* 

FROM VITAL & HEALTH STATISTICS OF THE NATIONAL CENTER FOR HEALTH STATISTICS 

U.S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE � Public HealthService I Number15¤ Decernlwr14,1977 

National Ambulatory Medical Care Survey of Visits to 

General and Family Practitioners, January-December 19751 

o 

* 

According to data collected in the National 

Ambulatory h4edical Care Survey (NAMCS), an 

estimated 234,660,000 visits were made to the 

o f f ices of general and famiIy practitioners 

(GFP’s) during calendar year 1975. These visits 

accounted for over 41 percent of the estimated 

567.6 million visits made to all office-based physicians in 1975. 

The NAMCS is a sample survey designed to 

explore the provision and utilization of ambulatory care in the physician’s office-the setting 

where most Americans seek health care. The survey is conducted yearly over the coterminous 

United States by the Division of Health Resources ‘Utilization Statistics of the National 

Center for Health Statistics. The survey sample 

is selected from doctors of medicine and osteopathy who are engaged in office-based, patient 

care practice. In its current scope, the NAMCS 

excludes physicians practicing in AIaska and 

Hawaii, physicians whose specialty is anesthesiology, pathology, or radiology, and physicians in 

Government service. 

For a Iisting of publications describing fi-e 

development of the survey and definitions of 

terms used in the survey see the Technical 

Notes. A detailed explanation of the sample 

design and the reIative standard errors associated 

with selected aggregate statistics may be found 

in that section. 

1~hi~ report was prepared by Beulah K. CYPress! 

Ph.D., Ilivision of Health Resources Utilization Statistics. 

Provisional NAMCS data for calendar year 

1974 regarding general and family practitioners 

have been published.z Caution should be exercised in making comparisons between 1975 estimates and the provisional 1974 estimates previously published. Since the 1974 provisioned data 

were released, refinement of the procedures used 

to project the national estimates from the sample findings has resulted in a lowering of the 

final 1974 numerical estimates of office visits by 

8 to 9 percent. In particukw, the provisional estimate of 263.4 million office visits to general and 

family practitioners in 1974 was finalized to reflect the more accurate figure of 242.9 million 

office visits. FinaI distributions and percents, 

however, were virtuaIly unchanged. The number 

of total office visits for all specialties for calendar year 1974, estimated at 634.1 million in the 

previous publication, has been adjusted to 577.8 

milIion.3 

2 National Center for Health Statistics: National Ambulatory Medical Care Survey: National Ambulatory 

Medical Care Survey of Visits to General and Family 

Physicians, January 1974December 1974. Monthly 

Vital Statistics Report. Vol. 25-No. 2, Supp. 2. DHEW 

Pub. No. (HRA) 76-1120. Health Resources Administration. Roclwille, Md. May 19, 1976. 

3National Center for Health Statistics: Ambulatory 

medical care rendered in physicians’ offices, United 

States, 1975. Advance Data From Vital and Health 

Statistics, NO. I 2. DHEW pub. No. (HRA) 77-1250. 

Health Resources Administration.. HyattsvilIe, Md. octtober 12, 1977. 
---------------

-------

-------------

--------------

---------

2 achancedata 

DATA HIGHLIGHTS 

A comparison of visits made to office-based 

physicians in the most-visited specialties reveals 

that visits to GFP’s during 1975–234.7 million–exceeded the total estimated visits to the 

next four leading specialties combined–1 98.2 

million (table 1). 

Table 1. Number and percent of visits to


office-based physicians, by the most-


visited specialties: United States, Jan­


uary- December 1975


of Per-


Most-visited vis its cent


specialty in of


thou- yis its


sands


GENERAL AND FAMILY


PRACTICE 234,66C 41.3 

Internal medicine 62,111 10.9 

Obstetrics and 

gynecology 48,07C 8.5 

Pediatrics 46,684 8.2 

General surgery 41,29> 7.3 

Type and Location of Practice 

More visits were made to general and family 

practitioners electing solo practice—73 percent—than to physicians having group or partnership arrangements—27 percent (table 2). This 

reflects the fact that about 74 percent of GFP’s 

were engaged insolo practice in 1975. 

While visits to the offices of GFP’s located 

within standard metropolitan statistical areas 

(SMSA’S)4 outnumbered visits to nonmetropoliAAn SMSA is defined as a group of contiguous counties containing atleast one cityof50,000inhabitants or


more, or two contiguous cities with a combined population of at least 50,000 inhabitants. The distinction 

“metropolitan/nonmetropolitan” should not be confused with “urban/suburban” or “urban/rural” since an 

SMSA may contain urban, suburban, and rural subsections. 

tan-based offices (table 2), there was less disparity between location categories than appeared 

in other specialties. Table 3 illustrates this &lfference. 

A greater number of visits to metropolitanbased GFP’s is reasonable since about 70 percent 

of the population resides within SMSA’S, and 

approximately 65 percent of physicians in general and family practice are located within 

SMSA’S. However, the annual rate of visits to 

nonmetropolitan offices of GFP’s (146 visits per 

100 persons) was more than half again as much 

as the rate within SMSA’S (94 visits per 100 persons)—an indication that the population outside 

of SMSA’S tends to visit GFP’s more often than 

those within SMSA’S. 

Patient’s Age, Sex, and Color 

The number of visits to office-based general 

and family practitioners increased with age, the 

greatest number occurring in the age interwd 

from 45 to 64 years (table 2). For persons 65 

years and over, the rate of annual visits was triple the rate for persons under 15 years of age. 

Visits by females outnumbered visits by 

males by a ratio of about 3 to 2 (table 2). Further, the tendency of females to make more 

visits to the physician was clearly reflected in 

their higher rate of annual visits. For every 100 

persons; there were 130 visits by femziles. For 

males, this rate was 95 visits for 100 persons. 

Table 4 shows the influence of sex and age 

on percent and annual rate of visits. Female 

visits exceeded male visits in every age, category 

except that under 15 years. 

White persons (88.5 percent ) outnumbered 

all other persons (1 1.5 percent) in ofilce visits to 

GFP’s (table 2). The annual rate of office visits 

was also higher for white persons than for the 

rest of the ~opulation. The~e data could indicate” 

that members of other races availed themselves 

more often of other means of ambulatory medical care since the NAMCS includes only officebased care. 

Visits described by the joint classification, 

white and female, were greater than by any * 

other combination of sex and color as shown in 

table 5. 
.

------- ------- ------- ------- ------- ------- -----------------------------------

----------------------------------- --------------------------------

---------------------- ------------------------------------

------------------------------------

-----------------------------------

-----------------------------------------

---

---

a&mdata3 

Table 2. Number, percent distributions, and number of visits per 100 persons per year


to office-based general and family practitioners by type and location of the physi-


cian’s practice and by age, sex, and color of the patient: United States, January-


December 1975


Selected physician and


patient characteristics


All visits-------------------------------


PHYSICIAN CHARACTERISTIC


/ Type of practice


solo ‘ -

Otherz -_----

Location3


Metropolitan


Nonmetropolitan
 0 PATIENT CHARACTERISTIC


Age 

Under 15 years-----------”


15-24 years


25-44 years


45-64 years -


65 years and over------------------------------


Sex


Female


Male-------------------------------------------


Color


White------------------------------------------


Number of


visits in


thousands


234,660


171,010


63,650


136,533


98,127


33,772


37,568


56,476


64,502


42,343


138,904


95,756


207,660


0ther4----------------------------------------- 27,000


.


Percent


distributions


of visits


100.0 

72.9


27.1


58.2


41.8


14.4


16.0


24.1


27.5


18.0


59.2


40.8


88.5


11.5


Number of


visits per


100 per-
 sons per


yearl


113


94


146


65


96


108


152


194


130


95


H5


99


lBased on population estimates for July 1, 1975, Bureau of the Census, Current Pop­


ulation Reports,,Series P-25 and P-26.


‘Includes partnership and group practices.


3Signifies location within or outside the standard metropolitan statistical areas
 (sMSA’s).


‘ 40f ibis category, about 81 percent are visits by blacks.


Major Reasons for Visit 

forvisitrecordedby thephysickm asnearlyas


The dataconcerningthemost frequentcom- possiblein the patient’s
 � own words.The broad


plaints,symptoms, or other reasons for a clinical
 range of the GFP’s practiceisdemon­


patient’s
visit(table6) were derivedfrom an stratedby the factthatitrequired18 reasonsto 

item on the surveyform thatelicited t.hereason accountforonlyhalfof allvisits.

-----

----------

-----

-----

-----

-------------------

---------------

o 

4 

Table 3. percent distribution of visits Table 5. Percent of visits to office-


to office-based physicians by location, based general and family practitioners,


according to specialty: United States, by s,ex and color: United States, Jan-


January-December 1975 uary-December 1975


Gen- Percent of
 Ob­
 eral all visits
 Inter- stet-
 and nal rics Pedi- Color of patient


Location fam­
 medi- and atrics ily Female Male 

prac- cine gyne- 1-1-

tice Cology


I i 1 White 52.1 36.3 

All other 7.1 4.4 

Percent distribution 

of visits 

Total--- 100.OI 100.OI 100.01 100.0 

visits
involvedprenatalandpostriatalcare.Ordy


Metropol- the obstetrician-gynecologist
 exceeded theGFP 

itan
 in the number of visits for these three reasons. Nonmetro­


politan--


Principal Diagnosis 

Table 7 lists the 25 most common principal 

diamoses assi.smed by GFF”S to office visits. 

Table 4. Percent and annual rate of visits to office-based general and family Th&ediagnose; constituted about one-halfof all 

practitioners, by sex and age of the visits macleto office-basedGFP’s in 1975. 

patient: United States, Jantiary-Decem- Table 8showsthe number ofprincipal diag­ ber 1975
 noses according to major ICDA5 groups. The 

following four diagnostic groups account for 

Annua 1 slightly more than 50 percent of all principal 

Percent of rate of diagnoses rendered: 

Age of 

patient 

100 persons Diseases of the respiratory system, 

Special conditions and examinations without sickness, 

Fe- male ‘Male Fe- Male male 

Diseases of the circulatory system, 

Accidents, poisonings, and violence. 

Under 15 I 

years 6.5 7.8 1:: 69 Diagnostic and Therapeutic Services 

all visits visits per 

T 

15-24 years


25-44 years 1;:; $:: 133 i? Limited or general histories and examina-


45-64 years 16.8 10.7 178 123 tions were performed during about two-thirdsof 

Over 65 years--- 111.1 7.0 202 183 all general and family practitioner (GFP) office 

visits(table 9). 

Blood pressure checks, performed during40 

Dercent of all GFP visits, were done frequently . . In examining the major reasons for a visit 

shown in item 8 of the Patient Record form, it is 

estimated that over 2 million visits at least partly 5Eighth Revision International Classification of Disinvolved family planning, and over 6 million eases, Adapted for Use in the United States (ICDA). 
Table 6. Number, percent, and cumulative percent of visits to office-based general and


family practitioners, by the 25 most frequent patient problems, complaints, or symptoms classifiedby the National Ambulatory Medical Care Survey (NAMCS) symptom classification code: United States, January-December 1975 

— 

Number of Percent
 Most frequent patient problem,


percent
 Rank complaint, or symptom and NAMCS codel visits in of Cumulative


thousands visits


1 

2


:


5


;


8


1;


11


12


13


14


15


16


17


18


19


20


21


22


23


%


General and required physical


exanrLnations-----------------------------9OO,9Ol


Problems of back------------------------------4l5


Throat soreness-------------------------------52O


Problems of lower extremity-------------------4OO


Abdominal pain--------------------------------54O


Problems of upper extremity-------------------4O5


Cough-----------------------------------------3l~


Visit for medication--------------------------9lO


;~;;gue---------------------------------------OO4


------------------------------------------312


Headache--------------------------------------O56


Pregnancy examination-------------------------9O5


Pain in chest---------------------------------322


Allergic skin reaction------------------------ll2


Wounds of skin---------------------~----------ll6


High blood pressure---------------------------2O5


Surgical aftercare----------------------------986


Weight gain-----------------------------------OlO


Vertigo— dizziness----------------------------O69


Problems of face, neck------------------------4lO


Earache---------------------------------------735


Fever-----------------------------------------OO2


Gynecologic examination-----------------------9O4


Shortness of breath---------------------------3O6


Flu-------------------------------------------3l3


11,582 4.9 

9,535 4.1 

9,005 

8,847 ::: 

7,279 3.1 19.7 

7,234 3.1 22.8 

7,046 25.8 

6,436 ;:; 28.5 

6,221 2.7 31.2 

6,077 2.6 33.8 

5,836 2.5 36.3 

5,709 2.4 38.7 

4,919 2.1 40.8 

4,711 2.0 42.8 

4,576 2.0 44.8 

4,432 1.9 46.7 

;,::: 1.9 48.6 

1.6 50.2 

3;554 1.5 51.7 

3,161 1.4 53.1 

3,147 1.3 54.4 

3,087 55.7 

2,749 ::: 56.9 

2,620 1.1 58.0 

2,560 1.1 59.1 

lSymptomatic groupings and code number inclusions are based on a symptom classification developed for use in the NAMCS.


forpatientsover44 yearsofage and rarelyfor 

patientsunder 15 years. For persons over 44 

years of age, 53 percent ofvisits incIuded determination of arterial pressure anclinordy 10percent of visits by patients under 15 years was 

arterial pressure measured. Drugs were the most 

common form of therapeusis. About 56 percent 

of visits resuIted in administration or prescrip ­

tionofdrugs. 

Prior Visit Status 

� Patients tendedto remain under the care of 

the same physician since 7 of 8 visits to GFP’s 

were made by “old” (returning) patients (table 

10). Of these, about two-thirds related to problems the physician had treated previously. 

Seriousness of Problem 

The data on seriousness of probIem expressed the physician’s judgment as to the extent of impairment that might result ifno care 

were available for the given problem. They 

shouldbe viewed in the context of the natureof 

the specialist’s practice. 

Problems presented by patients when visiting 

the office of the GFP tended toward the lower 

range of the “seriousness” scale (table 10). The 

largest proportion of visits (48 percent) were 

0 
6 aciwlncedata 

Table 7. Number, percent and cumulative percent of visits to office-based general and


family practitioners. by the 25 most common ICDA-coded DrinciDal . . diamosis! United

States,‘January-Decernbe%1975 

Number


of Per- Cumula-


Rank Most common principal diagnosis and ICDA codel visits cent tive
 in of


thou- visits percent


sands


!edical or special examination----------------------YOO 14,690 6.3


Essential benign hypertension-----------------------4Ol 13,904 5.9 1;:;


1


2


3


4 

2 

7 

8 

1: 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

$; 

23 

24 

25 

Acute upper .respiratoryinfection, site


unspecified----------------------------------------465


Diabetes mellitus-----------------------------------25O


!ledicaland surgical aftercare----------------------YlO


Acute pharyngitis-----------------------------------462


Chronic ischemic heart disease----------------------4l2


)ther eczema and dermatitis-------------------------692


Influenza, unqualified------------------------------47O


3besity---------------------------------------------277


Yeuroses--------------------------------------------3OO


Bronchitis, unqualified-----------------------------49O


Acute tonsillitis-----------------------------------463


Arthritis, unspecified------------------------------7l5


Cystitis--------------------------------------------595


3titis media----------------------------------------38l


osteoarthritis---------------------------e----------713


Synovitis, bursitis---------------------------------73l


Other nonarticular rheumatisrn-----------------------7l7


Diarrheal disease-----------------------------------OO9


menopausal symptoms---------------------------------627


Chronic sinusitis-----------------------------------5O3


Hay fever-------------------------------------------5O7


Sprains, strains of sacroiliac region---------------846


Inoculations and vaccinations-----------------------YO2


8,505 15.8 

5,780 ;:! 18.3 

5,602 2.4 20.7 

5,204 22.9 

5,141 ;:$ 25.1 

5,075 2.2 27.3 

4,927 2.1 29.4 

4,905 2.1 31.5 

4,126 33.3 

3,903 i:? 35.0 

3,884 1.7 36.7 

3,457 1.5 38.2 

3,203 1.4 39.6 

3,087 1.3 40.9 

2,895 1.2 42.1 

2,868 1.2 ::.; 

2,818 1.2 

2,709 1.2 45:7 

2,562 1.1 46.8 

2,546 1.1 47.9 

2,503 1.1 49.0 

2,437 1.0 50.0 

2,347 1.0 51.0 

lDiagnostic groupings and code number inclusions are based
 on the Eighth Revision


International Classification of Diseases, Adapted for Use in the United States.


rated“not serious”followedby about 35 per­


centrated“slightly serious.’’
 Only 17 percentof


visits
were judged “serious”or “veryserious.”


Since much of officepracticefocuseson pre­


ventiveand maintenance care,thisresultwas


predictable.


Disposition and Duration of Visit 

More than half(51 percent) of the visitsto 

the GFP resulted in the specific direction to return at a particular time (table 10). An additional one-third involved followup if needed or 

follovvupby telephone. Avery smaJI proportion 

(slightly more than 1 percent) of the GFP’s 

patients were admitted to a hospitaL This also 

supports the findings that ambulatory office 

care focuses on preventive care and health maintenance with an accompanying small proportion 

of cases judged “serious.” 

The average time spent in face-to-face encounter between the GFP and the patient was 

about 13 minutes, slightly less than the average 

time for the 13 most-visited specialties. While 

the duration of most visits was6-15 minutes (as 

evidenced by the average), the proportion of 

visits consuming 16-30 minutes tended to increase as the problems werejudged more serious. 
- -

----------------------------------

a&mdata7 

Table 8. Number and percent distribution of visits to office-based general and family


practitioners,by principal diagnosis classified by ICDA group:United States,January-


December 1975-


Percent
 Number of Principal diagnosis and distribu-
 visits in ICDA codel tion of
 thousands visits


All principal diagnoses 234,660 100.0 

Infective and parasitic diseases------------------------OOO-l36 

Neoplasms-----------------------------------------------l4O-239 

10,878 

2,795 

4.6 

1.2 

Endocrine, nutritional, and metabolic diseases----------24O-279 13,568 5.8 

Diseases of the blood and blood-forming organs----------28O-289 3,043 1.3 

Mental disorders----------------------------------------29O-3l5 7,064 3.0 

Diseases of the nervous system and sense organs---------320-389 10,906 

Diseases of the circulatory system----------------------39O-458 29,005 1::: 

Diseases of the respiratory system----------------------46O-5l9 43,304 18.5 

Diseases of the digestive system-----------------------52O-577 9,154 3.9 

Diseases of the genitourinary system--------------------58O-629 14,946 

Diseases of the skin and subcutaneous tissue------------68O-7O9 10,721 ::2 

Diseases of the rnusculoskeletalsystem------------------7lO-738 16,668 7.1 

Symptoms and ill-defined conditions---------------------78O-796 9,220 

Accidents, poisonings, and violence---------------------800-999 20,168 H 

Special conditions and examinations without sickness----YY13Yl3 30,188 12.9 

Other dia~oses2----------------------------------------------- 544 0.2 

Diagnosis “none” or unknown3----------------------------------- 2,486 1.1 

lDiagnostiC group~gs and code number inclusions are based on the Eighth Revision


International Classification of Diseases, Adapted for Use in the United States.


‘Complications of pregnancy, childbirth and the puerperium (630-678), congenital


anomalies (740-759), certain causes of erinatal morbidity and mortality (760-779).


sIncludes blank, noncodeable, and ilYegible diagnoses.

----------------------- ---------------------------

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-------------------------------------

--- ----------------- ---

----------------------- ---------------

---------------------------------- ----------------

--------------------------------------------

-------- -------------------------------------

-----------------------------------------------------

-------------------------------------------------------

--------- ----------------- --------------------------

-----------------------------------------

---------------------------------------------------

---------------------------------------------- ------ --- --------------- --

-------------------------------------------

8


Table 9. Number and percent distribution of visits to office-based 

practitioners by diagnostic and therapeutic services ordered or 

States, January-December 1975


Diagnostic and therapeutic service ordered or provided


All visits


No services provided


Diagnostic services: 

Limited history/examination 

General history/examination .-- --.--------

Clinical lab test -_------ -

X-ray ----.----

Blood pressure check


EW-------------------------------------------------------------


Hearing test - -.----


Vision test


Endoscopy


Therapeutic services:


Drug administered or prescribed2--------------------------------


Injection -.- -


Immunization/desensitization------------------------------------


Office surgery - -------.


Physiotherapy


Medical counseling


Psychotherapy/therapeutic listening - - -


Other services provided


general and family 

Provided: United 

Number of Percent


visits in of


thousands visitsl


234,660 100.0


4,082 1.7


130,516 55.6


29,570 12.6


50,618 21.6


14,638


94,358 4&;


5,418 2.3


1,831 0.8


3,307 1.4


1,474 0.6


n


130,479 55.6


50,476 21.5


8,659 3.7


12,113 5.2


7,834


27,378 1?:; 

6,715 2.9


8,451 3.6


1 

Percents will not add to 100 because most patient visits required the provision of more than one treatment or service. 

21ncludes prescription and nonprescription drugs.


—— _ ._—
-----------------------------------------

--------------------------

-----------------

-----------------

-------- -------- -------- --------

-- ---------------------------------

----------------------------------------------

-------------------------------------- ------------------

------- ------- -------- ------- ------- -----

--------------------------------------

----------------------- ------ ----------------------------------

---- ---------------- ---------------- ------------

------------------------------------------------ ---------------------------------------------

---------------------------------------------

--------------------------------------------

-------------------------------------------- --------------------------------------

dmcecMa9 

Table 10. Number and percent distributions of visits to office-based general and fam­


ily practitioners by prior-visit status, seriousness of problem, disposition and


duration of visit: United States, January-December 1975


Selected visit characteristic


All visits


Prior-visit status


Patient seen for the first time


Patient seen before—for another problem


Patient seen before—for current problem


Seriousness of problem


Serious and very serious -


Slightly serious ---..-


Not serious


-. Disposition] 

No followup planned


Return at specified time .--------------


Return if needed


Telephone followup -


Referred to other physician/agency


Admit to hospital


Other2 - - -


Duration of visit3


O minutes


1-5 minutes -


6-10 minutes


11-15 minutes


16-30 minutes


31 minutes or more -


Number of


visits in


thousands


234,660


29,847


71,446


133,367


39,941


82,440


112,279


36,326


120,379


68,444


8,658


6,957


2,861


2,276


3,885


48,156


79,964


:;,:;;


4;362


‘ercent dis­


tributions


of visit


100.0


12.7


30.5


56.8


17.0


35.1


47.9


15.5


51.3


29.2


3.7


3.0


1.2


1.0 

2A:;


34.1


24.9


17.0


1.9


1 

Percents will not addto 100 because some patient visits had more than one disposition. 

21ncludes return to referring physician.


3Signifies time spent in face-to-face encounter between physician and patient.

. .

. .. . .

. ... . ..

..

. . . .

... . .

. . .

.

.

..

. ...

10 acklncedata 

TECHNICAL NOTES 

SOURCE OF DATA: Data presented in this re- mate. Relative standard errors of selected aggreport were obtained during 1975 through the gate statistics are shown in table I. The standard 

Nat io nal Ambulatory Medical Care Survey errors appropriate for the estimated percentages 

(NAMCS). The target population of NAMCS en- of office visits are shown in table II. 

compasses office visits within the conterminous 

United States made by ambulatory patients to 

physicians who are pnncipidly engaged in office Table 1. Approximate relative standard errors of estimated numpractice. bers of office visits 

SAMPLE DESIGN: The 1975 NAMCS utilized a 

multistage probability design that involved samples of primary sampling units (PSU’S), physician practices within PSU’S, and patient visits 

within practices. Within the 87 PSU’S composing ~ 

500 .. .. .. . .. .... . .. . ... . ... .... .. .. ... .. . .... 30.1 

the first stage of selection, a sample of approxi- 1,000 ..................................... 21.4 

mately 3,500 physicians was selected from mas- 2,000 .................................. 15.3 

ter files maintained by the American Medical 

Association and the American Osteopathic Asso5,000 ................................ 

10,000 ................................... 

30,000 ................................. 

10.0 

7.5 

5.1 

ciation. Sampled physicians, randomly assigned 

to 1 of the 52 weeks in the survey year, were 

100,000 .............................. 

550,000 ................................ 

4.0 

3.5 0 

requested to complete Patient Records (brief en- Example of use of table: An aggregate of 80,000,000 has a counter forms) for a systematic random sample relative standard error of 4.3 percent or a standard error of 

of office visits taking place within their practice 3,440,000 (4,3 percent of 80,000,000). 

during the assigned reporting period. (A facsimile of the Patient Record used is shown in a 

previous issue of Aduance Data From Vital and Table II, Approximate standard errors of percentages for estiHealth Statistics, No. 12, October 12, 1977.) mated numbers of office visits 

Additional data concerning physician practice 1


characteristics such as primary specialty and


type of practice were obtained during an induc­


tion interview.


A complete description of the survey’s background and development has been presented in 

an earlier publication in Series 2 of Vital and 

1,000 ..................... 

3,000 .................... 

2.1 

1.2 

4.6 

2.7 

6.3 

3.7 

8.5 

4.9 

9.7 

5.6 

10.6 

6.1 

Health Statistics (No. 61. 6HEW Pub. No. 5,000 .................... 0.9 2.1 2.8 3.8 4.3 4.7 

(HRA) 76-1335. Health Resources Administra- 10,000................... 0.7 1.5 2.0 2.7 3.1 3.3 

50,000................. 0.3 0.7 0.9 1.2 1.4 1.5 

tion. Washington. U.S. Government Printing 100,000................. 0.2 0.5 0.6 10.8 1.0 1.1

Office, Apr. 1974). A detailed description of the 500,000 ............. 0.1 0.2 0.3 0.4 0.4 0.5

1975 NAMCS design and procedures will be 

presented in future publications. Example of use of table: An estimate of 30 percent based on 

SAMPLING ERRORS: Since the estimates for an aggregate of 75,000,000 has a standard error of 1.2 percent. 

The relative standard error of 30 percent is 4.0 percent (1.2 perthis report are based on a sample rather than the cent+30 percent). 

entire universe, they are subject to sampling variability. The standard error is primarily a measure 

of sampling variability. The relative standard er- ROUNDING: Aggregate estimates of office visits 

ror of an estimate is obtained by dividing the presented in the tables are rounded to the near- @ 

standard error of the estimate by the estimate est thousand. The rates and percents, however, 

itself and is expressed as a percent of the esti- were calculated on the basis of original, un-
---

ZKivancedata 11 

rounded figures. Due to rounding of percents,


the sum of percentages may not equal 100.0 per-


cent.


DEFINITIONS: An ambulatory patient is an in­


dividual presenting himself for personaI health


services who is neither bedridden nor currently


admitted to any health care institution on the


premises.


An o~~ice is a place that the physician identifies as a location for his ambulatory practice. 

Responsibtlty over time for patient care and 

professional services rendered there generally resides with the individual physician rather than 

an institution. 

A visit is a direct personal exchange between 

an ambulatory patient and a physician or a staff 

member working under the ph ysician’s supervision for the purpose of seeking care and 

rendering health services. 

A physician is a duly licensed doctor of medicine (M. D.) or doctor of osteopathy (D. O.) currently in practice who spends time in caring for 

ambulatory patients at an office location. Excluded from NAMCS are physicians who specialize in anesthesiology, pathology, radiology; 

physicians who are federally employed; physicians who treat only institutionalized patients; 

physicians employed fulI time by an institution; 

and physicians who spend no time seeing ambulatory patients. 

SYMBOLS 

Data not available 

Category not applicable—-–——------- . . . 

Quantity zero— — — 

Quantity more than Obut less than 0.05— 0.0 

Figure does not meet standards of 

* reliability or precision———————— 

Recent Issues of Advance Data 

No. 14.	 Weight by Height and Age of Adults 18-74 

Years in the United States in 1971-74 (Issued: 

November 30, 1977) 

No. 13.	 Ambulatory Medical Care Rendered in Pedlatricisns’ Offices in the United States, 1975 

(Issued: October 13, 1977) 

No. 12.	 Ambulatory Metilcal Care Rendered in Physicians’ Offices in the United States, 1975 

(Issued: October 12, 1977) 

From Vital and Health Statistics 

No. 11.	 Pregnant Workers in the United States (Issued: 

September 15, 1977) 

No. 10.	 Expected Size of Complete Family Among 

Currently Married Women 15-44 Years of Age 

in the United States in 1973 (Issued: August 

12, 1977) 

A complete list of Advance Data From the Vital and Health StatrMics is available from the Scientific and 

Technical Information Branch. 

GPO 925-326