COMPUTERS

AND

BIOMEDICAL

On-Line

RESEARCH

Medicaid

(1975)

8,479491

Billing

System

EMMANUEL

for Physicians’

Services*

MESEL

Departments of Information Sciences and Pediatrics, University of Alabama, Birmingham, Alabama 35294 AND DAVID

D. WIRTSCHAFTER

Departments of Information Sciences and Pediatrics, University of Alabama, Birmingham, Alabama 35294 Received May 24,1974 An on-line Medicaid billing system for physicians’ services was implemented and tested during a 23 yr period in 100 offices throughout the state of Alabama. Participating physicians represented 17 % of all physicians in the state. Users entered data on standard Touch Tone (R) telephones equipped with card-dialers and received instructions and data confirmation from the central computer facility via voice answer-back. Input time for the average claim billing for two separate services was less than l+ min and resulted in a reduction of labor required for manual input by at least 50%. Editing of data at the source completely eliminated transmission of claims with erroneous patient identification numbers and also reduced errors in encoding procedures and diagnoses to an insignificant level, PERSPECTIVE

The cost of submitting an insurance claim for professional services is a disproportionate fraction of the amount paid for providing the service (I). For general practitioners, who provide the largest number of individual services, this share may be more than one fourth of the payment for most common services. Submitting a claim involves furnishing approximately 15 items on a standard form, usually in the following sequence: (1) determination of eligibility or contract number for services under a sponsored program (Medicaid, Medicare), or private insurance; (2) recording of demographic information, usually a transcription from business records; (3) abstracting and transcribing of services and diagnoses from the clinical record; (4) obtaining the patient’s and the physician’s signature; (5) making a copy of the claim for office records; and (6) mailing the claim to the intermediary or carrier. Most of these steps represent the recording of information twice, once for * This work supported by Contract HSM 1 lo-71 -252, Health Care Technology Division, National Center for Health Services Research and Development. 479 Copyright 0 1975 by Academic Press, Inc. All rights of reproduction Printed in Great Britain

in any form

reserved.

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business and once for clinical purposes. If some of the steps could be eliminated. the cost of submitting claims would be substantially reduced. Similarly for the insurance carrier or Medicare or Medicaid intermediary. the cost of preparing and recording data from source documents is a large part of total processing cost. For most claim processors, it takes three steps to convert source documents into computer usable form : ( I ) checking the claim to be sure it contains all necessary data; (2) encoding of procedures and diagnoses; and (3) translation of the data into machine readable form (cards, tapes. disks). Processingcosts would be substantially reduced if these labor-intensive steps could be eliminated. To put the problem in more concrete terms, it is estimated that the cost IO physicians to prepare insurance claims varies from $I .25 to $2.50 (I), each claim composed of an average of two service items. Carrier performance data published by the Bureau of Health Insurance (2) shows that our local Medicare intermediary spent an average of $2.35 to process a claim in 1973. Thus the combined cost of billing and claims processing could average $3.60 to $4.85 per claim. This estimate would be even higher in Washington, DC, and Chicago, IL. where claims processing costs alone exceed $4. Comparison of claims preparation and processing costs with the average per claim payment for ambulatory medical services of $10 (personal communication: Equitable-Alabama Medicaid office) demonstrates the need for reducing paperwork, especially multiple transcriptions of the same data elements in provider offices and carrier systems. Under sponsorship of the National Center for Health Services Research and Development, and with the cooperation of the Medical Services Administration of the State of Alabama, Blue Cross--Blue Shield of Alabama, and the Equitable Life Assurance Society, the Clinical Information Systems group of the [Jniversity of Alabama in Birmingham (UAB) contracted to design a system using point-ofservice terminals tied on-line to a central computer in a project to reduce the costs of. submitting claims from the physician’s office as well asthe costs of data preparation in the carrier’s system. Wl~y an On-Line System? The Bureau of Health Insurance has found that 151’, of all Part B Medicare claims become rejects within a carrier’s system becausethe patient’s identification number for benefits is invalid (3). A major source of annoyance and expense to both providers and carriers is the return of such claims for correction not only of identification numbers but of other data elements as well. By editing the inputs at their source and providing branching capability to handle complex transactions (e.g. the medication and volume injected for an “injection procedure,” “time” for anesthesiology procedures, etc.), much of the frustration and cost of the manual processing can be eliminated. Direct interaction also permits entry of multiple procedures in one claim transaction, entry of multiple diagnosesfor a single procedure, and switching between slow and painstaking instructional and fast, eficienl

ON-LINE

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BILLING

SYSTEM

481

modes of data entry. Imprinting with embossed plastic cards like a credit card used to prepare gasoline charge slips, and also used for pharmacy claims in the Alabama Medicaid Program, was considered impractical because of limited input capabilities. Choice of Data Entry Systemfor the Physician’s Ojice Since physicians are universally involved in billing third-parties, it was apparent that the cost of the terminal chosen for the physician’s office would be the major determinant of the cost of the total hardware package neededto operate the billing system. For a group of 1000 physicians (there are 2500 potential usersin Alabama) the least expensive video or printing terminal would cost five to seventimes asmuch as a voice answer-back system using a standard telephone set equipped with a numerical keyboard and card reader (Touch Tone (R) pad and Carddialer (R)). The incremental cost for hardware to an office already equipped with a telephone is lessthan $8 a month including a pro-rata share of the voice answer-back device. For a group as small as 100 users,the cost to each user would be lessthan $25 per month. System Specifications To provide satisfactory service to usersthe following general functional specifications were considered essential: (I) The systemshould operate continuously from 9 am to 7 pm, Monday through Friday. (2) The user should be able to enter 997: of all claims without resort to manual preparation of a document. (3) The user should be able to determine patient eligibility before completing a claim. (4) All data elementsentered must be edited. (5) Instructional and fast modes of operation must be provided. (6) A claim control number must be assignedto each claim entered and fed back via voice answer-back to the user for easy reference if later communication with the carrier becomesnecessary. (7) Accuracy of transmissionand encoding of information should equal the present manual systemat the very least. (8) The systemmust be capable of expansion to accept data not currently on claims but which will probably be required for PSRO purposes, e.g. results of laboratory tests, the blood pressuremeasurementfor hypertensive patients, etc. Design, Development and Operation The following sections describe the design, development, and operation of an on-line systemfor professional servicesbilling to the carrier in a statewide Medicaid program in Alabama. Software development began in July of 1971. The voice answer-back equipment and telephone interface were installed in late November

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and service to users began on December 13,197 I. The system has been in continuous operation providing 40 hr per week scheduled service since that date. A total of 165 845 complete claims representing 319 246 “lines” or individual services had been entered by the termination of the contract on April 30, 1974. During September 1973. the last month of free service, the volume entered exceeded 50 )!,; of the statewide load. At that time there were I 10 offices participating in the project billing for services provided by 343 physicians accounting for 17”,, of all providers of service in the Alabama Medicaid program. From October, 1973, through April, 1974, computer services were provided at the rate of 25e per billed medical service. During the 7 months of fee-for-service operation, 65 872 claims were entered compared with 76 361 during the previous 7 months of free service. METHODS

I. The Basic System Access to the system was provided via the “dial up” telephone network using modems (Bell 403D3) to decode the multifrequency tones and to interface the user terminals to the voice answer-back device, which was directly connected to the central processor. The funding agency made the initial decision to append the on-line hardware to the UAB central computer facility’s main-frame computer (rather than to support an independent preprocessor), so the choice of rentable voice answerback equipment was limited to IBM’s Audio Response [Jnit 7770 and associated 8721 vocabulary drum. A tentative vocabulary was selected from IBM’s library of recorded words to support the claims application expeditiously. Words not available were generated by spelling the word (or contraction) letter-by-letter. 4 revised vocabulary later replaced this clumsy procedure. The various files that support the on-line system as well as the file of incoming claims transactions are stored on an IBM 3330 disk drive. A dedicated core partition on the 370/l 58 handles programs for line-control of incoming claims and the interactive user dialogue. To enhance exportability a determined effort was made to write programs in a 32K core partition so that these same programs could be run on smaller stand-alone systems. 2. Recruiting Participating

Physicians

To determine which providers generate the highest volume of paperwork (dollar volume of claims is not indicative because of the high unit value of surgical procedures), we sorted the paid claims data for 1971, and ranked physicians according to the total number of “lines” submitted. (A “line” on a claim refers to a single service to the patient). Recruiting for participation in the project was directed primarily toward the 300 providers who accounted for two-thirds of all services to beneficiaries of the Medicaid program. Most of these physicians were in general practice.

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MEDICAID

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SYSTEM

3. On-Line System Software Line control. This program was written with the constraint that it be flexible enough to work in a highly interactive environment. Unlike most commercial applications of voice answer-back, it involved a complicated flow of data and messages. A simplified version of the user-machine dialogue is shown in Table I _ TABLE

1

SIMPLIFIED USER-MACHINE DIALOGUE FORINSTRUCTIONAL INPUT User input

Voice message

“Medicaid claim system, slow input, 4337 enter doctor number” “Enter patient number” 337-1-123456-789 “Enter “Enter “Enter “Enter

date” point of service” number of visits” procedure code”

“Enter diagnosis code” “Enter next diagnosis, or sign (#) to proceed” “Enter charges” “Charges seven point five zero” “Claim seven four six”

040174 1 1 90040

5020 # 750

Edits performed Checks for valid number in provider file Calculate check digit Check patient eligibility in recipient file Check for valid date or range of dates Check for valid point of service code 1 < Number < 99 Check for valid procedure code Program branches and asks for additional input for the following procedures : 90030 Injection (drug code, volume) 40XXXXX Anesthesia (time) 12000 Suture laceration (length) Check for valid diagnosis code Check for valid diagnosis code or “ # ” Check for valid range of charges Check for a valid code

:User records claim control number)

Mapping of claimform onto transactionfile. To make the on-line systemcompatible with the manual system employed by the insurance carrier (Blue Cross-Blue Shield of Alabama), the Medicaid claim form M-19-65 was mapped onto the transaction file carried on disk with a few minor changeswhich were agreeableto the carrier. Instructional/quick modesof data entry. Two voice answer-back procedures were implemented to accommodate novices and experienced users. The instructional mode guides the novice who is learning to use the terminal. A series of messages prompts the user through step-by-step entry of each required data element. Each entry is edited

and accepted

only when in the proper

range for that element.

Error

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MESEL

AND

WIRTSCHAFTER

messages are generated when faulty data are detected. As the userbecomesproficient, the prompting messagesbecome annoying and unnecessary. At this point the user can selectthe quick entry mode for data entry. In this mode, the user enters a stream of input interrupted after each data element by an audio tone from the computer to indicate a valid element has been received. Only two voice messages are generated : one after “charges” are entered to permit the userto recheck the entry. the other gives the user the claim control number for that claim. Both modes of data entry are completely compatible, and a user may switch back and forth from one to the other during a single transaction. Eligibility check. The system can respond to inquiries t’rom doctors’ offices. county health clinics, administrators in Medical Services Administration. and the insurer by supplying current eligibility information on any of the 300 000 recipients in the Medicaid Program so that providers of costly services can determine it’ a given patient is eligible for benefits. Prepwdled card l:eriJication. To verify the accuracy oE the prepunched cards used for much of the data entry, cards can be read by the terminal and interpreted by voice answer-back. Injectable medications~-a spec@ problem. Approximately two-thirds of ail claims processedby the intermediary contain a charge for an injection. Therefore, one of the potential stumbling blocks in automating claims processing was the handling of charges for injectable medications in doctors’ offices. In traditional systems. processing injections requires a manual “look-up” and setting of‘ ;III allowable charge for the procedure. Irrespective of the drug injected, the code 90030 (injection) is assignedto all such transactions. To facilitate automation. we prepared a list of ail injectable drugs found in the computerized Drug Product Information File (DPIF) of the American Society of Hospital Pharmacists(ASHP), and the unique five digit number. the DPIF Brand Product Package Number (BDPPK+‘)), was chosen as the code number to identify the drug injected. In OUI system, each time the procedure code number 90030 isencountered in a transaction. the user is asked to enter the drug code (BDPPK-$ ) and the volume given. Since \+e also have the average wholesaleprice for each drug in our file. it would be a simple matter to dcdate the allowable charge, compare it with the submitted charge, and determine which is lower. This degree of automation is lacking in currcnl carrier processingsystems. Procedure modfiers. Procedure modifier codes,two digit prelixes to the A MA-VP1 procedure codes discussedbelow, were adopted to cause program branching when claims for anesthesia, assistance at surgery, multiple surgical procedures, etc... were being entered. This allows the fiscal agent to determine allowable charge5 since special procedure codes do not exist for ail possible anesthesiaprocedures. e.g. anesthesiafor tonsillectomy. (There are more than 2500 surgical procedure codesalone!) We are indebted to the 1969California Relative Value Study for the concept of modifiers to reduce the number of procedure codes required.

ON-LINE

4. Of-Line

MEDICAID

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485

System Software

Off-line programs have been written to convert the transaction file on disk into hard copy claims and tape files for submission to the insurer. The data elements entered by the user are listed in Table 1. Other items needed to produce a hardcopy claim were retrieved from off-line files. To avoid manual translation errors, we printed both the AMA-CPT and the local carrier’s procedure codes. The claim control number, which was “voiced” to the user at the time of input, was also shown on the document. By arrangement with the Medicaid program director, no signature was required to submit these claims for payment. Eligibility Jile. A disk resident file of all current recipient numbers is created monthly from the eligibility tape file supplied by Medical Services Administration. It occupies 15 cylinders on an IBM 3330 disk pack. Cross-referencing procedure codes. To make the system generally applicable in claims processing, and to maintain impartiality toward all carriers, the American Medical Association’s Current Procedural Terminology (CPT) code was selected. Though the text descriptions of the codes are sometimes lengthy and circuitous, they represent a great deal of thought by the medical profession and the list is complete. We have also acquired from OCHAMPUS (Office of Civilian Health and Medical Programs for the Uniformed Services) a cross reference between CPT and 1964 CRVS, and CPT and the 1970 National Association of Blue Shield Plans (NABSP) procedure codes to expedite cross referencing between AMA’s CPT and Equitable’s and Blue Cross’ codes, derivatives of 1964 CRVS. Diagnosisjle. The complete set of 4 digit codes and their descriptions abbreviated to 90 characters (for purposes of hardcopy formatting) were keypunched from the eighth revision of ICDA, International Classification of Diseases, Adapted. Provider file. Physicians are identified by a 5 digit code supplied by Blue CrossBlue Shield of Alabama, the Medicare intermediary for this state. Monthly updates of this file keep our file current. 5. Aids to physicians’

ofices

Prepunched cards. Analysis of paid claims records for 1971 furnished by Equitable showed that the 10 commonest procedures accounted for more than $ of all services and the 50 most frequent diagnoses for more than + of all conditions submitted by all physicians participating in the program regardless of specialty. The paid claims file was further sorted by specialty of practice: for each specialty, procedures performed and patient diagnosis were ranked by frequency of occurrence and prepunched decks of the 50 most common procedures and diagnoses for the type of practice were distributed to each participant. The paid claims file was also scanned for recipients seen by any of the physicians participating in this project and cards were prepared for each patient except where the number seemed excessive; in these cases, cards were prepared only for patients

486

MESELAND WIRTSCHAFTER

with five or more visits. The prepared patient cards were distributed to the appropriate physicians. User instruction. Each user in the office of a participating doctor was trained by one of our instructors until competent to enter claims without assistance. Six hours of instruction, divided into three 2-hr sessions,was usually required. RESULTS

Physician Participation Our minimum performance goal was to enlist the participation of enough physicians to account for 50‘A of the statewide Medicaid billing load, using a maximum of 150 terminals. By September, 1973, we had agreements to participate with 1IO offices, but 10did not yet have the phone equipment becauseof problems with small independent phone companies in rural areasof the state. Of the remainder, 70 were submitting claims weekly and another 27 at least once monthly. Three did not use the system although adequately trained. Despite the small number of offices using the system regularly or intermittently, users entered 28 455 procedures in 14 368 complete claims during September 1973. This monthly rate exceeded the formal contract goal and was more than 50 p/i of the statewide load processedby the carrier. System Pet-fbrmance Time to enter claims. The histogram in Fig. I shows the distribution of the lime required to input claims. The small number of claims entered in less than 30 set represent claims submitted by six County Health Departments involving Pediatric Screening program visits. The average time to enter a claim, which usually contains two procedures, is lessthan lf min. The average time per procedure is consistently lessthan 1 min. Since some usersare still being trained, a few outlying claims take more than 7 min to enter. A maximum of 13procedures may beentered asone claim, but fewer than 1p;i of claims have so many procedures. TelephoneLoading The number of input channels required to handle a given billing load can be estimated from current experience. Table 2 shows the loading of the various telephone lines as a function of time of day for the last week of September 1973. It should be noted that although we made no attempt at scheduling input, users achieved a reasonable distribution of claims entry during the day and during the week. Because most high volume users are outside the local dial-up area of the central facility, we have installed three WATS lines in addition to two local lines. These five lines easily handle 5006 of the statewide load-our project goal. (Our original projections were that 13 lines would handle lOO”/ of the load-based on a I-min average time per “line,” a 507/, duty cycle for a phone line, and 40 hr/wk operation.)

ON-LINE

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SEPTEMBER,1973

L 2.5

TIME

3

3.5

4

4.5

5

5.5

6

IN MINUTES

FIG. 1. Distribution of time to transmit complete claims. The average number of services per claim is 1.9. Data for September 1 to September 28,1973, the last 4 wk of free serviceand the highest volume period during the project. TABLE SYSTEM

Hour

LOADING

AS A FUNCTION

2

OF DAY

OF WEEK

Number of Claims Tuesday Wednesday

Monday

AND

TIME

OF DAY’

Thursday

Friday

0 112 159 193 129 112 142 120 113 84 48 1212

8 145 123 105 65 67 102 79 136

.~~ 8-9 9-10 IO-11 11-12 21-1 l-2 2-3 3-4 4-5 5-6 6-7 Total L?Data

0 7 123 173 31 76 55 133 50 23 0 671

38 67 104 77 70 93 136 123 86 66 64 924

for last week of September 1973.

25 205 146 153 157 165 150 193 114 57 0 1365

1 10

841

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Acceptunce by Intermediary The initial cautious attitude of both carriers involved in this project has gradually moved toward more enthusiastic acceptance of the potential for cost reduction in claims processing, not only for Medicaid claims, but for their private Blue Shield contracts with subscribers as well. The carriers also realize that there is no basic: conflict between our system and their own efforts to implement “direct entry” ot claims, an improvement that eliminates the preparation of coding forms from standard source documents. Throughout the project the carriers processed hard copy produced by our system just like manually prepared claims submitted by other physicians’ offices. Although confident that the encoding of information by office personnel was accurate and that cross-referencing of CPT to local codes was also accurate, neither carrier processed claims directly from magnetic tape. Blue Cross tested the feasibility of processing Pediatric Screening claims and found no technical barriers to a successful outcome. but has been unwilling to attempt this on a general basis because of conflicting internal priorities. Cost Anu1,ysi.s The high volume achieved permits a realistic estimate to be made of the cost for providing on-line computer services for medical billing. Variable costs for computer processing need little extrapolation. The projected annual budget for a system which handles a minimum of 400 000 service entries per year assuming all reporting offices have been trained is approximately $100 000 including overhead based on a cost per unit of service billed of 256. Most offices report halving in personnel time required for billing and improved collections resulting from accurate and complete claims. DISCUSSION

The use of voice answer-back systems is not innovative in itself. These systems have been used extensively by the banking industry for simple account balance inquiry systems, by industry for inventory control, and tracing jobs within a plant. Experimental work in the biomedical field was reported by Allen and Otten (4) who demonstrated the applicability of such systems to medications ordering, laboratory test ordering, and inquiry systems on an experimental basis. The novelty in the application is in the complex data flow with extensive user-machine interaction and in the flexible branching program structure which can be expanded to obtain additional information for PSRO. This contrasts sharply with the imprinter billing system under consideration by SSA (3) which does not even capture diagnosis in machine readable form and is limited to “one procedure” claims. We gained a number of revealing insights in the process of training doctors‘ office personnel to use the on-line system. Frustrated by previous experience with the bureaucracy, the physician’s role in claims processing is often passive/aggressive.

ON-LINE

MEDICAID

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A physician, who is either too busy to care or unaware of the significance of how the procedure or diagnosis he specifieson a claim form is translated into a code by the intermediary, may use nonstandard terminology to describe servicesrendered, not realizing the effect this may have on reimbursement. When payments for services are not checked against the claim submitted, a feeling of hostility may develop when the physician finds that payment for the same service varies and he may refuse to seeother sponsoredpatients. Errors generated in the processof translating procedure descriptions to procedure codes were estimated by comparing a list prepared manually by the office clerk working for each physician with a comparable list derived from paid claims data supplied by the intermediary. Except for two of the most common services(“routine office visit” and “initial office visit”) these two lists did not coincide for general practitioners and surgeons. In contrast, the agreement for radiology and clinical pathology laboratories was excellent. The discrepanciesnoted indicate that coding of procedure by the intermediary may be too subjective or too arbitrary, or, more likely, that the physician did not state clearly and explicitly what services he prcvided. It is clear that laboratory and X-ray examination descriptions are concise, and that there is adequate standardization of terminology for these procedures among all physicians. Surgical procedure names, on the other hand, are notably nonuniform. There is enormous variance between the AMA-CPT, the NABSP? and the 1964 and 1969 CRVS procedure code manuals; and enormous variation among individual physician’s descriptions of these procedures. Installing a telephone terminal to the on-line system and attempting to use the system has brought these problems into clear focus for the average physician for the first time. Use of the systemrequires a certain discipline not always typical of a doctor’s businessoffice. A clerk who understands the encoding of procedures and diagnoses must often ask the physician many questions to resolve an ambiguous description. (Some personnel state they had never previously dared question the physician about what he had written on a claim form.) When an office goes“on-line,” there is a period of about 1 wk during which the usermakesobvious mistakes,revealed by direct manual comparison of our hardcopy with office records. After this initial period, errors in encoding procedure and diagnosis with the on-line systemare lessthan I 1’;. The difference between new and old systemsis undoubtedly a reflection of the various “edits” that are built into the on-line system, and a new awarenessof what the whole processof claims processing involves on the part of doctors’ office staff. A positive conclusion on cost-effectiveness cannot be made at the present time. This crucial issuecan be resolved only by objective cost accounting studiesof the on-line billing system, physicians’ businessoffice, and carrier operations. It has been very difficult to obtain cost data from carriers either because most customary carrier accounting methods aggregate costs into centers that are not directly comparable to the functions performed by our on-line billing system, or becausecarrier

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operations are highly competitive business enterprises, these data are closely guarded businesssecrets. Anecdotal evidence from several of our high-volume group practices indicates that the labor cost has been reduced to one third the previous cost using manual methods. If this proves to be true for small offices as well, a significant cost reduction to physicians’ office operations aswell asofcarrier’s should be possible.

The following conclusions may safely be drawn from our experience in operating the system: 1. The numeric keyboard/card dialer telephone used in conjuction with audio feedback via computer is completely adequate for gathering and editing data to produce a physician’s claim for service in the Medicaid program. 2. Fifty prepunched cards for procedures and diagnoses,when carefully selected for the individual office, reduce manual entries of these data elementsto fewer than 5yi of the total number entered. 3. User acceptance of this mode of data entry is conditioned to a large degree by the type of practice (group vs solo practitioner) and the amount of basic office organization predating the installation of the terminal. With persistence, however, reluctant users can be retrained to take advantage of this system, This may be accompanied by improved performance in other aspectsof office management. ADDENDUM

Those readers interested in obtaining additional software documentation should addresssuch a request to the Director of Health Care Technology, National Center for Health Services Research,Parklawn Building, Rockville, MD 20852. ACKNOWLEDGMENTS The authors wish to acknowledge the assistance and cooperation of the following individuals and groups without whose help this project could not have succeeded: all our physician participants and their office staffs: Dr. Paul I. Robinson, Director of MSA (Medicaid); Dr. Thomas H. Alphin, previous Director of MSA; Mr. Joseph Vance, Senior Vice-President of Blue Cross-Blue Shield of Alabama, Mr. John Anderson, District Director of Equitable-Alabama Medicaid: Dr. Robert Holzworth of OCHAMPUS; Dr. William Barclay of AMA: Dr. Josiah Macy, Jr., Director of the Division of Biophysical Sciences of UAB; Mr. Jack Davis, Manager of Operations for UAB Central Computer Facility; and to MS. Sybil Klein, Ms. Betty Doyle, and Ms. Sandra Brown former and present project managers without whose patience, encouragement, devoted service, and loyalty this effort would not have gotten beyond the initial feasibility study.

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REFERENCES 1. KRMSKY, JOEL AND HAMPTON, PHILLIP Community Profile Data Center, Technical Paper Series No. 2, Contract HSM-110-70-43, Community Health Service, HSMHA, DHEW. 2. Statistical Report on Administration Costs for Medicare contractors, July 1973 through December 1973, Bureau of Health Insurance, Social Security Administration. 3. Report on Simplified Physician Billing Project. Division of Systems, Social Security Administration, April 1973. 4. ALLEN, SCOTT I. AND HEN, MICHAEL. The telephone as a computer input-output terminal for medical information. JAMA 288,673-679 (1969).