Technical keport Documentation Page 

1. Report No. 2. Government Accession No. 3. Recipient's Catalog No. 

FAA-AM-75-4 

4. Title and Subtitle 5. Report Date 

THE USE OF VESTIBULAR TESTS IN CIVIL AVIATION MEDICAL 

EXAMINATIONS : SURVEY OF PRACTICES AND PROPOSALS BY 6. Performing Organization Code 

AVIATION MEDICAL EXAMINERS 

8. Performing Organization Report No. 

7. Author Is) William E. Collins, Ph. D.' Amelia o. Lennon, 

M.A., and E. Jean Grimm, B.S. 9. Performing Organization Name and Address 10. Work Unit No. (TRAIS) 

FAA Civil Aeromedical Institute 

P.O. Box 25082 11. Contract or Grant No. 

Oklahoma City, Oklahoma 73125 

13. Type of Report and Period Covered 

12. Sponsoring Agency Name and Address 

Office of Aviation Medicine OAM Report 

Federal Aviation Administration 

800 Independence Avenue, s .w. 14. Sponsoring Agency Code 

Washington, D.C. 20591 

15. Supplementary Notes 

This research was conducted under Tasks AM-A-73-PSY-33, AM-D-74-PSY-33, and 

AM-D-75-PSY-33. 

16. Abstract 

A brief, voluntary questionnaire was administered to 1,115 Aviation Medical 

Examiners (AME) to assess the frequency with which vestibular tests (broadly 

defined) were given during physical examinations of pilots, which tests were 

used, why they were used, whether AMEs believed that specific tests should be 

routine, and why they believed so. Responses were obtained from 55 percent of 

the AMEs (many not responding were new AMEs with no experience). Of the respondents, 58 percent routinely gave tests of balance,equilibrium, or vestibular 

functioning, 24 percent gave the tests under certain conditions, and 18 percent 

gave no tests. The Romberg and finger-pointing tests were the most frequently 

used and were employed most often for screening purposes or to identify a problem 

area. Seventy-five percent of the AMEs indicated that specific tests should be 

routine; the test most frequently recommended was the Romberg. The authors 

expressed the views that (a) any introduction of specific tests of vestibular 

function or equilibrium should be based in the overall medical value of the 

tests (not in an effort to significantly reduce disorientation-related general 

aviation fatalities by seeking to identify the disorientation prone, since most 

such accidents appear to be related to normal functioning of the vestibular 

system), (b) the tests should be simple, and (c) relatively brief modifications 

of the FAA Office of Aviation Medicine's "Guide for Aviation Medical Examiners" 

could be the vehicle for describing specific procedures and for generally improving 

standardization of the physical examination. Some possible modifications were 

proposed. 

17. Key Words 18. Distribution Statement 

Aviation Medicine Document is available to the public through 

Vestibular the National Technical Information Service, 

Testing Procedures Springfield, Virginia 22151 

19. Security Classif. (of this report) 20. Security Classif. (of this page) 21. No. of P oges 22. Price 

$3.00 PC 

Unclassified Unclassified $ .95 MF 

Form DOT F 1700.7 (8-72) Reproduction of completed page outhori zed 

THE USE OF VESTIBULAR TESTS IN CIVIL AVIATION MEDICAL. 

EXAMINATIONS: SURVEY OF PRACTICES AND PROPOSALS 

BY AVIATION MEDICAL EXAMINERS 

I. Introduction. 

The most recent annual review of aircraft 

accident data (1972) attributes over 15 percent 

of 681 fatal general aviation accidents to spatial 

disorientation.1 Aviation Medical Examiners 

(AME) are aware of the importance of the vestibuar system in the genesis of disorientation 

problems in flight, and, although there is no 

medical requirement for a specified test of vestibular function or spatial orientation in the certification of either general aviation or commercial 

pilots, many AMEs conduct such tests during 

flight physicals in completing the neurologic portion of the medical examination. Since vestibular 

involvement is traditionally associated with disorientation problems in aviation2 3 and since a 

substantial number of fatal accidents are attributed to this cause, the question of whether a 

specific vestibular test requirement is needed in 

pilot physicals has been posed intermittently in 

aviation medical circles. Thus, it seemed reasonable to assess in a uniform way the perceived 

needs for medical testing of vestibular function, 

the perceived value of existing tests, and the 

climate for possible introduction of a specific test 

requirement. The present survey, then, was undertaken to determine the extent to which vestibular testing (broadly defined) is done by 

AMEs, which tests are used, which tests are most 

highly recommended, what significance is attached to the tests, what actions are taken if 

tests are failed, and whether the AMEs believe 

specific tests should be given routinely. 

II. Method. 

A brief questionnaire was devised requesting 

one or more responses to four major items: 

1 

(1) In giving physical exams to pilots, do 

you routinely give any test of balance, equilibrium, or vestibular function? 

(NOTE : None is specified on the FAA examination form.) 

__ Yes __ No 

(2) If the answer to the above is "No": 

(a) In giving physical exams to pilots, 

do you ever give any tests of balance, equilibrium, or vestibular function? 

__ Yes __ No 

(b) If "Yes," under what conditions? 

(3) If the answer to either of theoabove questions if "Yes": 

(a) What tests do you give? 

(b) What significance do you attach to 

these tests ? 

(c) What action do you take if a pilot 

performs poorly on these tests? 

( 4) Do you think tests of balance, equilibrium, or vestibular function should be given 

routinely in evaluating suitability for flying 

status? __ Yes __ No 

If "Yes," which ones and why? If "No," 

why not? 

The subject pool comprised a total of 1,115 

AMEs who attended FAA-sponsored AME seminars during 1972-1974 in Chicago, New Orleans, 

Oklahoma City, San Francisco, and Washington, 

D.C. Responses to the voluntary questionnaire 

were elicited from 618 of the attendees, or approximately 55 percent (see Table 1). (Many 

not responding were new AMEs with no experience.) Respondees were divided by specialty 
TABLE 1. The Number of Physicians, by Specialty, Who Responded to the AME Questionnaire at Each cf Six AME Seminars 

AME Seminars 

Medical Chicago I Chicago II New Orleans Oklahoma City San Francisco Washington, D.C. Total 

Specialties (221 attendees) (132 attendees) (197 attendees) (89 attendees) (301 attendees) (175 attendees) (1,115) 

General Practice 75 52 61 

Internal Medicine 12 14 

Surgery 12 8 

Miscellaneous 

Otology 

Ophthalmology 4 4 

Aerospace Medicine 4 

Industrial Medicine 4 0 

Neurology-Psychiatry .......!! _! .......!! 

Number Responding 119 Sit 97 

1o Reapond ing 53. 97. 63.6% 49.2% 

into nine catgories (Table 1), with the following 

number of responding physicians in each category : general practice, 349 ; internal medicine, 

87; general surgery, 62; otolaryngology, 21 ; 

ophthalmology, 18; aviation medicine, 14; industrial medicine, 9 ; psychiatry, 6; and miscellaneous, 52. 

The straightforward "Yes-No" answers to the 

questionnaire were tallied by specialties. The 

responses to open-ended questions were examined 

by two raters; empirical categories were established and each response was assigned to the 

most suitable category. 

III. Results. 

A. Who Gives Tests.? Of the 618 AMEs responding, approximately 58 · percent reported 

that they gave tests of balance, equilibrium, or 

vestibular functioning routinely during physical 

examinations o£ pilots, 24 percent reported that 

they administered the tests under certain conditions (yielding a total of 82 percent who gave 

tests on some if not all occasions), while 18 percent reported that they never gave such tests (see 

Table 2). Statistical analyses, by physicians' 

specialties, yielded a significant overall X 2 

(16.604, p<.05) between the proportions of 

physicians who never gave tests and the proportions of those who gave tests routinely or under 

certain conditions, thereby demonstrating a significant relationship between responses and 

2 

44 71 46 349 

29 16 87 

11 15 62 

16 52 

21 

18 

2 14 

0 

.......!! _3 _2 _6 

80 136 102 618 

89.9% 45.2% 58.3% 55.4% 

specialties. Individual chi square tests were performed between all possible pairings of these 

proportions by physician categories. It was 

found that the responses of the physicians specializing in internal medicine differed significantly from those of general practitioners and 

surgeons (p<.05) and from those of ophthalmologists and otolaryngologists (p < .01). In 

addition, the responses of physicians specializing 

in aviation medicine differed significantly from 

those of surgeons, ophthalmologists, and otolaryngologists (p<.05). These differences can be 

interpreted to show that, in general, specialists in 

internal medicine and aviation medicine tend to 

give vestibular tests more often than most 

physicians in other specialties. 

Those physicians who reported they did not 

give tests routinely but did give them under certain conditions were asked to define those conditions. An overwhelming majority of the 146 

physicians responding to this question reported 

they performed some sort of specific vestibular 

test or tests if their suspicions were aroused in 

observing the patient (e.g., unusual gait) or if 

the patient's past history (e.g., dizzy spells) indicated a need for further testing. A few others 

responded that their use of the tests depended 

on the patient's age at the time of exam, if the 

patient had any specific complaints, or if he was 

applying for a certificate for the first time. 
TABLE 2, Summary, by Medical Specialty, of AMEs Who Give Vestibular Tests Routinely, 

Under Special Conditions, or Not At All 

Medical Specialties 

NEURO/ 

Item GP IM SURG MISC 

Give tests N 209 55 29 31 

routinely 

% 59,9 63,2 46,8 59,6 

Give tests N 73 24 19 12 

under certain 

conditions % ~ ~ ~ 23,1 

Total who N 282 79 48 43 

give tests 

routinely or % 80.8 90.8 77.4 82,7 

unier certaitl 

conditions 

Never give N 67 8 14 9 

tests 

% 19,2 9.2 22,6 17,3 

B. Which Tests Are Used.'! In identifying the 

tests that they used, 70 percent of the 506 AMEs 

who gave tests some or all of the time responded 

with more than one answer. The test cited most 

often (by 81 percent of those who gave tests) 

was the Romberg (standing upright with feet 

together and eyes closed), which was identified 

by either name or description. Tests involving 

finger-pointing were named by 36 percent of the 

respondents, and two-thirds of them specifically 

listed the finger-to-nose test. General tests, such 

as observation of gait and equilibrium, and 

agility of movements, were listed by 16 percent 

of the physicians. Tests for spontaneous nystagmus were mentioned by 16 percent of the 

physicians, and an additional 5 percent of the 

responses cited some other sort of observation of 

eye movements, such as the corneal reflex. Other 

tests listed were standing on one leg with eyes 

closed (12 percent), heel-to-toe walking (8 percent), and caloric irrigation ( 8 percent). Named 

less frequently were neurologic and central nervous system exams, tests involving quick changes 

of position and turning, and tests assessing arm 

and leg coordination. 

3 

OTO OPHrR AM IHD PSY TOTAL 

10 5 13 4 4 360 

47.6 27.8 92.9 50,0 66.7 58,3 

4 7 1 4 2 146 

..!&Q 38,9 ...Ll ~ 33.3 ~ 

14 12 14 8 6 506 

66,7 66.7 100,0 88,9 100.0 81,9 

7 6 1 112 

33.3 33,3 11,1 18,1 

C. Perceived Significance of Tests. The individual answers given by the AMEs concerning the significance they attached to the tests 

they gave were examined and divided into broad 

categories. Approximately 25 percent responded 

that the tests were used basically for screening 

purposes to identify a need for more extensive 

testing or consultation. About 19 percent believed that the tests' significance was to identify 

neurologic and/ or vestibular problems. Fourteen percent of the AMEs simply stated that 

the tests were very important and they placed 

much significance on the results; 7 percent said 

the tests were of little or no significance. Eight 

percent of the responses were noncommital answers, such as "depends on results," "suggestive," 

etc. Other diverse responses were noted. 

Since specific vestibular or equilibrium tests 

and procedures are not specified in examining 

pilots, it was of interest to note that if a pilot 

applicant performed poorly on the tests, 26 percent of the AMEs indicated they referred the 

pilot to an otologist or neurologist for further 

evaluation, 14 percent forwarded the results to 

the FAA, and 13 percent conducted further tests 
themselves (particularly neurologic). Ten percent specifically noted that it had never happened 

that an applicant performed poorly (not once 

in 9,000 exams, according to one general practitioner with 15 years of AM:E experience). Only 

2 percent admitted that they had failed a pilot 

who had performed poorly, and only 1 percent 

said that they had passed a pilot in spite of his 

poor performanee. Otner response statistics can 

be summarized as follows : 18 percent did not 

respond to the question since they reported they 

did not administer any tests, 9 percent gave 

various combinations of the responses noted 

above, 4 percent left the question blank, and 3 

percent responded that they repeated the test, 

advised the applicant, or made some sort of 

judgment on the applicant's abilities. 

D. Should Tests Be Routine.'! The final question asked if the physicians thought tests of 

balance, equilibrium, or vestibular function 

should be given routinely in evaluating suitability for flying status. Of the respondents, 75 

percent thought that tests should be given routinely and 25 percent said they did not believe 

in routine tests. "While statistical analyses, by 

medical specialties, yielded a nonsignificant overall X 2 value between the proportions of physicians who believed in giving tests and those who 

did not, a few of the individual paired comparisons showed some interesting relationships. 

The responses of the general practitioners were 

significantly different from those of the surgeons 

(p < .05), ophthalmologists (p < .05), and otolaryngologists (p<.01). "While about 77 percent 

of the general practitioners believed that tests 

should be given routinely, it is of interest to note 

that only 52 percent of the otolaryngologists 

recommended routine tests, the lowest percentage 

of all the specialties. 

In comparing answers to question 1 and question 4, some discrepancies appeared to exist 

between what is actually done by the physicians 

and what they recommended. Fifteen percent 

of all the respondents who do not routinely give 

vestibular tests stated that tests should be given 

routinely. A small percentage (less than 4 percent) did not believe that tests should be routine 

but did administer tests routinely. 

4 

Of those who believed that tests should be 

routine, almost hal£ ( 49 percent) recommended 

the Romberg test (by name or description). 

Nineteen percent listed tests involving fingerpointing, 12 percent mentioned tests involving 

eye movements, and 11 percent cited tests of 

balancing on one leg. Many listed more than 

one test to be given routinely. Other tests mentioned, but not so frequently, were observation 

of gait, heel-to-toe walking, caloric irrigation, 

quick position changes, leg and hand coordination, turning, and several others including tests 

using tuning forks. 

The AM:Es who recommended specific routine 

vestibular tests were also asked why they recommended the tests, and the AM:Es who indicated 

that they did not believe in routine tests were 

asked to explain why they did not recommend 

them. Of those who recommended that specific 

vestibular tests be given routinely, 58 percent 

gave no further explanation (possibly feeling 

that their response to a previous question provided adequate reason), 18 percent recommended 

using tests routinely in order to identify abnormalities, 10 percent stated that if tests were 

given routinely they should be kept simple and 

short (such as the Romberg), 5 percent indicated 

that passing the tests was necessary for safety 

in flight, and 9 percent gave a variety of other 

responses. 

Of the AM:Es who did not think tests should 

be given routinely, 28 percent did not give any 

reasons, 23 percent responded that none of the 

tests with which they were familiar seemed adequate, 15 percent believed that tests should be 

given only if a specific problem was noted that 

would require further investigation, 16 percent 

believed the tests were unnecessary because abnormalities would probably be discovered either 

during other parts of the physical exam (e.g., 

history-taking) or by the flight examiner, and 

7 percent responded that although the tests might 

be worthwhile, they would take up too much 

time and, therefore, were not practical; the remaining 11 percent of responses were classified as 

miscellaneous. 
About 10 percent of the AMEs had ambivalent 

feelings about giving vestibular tests routinely. 

Although these physicians did not give a "Yes" 

or "No" response to the item suggesting routine 

tests, they commented that they were unsure of 

the practical application of available tests to 

flying and did not believe that vestibular tests 

would lead to any significant information. 

IV. Discussion. 

These results indicate that a majority of 

AMEs routinely perform some type of vestibular 

test (broadly defined) primarily to assess the 

possibility of a need for further medical evaluation. Other AMEs conduct specific tests in 

special circumstances; i.e., if the examinee's history or his performance on another part of the 

physical exam suggests some vestibular involvement. Most often the Romberg test is used. 

A clear majority of the AMEs (75 percent) 

would be receptive to a requirement for specific 

vestibular tests. Based both on the tests most 

frequently used in the absence of such a requirement and on some of the physicians' comments, 

it is apparent that any required tests must be 

kept simple. However, only a bare majority of 

the AMEs with specialties in otolaryngology 

were in favor of routine testing. Many of those 

who did not favor formal test requirements emphasized the usefulness of a carefully obtained 

history and felt that tests not already routine 

should be given only if warranted by the history. 

It is perhaps surprising at first that specific 

tests (such as the Romberg) are not routinely 

performed by all AMEs in completing the neurologic part of the medical examination (item 46 

on FAA Form 8500-8. The reason for this omission may well relate to the procedures and material presented in the FAA Office of Aviation 

Medicine's "Guide for Aviation Medical Examiners." For example, the listed neurologic conditions for which medical certificates will be 

denied or deferred are all of a type that is 

ascertained in history-taking (e.g., epilepsy, 

brain surgery, unexplained disturbance of consciousness, etc.) ; most other conditions for denial 

or deferral serve to specify some observation (or 

test) by the medical examiner (e.g., perforation 

of eardrum, pulse rate, cardiac arrhythmia, 

5 

anemia, emphysema, nonreactive pupils, sinus 

tumors, etc.) Moreover, the guide does not 

specify examination procedures for neurologic 

(or vestibular) testing, although it gives detailed 

procedures for other examinations (such as eye 

and ear). Thus, many AMEs may feel that they 

have complied with item 46 on the examination 

form by a careful history-taking covering those 

specified conditions which would result in denial 

or deferral, or perhaps by a general observational 

impression of the applicant. 

V. Conclusions. 

Although disorientation is a significant cause 

of fatal accidents in general aviation, it is clear 

that most of its manifestations are due (a) to 

the normal, rather than abnormal, functioning 

of the vestibular system in motion environments 

and (b) to a lack of visual information about 

objects fixed relative to Earth.2 4 While clearly 

unhealthy vestibular or equilibrium systems 

could conceivably increase the likelihood or severity of disruptive (and dangerous) orientation 

experiences in flight, the majority of orientationrelated incidents and fatal accidents in general 

aviation are probably attributable to normal 

vestibular functioning coupled with inadequate 

instrument flying skills and questionable judgment about safe flying conditions. 

Thus, in periodic reevaluations of FAA medical standards for pilots, any hypothesized need 

for a vestibular (or spatial orientation) test requirement should probably reflect the particular 

usefulness of that test as an indicator of medical 

disorders of significance to the health, well-being, 

and performance capabilities of the examinee 

rather than as an indicator of, say, "disorientation proneness." In this regard, it would be 

entirely feasible to introduce orientation test 

requirements and improve the uniformity and 

completeness of aviation medical examinations 

by simply modifying the "Guide for Aviation 

Medical Examiners." Modifications could be 

added to both the "Eyes, General" and the 

"Neurologic" portions of the examination (items 

31 and 46 on FAA Form 8500-8). Since the 

tests specified should be simple and should not 

result in many "false positives," the Romberg 

(standing with feet together, eyes closed, and 

arms fol_ded) or perhaps the sharpened Romberg 
(standing heel-to-toe with eyes closed and arms 

folded: sometimes referred to as Mann's test5 ) 

would seem to be an adequate, if minimal, choice 

(both are uniformly noted in clinical texts5 6 ) 

and would be readily accepted by AMEs; either 

test could be specified as a recommended part of 

the neurologic portion of the examination. In 

combination with an expanded description of 

existing visual requirements on the airman's 

medical exam (i.e., examinations for the presence 

of spontaneous nystagmus, to include fixation to 

the right, to the left, upward, and downward as 

well as in the primary position67 ), the Romberg 

or sharpened Romberg could formally provide 

general information regarding orientation function and improve the uniformity of required 

examination procedures. If a more definitive 

test is desired (and is in keeping with practical 

needs for a test that is simple and brief and 

can be readily performed in the AME's office), 

an examination for nystagmus following head 

movements would probably represent an appropriate selection ; this test has been cited as one 

of the best single indicators of a disturbance in 

the vestibular system, 8 but some expertise probably would be required for proper administration and interpretation. Positive findings on 

any of these tests should be used only to suggest 

more in-depth testing. Moreover, if the above 

suggestions (or other alternatives) ar.e ever implemented, they should be recommended in a 

context that would neither deemphasize the importance of obtaining a good history in regard 

to spatial orientation nor discourage practitioners from using supplementary (but not required) 

tests of orientation that they feel provide useful 

information to them in the practice of the medical arts. 

References 

1. National T·ransportation Safety Board: Annual Review of Aircraft Accident Data (U.S. General Aviation, Calendar Year 1972). Report No. NTSB-ARG74-3, 1974. 

2. Benson, A. J.: Spati·al Disorientation in Flight. In 

Gillies, J. A. (Ed.), A Textbook of Aviation Physiology, New York, Pergamon, 1965, 1086-1129. 

3. Waite, R. E., and M. R. DeLucchi: Labyrinthine and 

Proprioceptive Aspects of Aerospace Medicine. In 

Randel, H. W. (Ed.), Aerospace Medicine (2nd ed.), 

Baltimore, Williams and Wilkins, 1971, 254-267. 

4. Collins, W. E.: Effective Approaches to Disorientation Familiarizati:on for Aviation Personnel. FAA 

Office of Aviation Medicine Report No. 70-17, 1970. 

6 

5. Fischer, J. J.: The Labyrinth, New York, Greene and 

Stratton, 1956. 

6. Toglia, J. U.: Neurological Examination. In Spector, 

M. (Ed.), Dizziness and Vertigo (Diagnosis and 

Treatment), New York, Greene and Stratton, 1967, 

92-96. 

7. Proud, G. 0. : Spontaneous Nystagmus. In Spector, M. 

(Ed.), Dizziness and Vertigo (Diagnosis and Treatment), New York, Greene and Stratton, 1967, 48-50. 

8. Spector, M.: Positional Nystagmus. In Spector, M. 

(Ed.), Dizziness and Vertigo (Diagnosis and Treatment}, New York, Greene and Stratton, 1967, 50-52.