causes of Death from this point of view, registering its conclusions as to those titles which can be accepted with considerable certainty even in the absence of an autopsy, as against those which must be con- sidered as tentative assignments only, unless based on autopsy findings. The present paper bears on the remedy for a second im- portant source of error which is largely within the scope and control of statisticians. Fortunately, this remedy can be ap- plied at once and surprisingly large corrections in the death rate for certain causes can be made available. The method of procedure consists in attempting to secure from physicians completer statements as to the cause of death, in those cases where the returns on the death certificate are given vaguely or indefinitely, or where there is evidence that the original state- ments do not tell the entire story. Thus physicians often report conditions like "acute nephritis" as the cause of death, and do not refer at all to the primary condition, such as "scarlet fever," "influenza," or "alcoholism," which was present and known to them. Again, "peritonitis" is frequently reported without reference to the "appendicitis" or to the "puerperal septicemia" which may have preceded it. The various forms of death by violence are still reported vaguely, and without due regard for the statistical requirements of assignment to the International List of Causes of Death. Certificates frequently do not permit one to determine whether death was due to accident, suicide, or homicide, and what was the means and character of the injury. This report is not the announcement of a discovery in the field of statistics. It is simply an attempt to put on record 49] Statistics of Causes of Death. 177 the results of a method followed for four years in the Statistical Bureau of the Metropolitan Life Insurance Company, in the treatment of the industrial mortality experience of that com- pany. We have realized that, if our material on the mortality of the American working classes is to be utilized to the full, every effort must be made to improve the quality of the basic data, especially since for many diseases and conditions the death rate is decidedly modified by the extent to which the query system is applied. The method is essentially that fol- lowed by the Registrar-General of England and Wales, and by the Division of Vital Statistics in the United States Census Bureau. We desire at this point to acknowledge our in- debtedness to Mr. George H. Van Buren, Chief of that Divi- sion, who aided materially in the introduction of the method into our office. Both the English* and the American f bureaus have already, in their annuals and in other publications, called attention to the changes resulting from their systems of in- quiry. A preliminary statement of the results obtained by our office appeared in the December, 1913, issue of this Quar- terly.! In the present paper we shall discuss the effects upon our returns on the basis of the much more extensive data now available. It is our hope that this complete statement will encourage other workers to similar efforts, and that in this way the returns of health departments and insurance com- panies may become more accurate and comparable. The technical procedure is as follows: The death certificates attached to the claim papers are carefully examined, and the staff engaged in this work determine whether the statement of cause of death given by the physician is satisfactory and complete for purposes of assignment. Statements of cause pre- senting no difficulty are at once classified according to the International List of Causes of Death. Joint causes are classi- fied according to the precedents and rules of the International Committee, as best exemplified by the methods of the United • Regiatrar-General of Births, Deaths and Marriages. Report, 1913, p. LXXIX. f Bureau of the Census. Mortality Statistics, 1911, p. 36. Bureau of the Census. Mortality Statistics, 1912, p. 23. Van Buren, Geo. H.: Mortality Statistics and the Physician, Amer. Jour. Pub. Health, Dec., 1915. Emerson, Haven, loc. cit. X Dublin, Louis I.; Kopf, Edwin W.: Experiment in the Compilation of Mortality Statistics, this Quar- terly, Dec, 1913. 178 American Statistical Association. [50 States Census Bureau. Wherever the statement of cause is considered unsatisfactory for classification, or where, from the statement presented to the Company by the claimant or from other available sources, there is an indication that a serious condition not mentioned on the certificates has con- tributed to the death, or where additional information is required before a satisfactory assignment can be made, a letter of inquiry, asking for the facts, is sent to the physician. Cleri- cal labor is minimized wherever possible through the use of form letters. A codified series of questions is employed, and the examiners indicate to the typists the question which is to be inserted in the form. The following is a copy of one of our series of letters sent to physicians : New York City Dear Doctor: This Company is analyzing its mortality experience for the year 191 , and in order that we may be able to classify accurately the death of who died on , and whose certificate you signed, we most respectfully ask you to send us the following information in addition to the statement now appearing on the death claim, viz.: Acute nephritis Additional data desired : Kindly indicate the primary cause of the ACUTE NEPHRITIS. Due to any contagious or infectious disease (scarlet fever, typhoid fever, etc.)? Directly due to alcoholism or exposure? Traumatic? If so, means of injury? The claim was duly paid by this Company under date of 191 , and this desired information will be used for statistical purposes only. We are confident that your interest in the advancement of the scientific study of Causes of Death will prompt you to comply with our request, and we beg you to accept our thanks. A stamped envelope is enclosed for your reply. Very respectfully yours, Statistician. (Please answer here) 15 At first we proceeded cautiously, inquiring only as to the means and character of the injury in cases of ill-defined violence. We also asked for the causes for the relief of which operations were performed (when expressions such as "operation," "sur- gical shock," or "laparotomy" were reported with no addi- tional data), the causes contributing to "peritonitis," and the 51] Statistics of Causes of Death. 179 more exact location of cancers and tumors. We asked for additional information when the terms were "dropsy," "heart failure," and others of like character included in the designa- tion "Ill-defined Diseases" in the International Classification. The scope of our questions has since been much extended. The following questions indicate the lines along which inquiry- is now made: Undesirable Returns and Character of Inquiry Made. Undesirable Returns. 1. "Injury," "Gunshot- Wound, " " Drowning, ' ' "Accidental death," or other ill-defined vio- lence. 2. "Operation," "Hysterec- tomy," "Laparatomy." 3. "Peritonitis." 4 "Acute nephritis. " 5. "Meningitis," or "Cere- brospinal meningitis." 6. "Apoplexy." 7. "Paralysis." 8. "General paralysis of the insane." 9. "Locomotor ataxia." Inquiry. Was death due to accident, suicide, or homicide? If accident, what kind of accident was the primary cause of death (steam railroad, street car, fall, etc.)? What was the cause, for the relief of which the operation was performed? Was the peritonitis secondary to typhoid fever? To tuberculosis? To puer- peral septicemia? To appendicitis? If postoperative, what was the primary cause? Was it accidental, suicidal, or homicidal? If so, what was the means of injury? What was the primary cause? Was it a contagious or infectious disease (scar- let fever, typhoid fever, etc.)? Was it directly due to alcoholism or ex- posure? Was it traumatic? If so, what was the means of injury? Was it epidemic? Tuberculous? Was it simple meningitis following lobar pneumonia, typhoid fever, or any other contagious or infectious disease? Was it traumatic? If so, what were the means and nature of the injury? Was it accidental, suicidal, or homicidal? Was this a case of cerebral hemorrhage? Was it superinduced by cerebral hemor- rhage? Was it a case of spinal paraly- sis? Of general paralysis of the insane? Was it due to syphilis? If so, was the presence of syphilis determined by history or tests? Was it of syphilitic origin? Traumatic? If so, what was the means of injury? 180 American Statistical Association. [52 10. "Progressive paralysis." 11. "Tumor." 12. "Cancer." 13. "Abscess." 14. "Burns." 15. Any terminal condition, origin not stated, such as "Septicemia," "Con- vulsions," or "Hemor- rhage." 16. "Acute cardiac dilata- tion," "Heart failure." 17. "Pneumonia." Was it due to a spinal lesion? Was it directly or remotely due to cerebral hemorrhage? Was it malignant? What was its loca- tion? What was its location? What was its location? What was its nature and cause? Was it tubercul- ous? Traumatic? Was death primarily due to burns re- ceived in burning building? (Such deaths are separately classified.) What was the primary cause? What was the primary cause? Was it lobar, bronchial, grippal, or tuber- culous? Was it traumatic? If so, was death due to accident, suicide, or homi- cide, and what was the means of injury? At the present time we are querying about 8.5 per cent, of the certificates of death received in our office. Satisfactory- replies are obtained from physicians in about three quarters of the cases; the proportion varies somewhat with the con- dition queried. Changes are made in the classification, as the result of inquiry, in about 70 per cent, of the replies re- ceived. It is a pleasure at this time to acknowledge our in- debtedness to the thousands of physicians whom we have ad- dressed, and who, without reimbursement, have put at our disposal their time and opinion in order to help in the campaign to improve vital statistics. It is an encouraging commentary on the scientific interest of the American practitioner that such a large return could be received. The following table shows the principal titles in which changes in assignment were made; it shows the number of deaths that would have been assigned to each title without inquiry, the number actually assigned after inquiry, and the ratio of the latter number to the former. The titles are arranged in the increasing order of these ratios. 53] Statistics of Causes of Death. 181 TABLE I. NUMBER OF DEATHS FROM CERTAIN CAUSES, BEFORE AND AFTER INQUIRY, AND PROPORTION OF LATTER TO FORMER, ARRANGED IN INCREASING ORDER OF PROPORTIONS. Metropolitan Life Insurance Company, Industrial Department; Mortality Experience, 1911-1914. Cause of Death. International List Number. Title. Deaths before Inquiry. Deaths after Inquiry. Deaths after Inquiry, per 100 Deaths before Inquiry. 185 117 066 061 046 062 186 067 119 020 094 045 092 081 120 028 009 156-163 029, 032-035 040 008 001 155 006 007 039 031 041 042 108 043 044 064 182 091 183-184 010 A63 030 051 056 172 037 038 A61 Fractures (causes not specified) Simple peritonitis — nonpuerperal Paralysis without specified cause Simple meningitis Other tumors (tumor3 of the female genital organs excepted) Locomotor ataxia Other external violence General paralysis of the insane Acute nephritis Purulent infection and septicemia Pulmonary congestion, pulmonary apoplexy . . . Cancer and other malignant tumors of other organs or of organs not specified Pneumonia (lobar and undefined) Diseases of the arteries, atheroma, aneurysm, etc Bright 's disease Tuberculosis of the lungs Diphtheria and croup Other suicides Other forms of tuberculosis Cancer and other malignant tumors of the stom- ach Whooping cough Typhoid fever Suicide by poison Measles Scarlet fever Cancer and other malignant tumors of the buc- cal cavity Abdominal tuberculosis Cancer and other malignant tumors of the peri- toneum, intestines, rectum Cancer and other malignant tumors of the fe- male genital organs Appendicitis and typhlitis Cancer and other malignant tumors of the breast Cancer and other malignant tumors of the skin Cerebral hemorrhage and apoplexy Homicide by firearms Bronchopneumonia Homicide by other means Influenza Other diseases of the spinal cord Tuberculous meningitis Exophthalmic goitre Alcoholism (acute or chronic) Traumatism by fall Syphilis Gonococcus infection Cerebrospinal fever 1,484 1,180 3,340 3,752 266 714 1,456 2,042 4,186 820 749 3,650 27,740 6,390 32,854 60,486 8,850 2,660 6,083 8,804 1,995 6,343 1,666 3,137 3,681 853 2,067 2,679 4,813 3,807 2,089 574 21,727 1,443 9,133 792 3,995 1,248 2,656 368 1.353 3,575 1,322 50 138 545 711 2,090 2,534 196 558 1,158 1,627 3,375 725 664 3,279 26,299 6,199 32,745 60,613 8,881 2,674 6,120 8,932 2,025 6,440 1,696 3,216 3,778 2,133 2,769 5,003 3,959 2,195 604 23,029 1,532 9,708 848 4,370 1,389 3,024 433 1,633 4,432 2,350 115 536 36.7 60.3 62.6 67.5 73.7 78.2 79.5 79.7 80.6 88.4 88.7 94.8 97.0 99.7 100.2 100.4 100.5 100.6 101.5 101.5 101.5 101.8 102.5 102.6 103.2 103.2 103.4 103.9 104.0 105.1 105.2 106.0 106.2 106.3 107.1 109.4 111.3 113.9 117.7 120.7 124.0 177.8 230.0 388.4 The indefinite title " fractures (cause not specified)" shows the greatest reduction in the number of assignments. The number of deaths after inquiry is only 36.7 per cent, of the 182 American Statistical Association. [54 number originally returned. In view of the fact that the number of persons exposed is constant, the decrease in the number of deaths is accompanied by a corresponding reduction in the death rate. We may, therefore, say that the final death rate for this cause was 63.3 per cent, less than the one which would originally have been quoted. Such general titles as "other external violence" and "cancer of organs not speci- fied" were in like manner greatly reduced through the deter- mination of the nature of the violence, or of the location of the cancer. Considerable reductions were obtained upon inquiry into the character of such returns as "paralysis" and "loco- motor ataxia"; for in such cases added information with ref- erence to blood tests, etc., gave sufficient data upon which more definite assignments could be made. On the other hand, a large number of causes, especially those referring to the in- fectious diseases, show very little change. Tuberculosis of the lungs, for example, shows an increase of but .2 per cent. The infectious diseases of children, such as "measles" and "scarlet fever," give somewhat greater percentages of in- crease, 2.5 and 2.6 respectively; these increases were made at the expense of terminal conditions, such as "hypostatic pneu- monia" and "acute nephritis," which are very often given as the causes of death. Cancers of definitely specified organs were considerably increased in the number of assignments, with a corresponding increase in the rates. Thus " cancer and other malignant tumors of the breast," of which there are many cases, showed an increase of 5.1 per cent, in the death rate. Such socially significant titles as "alcoholism," "syphilis," and "gonococcus infection" gave very marked rates of in- crease, 20.7, 77.8, and 130.0 per cent., respectively. That we could add two thirds as many deaths as were originally assigned to "syphilis" is in itself sufficient justification for the effort involved by our method. The greatest percentage of increase is shown by the title "cerebrospinal fever," which was increased from 138 to 536 deaths, or nearly fourfold. The more definite titles to which some of the undesirable titles were changed are shown in the following table: 55] Statistics of Causes of Death. 183 TABLE II. ILL-DEFINED CAUSES OF DEATH, AND DEFINITE TITLES TO WHICH RE-ASSIGNED, BY NUMBER AND PERCENTAGE OF CHANGE IN CLASSIFICATION. Metropolitan Life Insurance Company, Industrial Department; Mortality Experience, 1911-1914. Ill-Defined Term as Classified before Inquiry. Title Assigned after Inquiry. Number and Per- centage of Changes in Classification. ■\T„ m : Percentage ber - ' Replies. Purulent infection and septicemia (Total replies, 184.) Cancer and other malig- nant tumors of other organs or of organs not specified (Total replies, 572.) Meningitis (Total replies, 1,653.) Locomotor ataxia (Total replies, 321.) Paralysis without speci- fied cause (Total replies, 1,449.) General paralysis of the insane (Total replies, 956.) Organic diseases of the heart* (Total replies, 714.) Diseases of the arteries, atheroma, aneurysm, (Total replies, 603.) Pneumonia! (Total replies, 3,005.) Total changes from "Purulent infection and septi- cemia" not speci- I "Other diseases of the uterus" Puerperal septicemia Acute abscess Other titles Total changes from " Cancer . fied" Cancer and other malignant tumors of the buccal cavity Cancer and other malignant tumors of the stomach. . Cancer and other malignant tumors of the peritoneum Cancer and other malignant tumors of the female gen- ital organs Cancer and other malignant tumors of the breast. . . . Cancer and other malignant tumors of the skin Other titles Total changes from "Meningitis" I Tuberculous meningitis Cerebrospinal fever Pneumonia Diarrhea and enteritis — 2 years and over Other titles Total changes from "Locomotor ataxia" f Syphilis \ Other titles Total changes from "Paralysis without specified I "Other diseases of the spinal cord" Cerebral hemorrhage, apoplexy General paralysis of the insane Other titles Total changes from "General paralysis of the in sane" J Syphilis \ Other titles Total changes from "Organic diseases of the heart" i Cerebral hemorrhage, apoplexy I Pneumonia J Other titles Total changes from "Diseases of arteries, etc." . (Syphilis Cerebral hemorrhage, apoplexy Other titles Total changes from "Pneumonia" I Influenza Bronchopneumonia Lobar pneumonia Other titles 134 6 54 8 66 423 25 75 61 148 83 28 3 1,234 294 363 79 62 436 163 148 15 1,259 175 119 531 491 40 264 46 72 146 317 65 166 86 1,754 22S 586 577 363 72.8 3.3 29.3 4.3 35.9 74.0 4.4 13.1 10.7 25.9 14.5 4.9 .5 74.7 17.8 22.0 4.8 3.8 26.4 50.8 46.1 4.7 86.9 12.1 61.1 5.5 8.2 55.5 51.4 4.2 37.0 6.4 10.1 20.4 52.6 10.8 27.5 14.3 58.4 7.6 19.5 19.2 12.1 * Most of the terms included under the title "organic diseases of the heart are fairly definite. How- ever certain expressions like "acute cardiac dilatation" and "cardiac insufficiency are often reported when they are only terminal symptoms of other diseases. It is these expressions that are covered by our inquiry. . .... . . . •(■Assignments to "lobar pneumonia" should be regarded as confirmations of original assignments to "pneumonia," rather than as changes. 184 American Statistical Association. TABLE II— Continued. [56 Ill-Defined Term as Classified before Inquiry. Title Assigned after Inquiry. Number and Per- centage of Changes in Classification. Num- ber. Percentage of Total Replies. Pulmonary congestion, pulmonary apoplexy (Total replies, 155.) Peritonitis — non-puer- peral (Total replies, 575.) Acute nephritis (Total replies, 1,935.) Other diseases of the uterus (Total replies, 173.) Traumatism by firearms (Total replies, 119.) Fractures (cause not specified) (Total replies, 1,045.) Other external violence (Total replies, 504.) Ill-defined diseases (Total replies, 442.) Total changes from "pulmonary apoplexy" Organic diseases of the heart Chronic bronchitis Pneumonia Bright's disease Other titles Total changes from "Peritonitis" Abdominal tuberculosis Diarrhea and enteritis — 2 years and over Appendicitis and typhlitis Salpingitis and other diseases of the female genital organs Puerperal septicemia Other titles Total changes from "Acute nephritis" Scarlet fever Influenza Alcoholism (acute or chronic) Bright's disease Other titles Total changes from "Other diseases of the uterus" Gonococcus infection Cancer and other malignant tumors of the female gen- ital organs Uterine tumor (noncancerous) Cysts and other tumors of the ovary Salpingitis and other diseases of the female genital organs Puerperal septicemia . Other titles Total changes from traumatism by firearms (Suicide by firearms Homicide by firearms Othertitles Total changes from " Fractures (cause not fied)." Traumatism by fall Traumatism by crushing — electric railway Traumatism by crushing — steam railway Traumatism by crushing — automobiles Traumatism by crushing — other vehicles Traumatism by other means . Other titles Total changes from "Other external violence' Purulent infection and septicemia Traumatism by fall Traumatism by machines Traumatism by crushing — steam railway Traumatism by crushing — electric railway Traumatism by crushing — automobiles Traumatism by crushing — other vehicles . Other titles Total changes from "Ill-defined diseases" . . . Malaria Tuberculosis of the lungs Organic diseases of the heart , Bright's disease Other titles speci- 99 15 6 8 8 62 476 44 20 105 45 86 176 839 213 74 409 119 15 7 13 21 35 22 95 6 87 2 949 646 33 25 27 51 57 110 400 15 161 23 29 16 17 37 102 822 15 IS 83 21 185 63.9 9.7 3.9 5.2 5.2 40.0 82.8 7.7 3.5 18.3 7.8 15.0 30.6 43.4 3.5 3.9 11.0 3.8 21 1 68.8 8.7 4.0 7.5 3.5 12.1 20.2 12.7 79.8 5.0 73.1 1.7 90.8 61.8 3.2 2.4 2.6 4.9 5.5 10.5 79 4 3.0 31.9 4.6 5.8 3.2 3.4 7.3 20.2 72 9 3.4 4.1 18.8 4.8 41.9 57] Statistics of Causes of Death. 185 Letters were received from physicians in connection with 1,653 cases originally diagnosed as "meningitis." In 1,234 of these cases, or 74.7 per cent., the classification was changed to other and more definite titles. "Cerebrospinal fever" received 22 per cent, of the original "meningitis" returns; "tuberculous meningitis," 17.8 per cent.; and "pneumonia (lobar and undefined)," 4.8 per cent. The title "paralysis without specified cause" was the subject of 1,449 replies; the classification was changed in 1,259 instances, or 86.9 per cent. The larger proportion (61.1 per cent.) of these "paralysis without specified cause" cases were classified under "cerebral hemorrhage and apoplexy." "Peritonitis" was changed in classification in 476 out of 575 cases, or 82.8 per cent. These changes were credited chiefly to the titles "appendicitis and typhlitis," "puerperal septicemia," "salpingitis," and other diseases of the female genital organs. Ill-defined returns of "traumatism by firearms" were •changed in 79.8 per cent, of the cases queried. The greater part (73.1 per cent.) of these deaths was assigned to the title "homi- cide by firearms." "Fractures (cause not specified) " were a fruitful source of additions to the class of "traumatism by fall"; 646 ill-defined fractures (61.8 per cent.) were so assigned. After this examination of the ill-defined terms and the more definite titles to which they were assigned, we may proceed naturally to the other aspect of the change; namely, to de- termine how the mortality is constituted in those causes which show an increase in the number of deaths. This is indicated by Table III. 186 American Statistical Association. [58 TABLE III. ADDITIONS TO CERTAIN CAUSES OF DEATH FROM INDEFINITE TITLES, NUMBER AND PERCENTAGE CHANGED FROM EACH INDEFINITE TITLE. Metropolitan Life Insurance Company, Industrial Department; Mortality Experience, 1911-1914. Cause of Death Title Receiving Additions. Title before Inquiry. Additions. Number. Per Cent. Typhoid fever Measles Scarlet fever Whooping cough Diphtheria and croup Influenza Tuberculosis of the lungs Tuberculous meningitis Total changes to " typhoid fever" Simple meningitis Organic diseases of the heart Pneumonia . Other diseases of the intestines . Simple peritonitis . Acute nephritis. Bright's disease. Cause of death not specified or ill-defined. Other titles. Total changes to "measles". (Whooping cough. . Simple meningitis. Bronchopneumonia . ■ Pneumonia. Acute nephritis. . ._ I Other titles ! Total changes to "scarlet fever". . . (Simple meningitis Bronchopneumonia Pneumonia ■ Acute nephritis Bright's disease (Other titles Total changes to "whooping cough' ' Simple meningitis Convulsions of infants Bronchopneumonia Pneumonia. Pulmonary congestion, pulmonary apoplexy. Acute nephritis. Other titles. Total changes to "diphtheria and croup' Acute endocarditis . Organic diseases of the heart . Diseases of the larynx. Acute bronchitis. Bronchopneumonia . Pneumonia. Diseases of the pharynx Acute nephritis Other titles Total changes to "influenza" (Simple meningitis Pneumonia , Acute nephritis ( Other titles Total changes to "tuberculosis of the lungs' ' Simple meningitis Organic diseases of the heart Chronic bronchitis Pneumonia Cause of death not specified or ill-defined. . . . Other titles Total changes to "tuberculous meningitis". j Meningitis \ Other titles 101 100 29 28.7 3 3.0 5 5.0 6 5.9 16 15.8 21 20.8 3 3.0 3 3.0 15 14.9 89 100.0 3 3.4 19 21.3 9 10.1 31 34.8 13 14.6 14 15.7 98 100 7 7.1 4 4.1 3 3.1 68 69.4 5 5.1 11 11.2 45 100.0 12 26.7 2 4.4 6 13.3 14 31.1 2 4.4 5 11.1 4 8.9 35 100.0 2 5.7 2 5.7 6 17.1 2 5.7 4 11.4 3 8.6 2 5.7 10 28.6 4 11.4 394 100.0 40 10.2 228 57.9 75 19.0 51 12.9 166 100.0 6 3.6 6 3.6 6 3.6 70 42.2 16 9.6 62 37.3 377 100.0 294 78.0 83 22.0 ■59] Statistics of Causes of Death. TABLE III— Continued. 187 Cause of Death Title Receiving Additions. Title before Inquiry. Additions. Number. Per Cent. Syphilis Cancer and other malig- nant tumors of the stomach and liver Cancer and other malig- nant tumors of the fe- male genital organs •Cancer and other malig- nant tumors of the breast Alcoholism Cerebrospinal fever Cerebral hemorrhage, apoplexy Organic diseases of the heart* Total changes to " syphilis " Locomotor ataxia Other diseases of the spinal cord Cerebral hemorrhage, apoplexy Paralysis without specified cause General paralysis of the insane _. Diseases of the nervous system other than those speci- fied Diseases of the arteries, atheroma and aneurysm Other titles Total changes to "cancer and other malignant tumors of the stomach and liver" Cancer and other malignant tumors of other organs or of organs not specified Other tumors (tumors of the female genital organs excepted) Diseases of the esophagus. . . Other diseases of the stomach Other diseases of the liver. . . , Other titles Total changes to " cancer and other malignant tumors of the female genital organs" Cancer and other malignant tumors of other organs or of organs not specified Other tumors (tumors of the female genital organs excepted) Uterine tumor (noncancerous) Other diseases of the uterus . . . Other titles Total changes to "cancer and other malignant tumors of the breast" I Cancer and other malignant tumors of other organs or of organs not specified Nonpuerperal diseases of the breast (cancer excepted) Other titles Total changes to "alcoholism" I Simple meningitis Acute nephritis Cause of death not specified or ill-defined Other titles Total changes to "cerebrospinal fever" I Simple meningitis \ Other titles Total changes to "cerebral hemorrhage, apoplexy I Paralysis without specified cause Organic diseases of the heart Diseases of the arteries, atheroma, aneurysm Bright's disease Other titles Total changes to "organic diseases of the heart". Cerebral hemorrhage, apoplexy Paralysis without specified cause Acute endocarditis Diseases of the arteries, atheroma, aneurysm Pneumonia Pulmonary congestion, pulmonary apoplexy Acute nephritis Bright's disease Senility Fractures (cause not specified) Ill-defined organic disease. . . . Cause of death not specified or ill-defined . Other titles 1,031 148 59 34 34 491 65 104 130 7 7 7 21 106 83 9 14 289 14 213 10 52 401 363 38 1,408 885 46 166 137 174 287 10 13 10 14 12 15 25 9 13 11 39 43 73 100.0 14.4 5.7 3.3 3.3 47.6 9.3 6.3 10.1 57.7 7 5.4 4 3.1 7 5.4 13 10.0 24 18.5 100.0 77.9 3.7 3.7 3.7 11.1 100.0 78.3 8.5 13.2 100.0 4.8 73.7 3.5 18.0 100.0 90.5 9.5 100.0 62.9 3.3 11.8 9.7 12.4 ♦See footnote on this title in Table II. 188 American Statistical Association. TABLE III— Continued. [60 Cause of Death Title Receiving Additions. Title before Inquiry. Additions. Number. Per Cent. Diseases of the arteries, atheroma, aneurysm Bronchopneumonia Pneumonia (lobar and undefined) Appendicitis and typh- litis Bright's disease Puerperal state — total Puerperal septicemia Puerperal albuminuria and convulsions Total changes to "diseases of the arteries, atheroma, aneurysm" Other diseases of the spinal cord Softening of the brain Paralysis without specified cause Organic diseases of the heart Pneumonia Pulmonary congestion, pulmonary apoplexy Acute nephritis Gangrene Senility _ _ Cause of death not specified or ill-defined Other titles Total changes to "bronchopneumonia" Simple meningitis Pneumonia Other titles Total changes to "pneumonia" Simple meningitis Organic diseases of the heart Pleurisy Simple peritonitis (nonpuerperal) Cerebral hemorrhage, apoplexy Bright's disease Other titles Total changes to "appendicitis and typhlitis" f Intestinal obstruction j Simple peritonitis (nonpuerperal) [ Other titles Total changes to "Bright's disease" Cerebral hemorrhage, apoplexy Organic diseases of the heart Diseases of the arteries, atheroma, aneurysm Pulmonary congestion, pulmonary apoplexy Acute nephritis Other diseases of the kidneys and annexa Senility Fractures (cause not specified) Ill-defined organic disease Other titles Total changes to " puerperal state — total " Purulent infection and septicemia Convulsions (nonpuerperal) Pneumonia Simple peritonitis (nonpuerperal) Acute nephritis Bright's disease Uterine hemorrhage (nonpuerperal) Other diseases of the uterus Other titles Total changes to " puerperal septicemia " I Purulent infection and septicemia Simple peritonitis Diseases of the uterus Other titles Total changes to "puerperal albuminuria and con- vulsions" I Convulsions (nonpuerperal) Acute nephritis Bright's disease Other titles 126 100.0 5 4.0 9 7.1 9 7.1 6 4.8 5 4.0 4 3.2 10 7.9 28 22.2 10 7.9 4 3.2 36 28.6 660 100.0 32 4.8 586 88.8 42 6.4 329 100.0 79 24.0 72 21.9 13 4.0 10 3.0 10 3.0 44 13.4 101 30.7 156 100.0 6 3.8 105 67.3 45 28.8 235 100 7 3.0 19 8.1 13 5.5 8 3.4 74 31.5 12 5.1 7 3.0 9 3.8 16 6.8 70 29.8 368 100.0 54 14.7 32 8.7 15 4.1 87 23.6 58 15.8 26 7.1 4 1.1 40 10.9 52 14.1 189 100 50 26.5 77 40.7 32 16.9 30 15.9 125 100 32 25.6 54 43.2 26 20.8 13 10.4 61] Statistics of Causes of Death. TABLE III— Concluded. 189 Cause of Death Title Receiving Additions. Title before Inquiry. Additions. Number. Per Cent. Total changes to "suicide" 46 24 10 6 2 4 945 43 646 161 95 14S 7 87 15 16 23 100 Acute poisonings 52 2 Suicide Absorption of deleterious gases (conflagration excepted) Traumatism by firearms. . . . 21.7 13.0 Fractures (cause not specified) 4.3 Other titles 8.7 Total changes to "traumatism by falling". . . . Simple meningitis 100.0 4.6 Traumatism by falling ■ Fractures (cause not specified) 68.4 Other external violence 17.0 Other titles 10.1 Total changes to "homicide" 100.0 Simple peritonitis (nonpuerperal) . . . 4.7 Traumatism by firearms 58.8 Homicide — total Fractures (cause not specified) . . . 10.1 Other external violence 10.8 Other titles 15.5 Of the 101 cases added to typhoid fever, 28.7 per cent, were originally classified as "simple meningitis," 20.8 per cent, as "acute nephritis," and 15.8 per cent, as "simple peritoni- tis." There were 89 additions to "measles," 98 to "scarlet fever," 45 to "whooping cough," and 35 to "diphtheria and croup," making an addition of 267 deaths to these four dis- eases of childhood. "Acute nephritis" played an important part in the original assignment in all of these four diseases, but more especially in "scarlet fever," where 68 deaths, or 69.4 per cent, of the changes, were originally so classified. In like manner, "bronchopneumonia" and "pneumonia" (un- specified), were the original assignments in many of these con- ditions; this applies particularly to "measles" and "whooping cough." Except for "diphtheria," the indefinite title "sim- ple meningitis" is a convenient cloak for the acute infections of childhood. "Influenza" and" tuberculosis of the lungs" both received significant additions from the title "pneumonia," the former receiving 228 additional deaths and the latter 70. Of the total changes to tuberculous meningitis, 294, or 78.0 per cent., were originally classified as meningitis. An analysis of the sources of the additions to syphilis is interesting. Of the 1,031 changes to this title, 148 were from locomotor ataxia, 491 from general paralysis of the insane, and 104 from a large number of conditions, connected for the 190 American Statistical Association. [62 most part with spinal lesions. Our inquiries with reference to "general paralysis of the insane" have definitely confirmed the virtually unanimous opinion of clinicians that this condi- tion is syphilitic in origin. So uniform is our finding, that we are considering seriously the advisability of discontinuing our inquiries into this condition, and assuming the existence of syphilis in such cases. As might be expected, the additions to "cancers of specified organs" are at the expense of the residual title, "cancers of organs not specified." The importance of this change is obvious in view of the increasing interest in the location of the malignant growths. The number of deaths from "acute and chronic alcoholism" was increased at the expense of "acute nephritis"; 213 out of 289 deaths, or 73.7 per cent., were so added. It will be unnecessary to go further into this analysis, since the various parts of the table speak for themselves. The foregoing tables and text are sufficient to indicate the possibilities inherent in the intensive questioning of mortality returns. It does not lie within the power of the statistician to correct errors which depend upon the diagnostic ability of physicians, or upon circumstances which do not permit ade- quate opportunity for case observation or for accurate clinical or pathological findings. There is, however, a class of errors which he can undoubtedly reduce to a minimum. He can raise the standard of accuracy in mortality statistics by in- viting the physician to give information such as he is able and willing to impart. It is reasonable to assume that the physi- cian will, at first, have in mind not so much the statistical use of the information which he possesses as the immediate and uppermost clinical phase of the case. His efforts in the last stage of a losing battle against disease or injury are so often de- voted to combating serious complications, that he is more than likely k) certify only the immediate and not the primary cause of death. The statistician can tactfully point out to him an error of omission. Experience has demonstrated that, in a large proportion of cases, physicians manifest sufficient interest in the precision of our vital statistics to supply the additional and qualifying statements. As inquiries are made, moreover, physicians become more and more aware of the requirements 63] Statistics of Causes of Death. 191 of statistical technique in making assignments. An analysis of our returns shows an increasing proportion of satisfactory statements for certain causes of death. A physician to whom an inquiry is once sent will usually not make the same in- definite statement in his subsequent certificates of death. This means for advancing the accuracy of cause of death statistics is at hand in every registration and compiling office, and it is hoped that it will soon be adopted by vital statisti- cians generally. The fruitful character of the returns, af- fecting as they do the basic material of vital statistics, the simplicity of the method, and its low cost both in time and in money, indicate plainly the desirability at the present time of inquiries to physicians as an integral part of the classifica- tion of causes of death. Certainly the day has arrived when material cannot be admitted into the realm of good vital statis- tics unless it has previously been subjected to careful inquiry such as we have outlined above. That is the least which can be expected, in view of the uncertainty of much of the material, due in the first instance to errors of bedside diagnosis uncor- rected by autopsy. I II ii ill mi i ii i ii linn 013 738 802 9 « Hollinge pH LIBRARY OF CONGRESS win mi inn ii inn mi 013 738 802 9 « Hollinger Corp. P H8.5