We are an overnourished nation and we should wake up and regard excessive food intake just as serious as it is an intoxication with a slow and insidious harmful effect, not so acute or dramatic as intoxication by alcohol or drugs, but almost as serious. The middle aged husband today, having been brought up to eat (to clean up) too much of everything on his plate naturally finds it difficult to understand why he shouldn't continue to eat too much, and he is quite likely to resent the advice of his doctor and particularly of his wife who has an especially hard time of it. His habit is already fixed-it is difficult to teach an old dog new tricks. Thus we must get this education over to pediatricians, parents, school teachers, and public health personnel who deal with children.

(c) For optimal function of an alert brain a really good blood supply is needed, and this means not only avoidance of overnutrition but also physical fitness in the way of firm and active muscles. It is said now that if you want to know how flabby your brain is, feel your leg muscles. Regular exercise of the large muscles of the body is essential to positive health-a walk of 4 miles, or a comparable activity, a day, is, I believe, the minimum needed for good health-or 28 miles a week. You may prefer to swim or to play golf without a cart, or to bicycle, it doesn't matter which. Physiological and psychological benefits are great; bloodclot prevention, and the delaying of serious arteriosclerosis affecting heart, brain, and kidneys are clear results of this essential health habit which needs to be emphasized far and wide in this era of our slavery to machines of all kinds. During active use of the legs, their muscles carry out 30 per cent of the circulation of the blood relieving the heart of that extra load.

(d) The avoidance of smoking and of the use of other tonic substances such as opiates and L.S.D. and also of excessive alcohol are all quite clearly to be included in our list of proper health habits, and now even coffee and tea in too large amounts daily can cause stress and this can have harmful results.

(e) Excessive stress is to be avoided but minor stresses are a part of life and are to be met by antidotes like fatiguing exercise and tranquilizing programs of one sort or another in art, in music, in literature, and even in one's work.

All these desirable health habits are often difficult to start in later life but they are easily inculcated in the young if we go about it wisely, by example as well as by precept. And of course there are rules also for the prevention of infections and accidents and for early detection of cancer.

I shall be glad to try to answer questions.

Senator NEUBERGER. The next witnesses are Dr. Ralph Thiers, Dr. Slack, and Dr. Caceres, if they will come forward.

STATEMENTS OF RALPH E. THIERS, PH. D., PROFESSOR OF BIOCHEMISTRY AND DIRECTOR OF CLINICAL CHEMISTRY LABORATORIES, DUKE UNIVERSITY MEDICAL CENTER; WARNER V. SLACK, M.D., ASSISTANT PROFESSOR, MEDICINE AND COMPUTER SCIENCES, UNIVERSITY OF WISCONSIN SCHOOL OF MEDICINE; AND CESAR A. CACERES, M.D., INSTRUMENTATION ACTIVITIES CHIEF, HEART DISEASE CONTROL BRANCH, DIVISION OF CHRONIC DISEASES, BUREAU OF STATE SERVICES, PUBLIC HEALTH SERVICE, AND ASSOCIATE PROFESSOR OF MEDICINE, GEORGE WASHINGTON UNIVERSITY

Dr. THIERS. Senator Neuberger, Dr. Slack is on your right, Dr. Caceres is next, and I am Dr. Thiers.

Senator NEUBERGER. Dr. Thiers, I believe you are professor of biochemistry at Duke University Medical Center in North Carolina. Dr. THIERS. Yes.

Senator NEUBERGER. And Dr. Slack, will you identify yourself? Dr. SLACK. I am assistant professor of medicine and computer sciences at the University of Wisconsin.

Senator NEUBERGER. Ånd Dr. Caceres.

Dr. CACERES. Chief of the Instrumentation Activities Field Station, Heart Disease Control Branch, Division of Chronic Diseases, U.S. Public Health Service, and associate professor of medicine, George Washington University.

Senator NEUBERGER. We welcome the three of you and look forward to hearing your statements. How are you going to present this? Individually?

Dr. THIERS. Senator Neuberger, I have been asked to say a few words in an introductory fashion.

In order to set a background for the following testimony-when one goes to see a physician with a problem, an orderly sequence of events takes place, which has been written on this flip chart. This is a systematic procedure which is taught to physicians at medical schools.

First, the patient makes his complaint, for example: "Doctor, I have a pain."

The doctor then takes a history of the patient. He then does a physical examination, using his five senses to examine the patient. Then he comes to a tentative diagnosis. On the basis of this tentative diagnosis, he orders certain laboratory examinations to be performed on the patient. For example, "We will get a blood sample, Mr. Smith, for this, that, and the other thing. We will ask you to take an ECG, a spirogram, et cetera.”

When he gets the results back from these examinations, he makes his diagnosis. On the basis of that diagnosis he begins treatment of the patient; "Mr. Smith, we are going to have to ask you to do this, that, and et cetera. Treatment is, of course, the goal of the whole

process.

First, Dr. Slack is going to talk on one aspect of historytaking, which he has placed on computer. Next, Dr. Caceres is going to talk about two aspects of laboratory examination, the ECG and the spirogram. And then I am going to talk about analytical considerations in general, with respect to laboratory examinations, using clinical chemistry as a specific example.

(A description of the instruments to be demonstrated follows:)

The Linc (laboratory instrument computer: A small, versatile digital computer which has been programmed at the University of Wisconsin Medical Center to collect the information of clinical histories directly from patients. Questions are presented to patients on a cathode-ray screen and responses are made by keyboard entries. Question presentation is varied in accordance with patients' responses-for example, a "yes" response to a general question is followed by a series of specific qualifying questions and a "don't understand" response is followed by explanatory statements. All responses are stored on magnetic tape for use in patient care and clinical research. Upon completion of the medical interview, a summary is printed by teletype for immediate clinical use. The computer-based medical history system will be demonstrated using an allergy history program for example.

Electrocardiogram on line with computer: The electrocardiogram is recorded on a data acquisition chart consisting of a standard electrocardiograph, a magnetic tape record, and a digital coder. The tape recorder records the electrical signal for playback into the computer, and the coder is used to make identification of the signal, by the computer, possible. The data acquisition chart is manufactured by Computer Instruments Corp., Hempstead, N.Y. The signal is transmitted over standard telephone lines using a DATA-phone set provided by the American Telephone & Telegraph Co.

The computer used (Control Data 160-A) is at the Instrumentation Field Station (IFS) of the U.S. Public Health Service. It is capable of performing 80,000 69-803 0-66

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additions in a second-roughly equivalent to adding all the entries on 200 pages from a telephone direction. The electrocardiogram report is transmitted back to the sender using the conventional teletypewriter.

Spirometer on line with computer: A wedge spirometer and an amplifier manu. factured by Med-Science Electronics, Inc., St. Louis, to test a subject for lung function, vital capacity and obstructive lung disease. The analysis, return, and printout of the spirogram is available almost instantaneously. The electrical signal from the spirometer is played into the data acquisition unit and transmitted to the computer and returned by the teletypewriter in a manner similar to that for the electrocardiogram.

Technicon SMA 12 autoanalyzer (blood chemistry): Multiple analysis—a dozen simultaneous tests from a thimbleful of serum-is possible on this instrument. Samples and standards are analyzed by the machine at the rate of 30 per hour and its 12 findings for each sample are recorded sequentially on a single, calibrated piece of paper. The 12 tests are for uric acid, inorganic phosphate, cholesterol, lactic dehydrogenase, total protein, albumin, urea, glucose, calcium, bilbirubin, alkaline phosphatase, and glumatic oxalectic transaminase. Its manufacturers say that the SMA (sequential multiple analyzer) 12 can perform 1,200 blood tests per 8-hour day, requiring the full-time attention of only one technician. The SMA 12 weighs 900 pounds.

Warner-Chilcott robot chemist: An analytical instrument designed to duplicate automatically, but with greater precision, the manual steps performed in chemical assays such as blood constitutent analyses. The robot is capable of automatically performing as many as 120 tests per hour using the principle of discreet sampling. The digital presentation of the results of each analysis can be easily fed into data processing equipment.

The unit consists of

1. A programmer which controls all working elements by means of an electrical command and response system.

2. A presentation module from which prepared samples to be analyzed are drawn automatically.

3. A pipetter and reagent dispenser which delivers predetermined quantities of samples and reagents to individual process tubes.

4. A processing turntable with thermostatic temperature control which, through rotation, permits performance of all operations sequentially.

5. A spectrophotometer which reads the optical density of each sample by means of photoelectric cells, converts the result to digital form and displays it while relaying it to the data converter or printer (analog to digital converter).

6. The data converter prints the information, with a sample identification number, on a paper tape.

Dr. SLACK. Thank you, Dr. Thiers.

The medical history is that portion of the clinical transaction in which the doctor interviews the patient. There are many questions which in the good medical situation should be asked of all patients at regular intervals, and many physicians consider the medical history to actually be the most important aspect of the clinical process. But in spite of this, there has been relatively little research done on the medical history, and doctors and patients have not been helped much with the problems of medical interviewing.

And there are significant problems with regard to the medical history as it is traditionally taken.

In the first place, it is very time consuming. Medical history is a very time-consuming process, and incomplete or inadequate histories are often the result of time limitations beyond the physician's control. And as a corollary to this, the medical history process in very expensive. Actually, talk is one of the most expensive commodities in clini

cal medicine.

Furthermore, the use of the data collected from the medical history is rendered very difficult by the methods used to record these data.

First of all, the traditional illegibility of the physician's handwriting is a major problem, and furthermore the lack of standardization of

these records makes retrieval of this information for patient care and clinical research difficult and often impossible.

Now, at the University of Wisconsin Medical Center, using a small digital computer, we have attempted on a research basis to try to overcome some of these problems.

Basically, what we are doing is programing a digital computer as a model of the physician as an interviewer, to take medical history information directly from patients.

We have here an example of the computer in use at the University of Wisconsin. The patient sits in front of the computer and the questions are presented to the patient on the cathode ray screen, which is very much like a television screen. The patient responds by pushing keys on the keyboard in front of the computer. And, basically, this is a conversation between the computer and the patient.

Now, the display on the screen now says: "Before proceeding I need to have your name. Please type this and then press the "Go" bar. The patient proceeds to type her name into the machine. These responses are going directly into the computer memory and being stored on magnetic tape, thus eliminating the need for punchcards or light-sense or mark-sense or other intermediary data handling.

Now Mrs. Rupp is entering today's date, and the computer has already taken her age, and she proceeds to type in the hospital number, presses the "Go" bar and the computer says, "Now if you will press 'Go' we will begin with the medical questions.

This demonstration is one of questions dealing with symptoms of allergies. But at the University of Wisconsin we are extending this project and hope eventually to have the complete medical history in computer-based form. The demonstration this morning will be of symptoms of allergy.

The computer says, "Do you know what chest wheezes are?" If the patient says, "I don't understand," and presses button 4, then the "Go" bar, the computer explains "Wheezes are squeaking sounds in the chest, with breathing. Do you know what I mean?"

If she still doesn't understand, we reword the question and say, "Have you had whistling or squeaking sounds with breathing?" If she still doesn't understand and presses 4 it says, "I don't mean gurgling or other noises in your throat or mouth. Have you ever had wheezing in your chest on breathing?" And if she still doesn't understand, it leaves "wheezing" but the fact that the concept of wheezing was not understood is recorded and printed out for the physician's use.

And now we are on to the hay fever syndrome. And the computer asks, "Have you ever suffered from running or stuffy nose with sneezing and watery, itching eyes?" If she says, "No," to this, pressing button 2, the concept of hay fever is left then.

Excuse me. We don't quite trust her response to this, and the computer asks, "Have you ever suffered from hay fever or allergic nose trouble?" When she says "No" to this, the computer moves on to hives, first of all giving her some words of encouragement, saying, "You have done very well, and you don't have many more questions to answer. Press go to continue."

Now with regard to hives, the computer explains that hives are white blotches on the skin which occur suddenly and usually itch. "Have you ever had hives?" If she says "No," the computer skips the

subject of hives and says, "There aren't many more questions. Shall we continue?"

She says "Yes." We proceed to the problem of drug allergies. "Have you ever received penicillin?" If the answer is "Yes," pressing button 1, the computer says, "Have you ever suffered from chest wheezing, skin rash, swollen face, and a number of symptoms that can result from allergic reaction to penicillin?" If the patient says "Yes," the computer branches out and asks specifically about these symptoms. "Did you have skin rash?" We will say "Yes."

"Did you have joint pains?" We will say "Yes." "Did you have chest wheezing or shortness of breath after taking penicillin?" We will say "No."

"Did you have swollen lymph glands after taking penicillin?" "Yes." "Did you have fever after taking penicillin?" We will say "No."

And "Did you have swelling of your face after taking penicillin?" We can say "Yes."

Then it asks, "Have you had more than one penicillin reaction?" We will say, "No." And then it branches and asks the patient now to type in the year about when you had your penicillin reaction: "1965." And then pressing "Go," we branch "Have you had a reaction after penicillin injection?" We will say "Yes."

It may be important to differentiate between the allergic reactions to an injection of penicillin or an allergic reaction to the taking of tablets orally.

"Did you have a reaction after taking penicillin tablets?" We will say "No."

"Did your penicillin reaction ever last more than a day?" We will say "No."

"Type in the number of hours of your longest or only penicillin reaction." We might say "10 hours," or whatever, "5 hours." And then "Go."

Now we are on to another drug, which can be an important cause of allergic problems-aspirin. "Have you ever taken aspirin?" We say "Yes." The computer again asks, "Well, have you had any of these symptoms: skin rash, swollen joints," and so forth with aspirin? We say "No." The computer, not quite satisfied with that response, asks, "Have you ever had any bad reaction after taking aspirin?" The patient says "No." The computer says, "Good. Shall we continue?" "Yes, continue."'

"Have you ever received tetanus or rabies shots?" If the patient says "No," this is an important point, because tetanus or rabies injections are made from horse serum, and this allergy can be life threatening-not being satisfied with one negative response, the computer says, "Think back now and be certain. Have you ever been given rabies or tetanus injections?" If the patient still says "No," it branches out and asks a general question, whether or not there have been allergies to any drugs not yet mentioned. This is a general screening question. We will answer "No" to this question, but if the answer were "Yes," then the patient could type in the name of the drug, and that would become part of the record.

"Have you ever had eczema?" This is associated with allergic disorders. We will say "No."