Use of the Berg Balance Test to
Predict Falls in Elderly Persons
Background and Purpose. The purpose of this study was to determine
whether the Berg balance test could be used to predict an elderly
person's risk of falling. Subjects. Sixty-six residents of two independent
life-care communities, aged 69 to 94 years (X=79.2, SD=6.2), partic-
ipated. Methods. Subjects completed a questionnaire pertaining to
their fall history and activity level. The Berg balance test, consisting of
14 functional subtests, was then administered. Six months later,
subjects again completed the questionnaire. Results. Perfornlance of
activities of daily living predicted 43% of the subjects' scores. There was
a difference between the subjects who were prone to falling and those
who were not prone to falling, but the test demonstrated poor
sensitivity for predicting who would fall. The specificity of the test was
very strong. The use of an assistive device was a strong predictor of
perfor~nance on the Berg balance test. No relationship was noted
between increasing age and decreasing performance on the Berg
balance test. Conclusion and Discussion. Although the Berg balance
test demonstrated only 53% sensitivity, the results support the test
developers' use of 45 (out of 56) as a generalized cutoff score. Older
adults who scored higher than the cutoff score on the test were less
likely to fall than were those adults who scored below the cutoff score.
Decreased scores, however, did not predict increased frequency of
falls. Results must be viewed cautiously because self-report was the sole
Ineans of documenting fall history. [Bogle Thorbahn LD, Newton RA.
Use of the Berg balance test to predict falls in elderly persons. Phys
Key Words: Assessment, Balance, Geriatrics, Falls, Validity.
Linda D Bogle Thorbahn i
Roberta A Newton
Physical Therapy. Volume 76 . Number 6 .June 1996
ne in three persons over 65 years of age and
almost one in two persons over 80 years of
age will fall at least once each year.' This
incidence increases to 66% for ambulatory
residents of nursing homes.Wthough only 5% of all
falls result in serious injury, the psychological effects can
lead to impaired mobility, loss of function, and an
overall decrease in a person's quality of life.' Falls among
elderly persons have a multifactorial etiology, and con-
siderable research has been devoted to determining the
variables that correlate with the incidence and severity of
falls. Although no consistent relationship has been
found between a person's medical status, diagnosis, and
functional ability,4 most researcher^'.^ agree that the
characteristic most predictive of falling is a past history
of falls. Several nei~rologic and musculoskeletal factors
such as decreased ankle dorsiflexion strength, reduced
sensation, and increased reaction time contribute to
po~tural instability and fall^.^.^ Tinetti and Speechleyr)
identified three factors that correlate highly with falling
in community-dwelling and institutionalized elderly per-
sons: lower-extremity disabilities, foot problems, and gait
and balance abnormalities.
Impaired balance has been correlated with an increased
risk for hlls and a resulting increase in the mortality rate
of elderly persons who are prone to falling compared
with those who are not prone to falling.",Iu A reliable and
valid clinical measure for balance abilities increases the
physical therapist's ability to predict who is at risk for
falls. In our study, validity was assessed by examining
sensitivity and specificity. A test is determined to be
sensitive if it accurately identifies persons who should
have a positive test result; specificity indicates how
efficiently a test identifies those persons who should have
a negative result.'
Several researchers1"14 have measured balance abilities
following externally generated perturbations by using a
force platform. Research performed on elderly personsI5
indicates that sway increases with increased age. Over-
stall et all%noted, however, that sway did not differenti-
ate between people who were not prone to falling and
people who tripped but that sway was increased in
people who fell because they lost their balance.
Hu and Wo~llacott~~.'~
in postural stability and decreases in electromyographic
response time following a training program with a
balance platform. Berg et allg found that speed of sway,
which is thought to measure the amount of postural
adjustment necessary to maintain a neutral position, was
not sensitive enough to differentiate between people
based on assistive-device use. A faster speed of sway is
assumed to identify a person with greater difficulty
balancing. No correlation between increased sway ampli-
tude and frequency of falls has been doc~lrnented.~.l3
have documented improvements
Several studies have been conducted on the sensory
organization balance test (SOT) .X.2u-2y This test is
designed to assess balance abilities during six co~iditions
of altered vision and altered support surface (dense
foam). Di Fabio and Badke" reported interrater agree-
ment ranging from 68% to 100% for items on the SOT.
1.1) Bog-le Thorhiihn, PT, NCS, is Program Coordini~tor of Neuroscience, Department of Physical Tlleriipy. Bryn M;IWI- Ke11at)iliration Hospital,
414 Paoli Pike, PO Box 3005, Mal\.ern, PA 19355 (I~'S.4).
This st~tdy was completed in partiill fulfillment of Ms Hogle Thorh;thn's
Adv;~ncetl Master's 1)egl.e~ ;I[ Temple University.
KA Newton, Phn, YI', is Professor in Physic;il Therapy, (:allege of Allit:d Health, Ternple University. N Broi~d St, Philadelphii~, PA 19140.
The s~rldy protocol was ;~pprovetl hy the institution;ll review hoi~rds of Tcrnple University and B~yn Miiwr Rehahi1il;ititrn Hospital.
Physical Therapy . Volume 76 . Number 6 . June 1996
Bogle Thorbahn and Newton . 577
Anacker and Di FabiqZs in a study of elderly persons
with a recent history of falling, concluded that there was
a reduction in stance duration when the subjects stood
on a compliant surface as compared with when they
stood on a firm surface. There is some doubt, however,
as to whether this test is sensitive enough to enable
clinicians to predict who is at risk for fallsz4
Another test, the postural stress test, was developed for
use with elderly people.y5-" Interrater reliability esti-
mates for this test have ranged from .83 (intraclass
correlation coefficient [ICC]) to .99 (Cronbach's
Three tests assess functional abilities and balance (ie,
tests described by Tinetti,4 Mathias et a1,2H and Berg et
alz'). Tinetti4 reported 85% agreement on test items
when the test items were simultaneously scored by two
raters. It is difficult to compare Tinetti's interrater
reliability finding with those of other authors because
she did not use nonparametric statistical analysis for her
ordinal data. Tinetti et all also found that the risk of
falling increases linearly with the number of risk factors
Mathias et aPfl reported interrater agreement of W=.85
(Kendall coefficient of concordance test) when elderly
subjects were tested by physical therapists and W=.69
when elderly subjects were tested by senior physicians.
Mathias and colleagues' "get up and go" test has been
compared with several other balance assessments, but a
relationship between the test results and risk of falling
has not been determined.'".':'
For the test described by Berg et al,yY interrater reliability
was reported as .98 (ICC). To address validity, Berg et a16
determined that the balance score obtained on the test
correlated with a global rating of balance made by the
treating therapist (r= .81). The balance test also corre-
lated with platform-based measures of postural sway.
Both spontaneous sway (r=.55) and sway in response to
pseudorandom perturbations (r=.38) were assessed.
Validity of the balance test has been demonstrated by
determining that any subject scoring in the impaired
range on the assessment is 2.7 times more likely to
experience multiple falls as compared with subjects not
scoring in the impaired range." The Berg balance test
also was used to differentiate between subjects based on
their use of assistive devices. The Berg balance test scores
of those people who used a walker or a cane indoors
were different from each other and lower than than
those of individuals who used a cane outdoors only or
who walked without an assistive device. The Berg balance
test has also been shown to correlate with both the
Tinetti mobility index (r= .91) and the "get up and go"
test (r= -.76). That is, a person who scores low on the
completion) on the "get up and go" test.
We chose to study the Berg balance test because it takes
approximately 20 minutes to complete and requires no
sophisticated equipment, making it useful in clinical
settings. Measurements obtained with this test have
demonstrated excellent interrater reliability and a ten-
dency toward at least moderately strong concurrent
The purpose of our study was to determine whether the
Berg balance test would demonstrate sensitivity and
specificity'' in a population of elderly persons residing
in life-care communities. Each life-care community pro-
vided its residents with three different levels of care:
independent living, assisted living or personal care, and
skilled nursing. The research questions were: (1) Is the
Berg balance test predictive of current and future risk
for falls in elderly persons residing in life-care commu-
nities, as measured by self-report on a questionnaire, and
(2) Do balance score results achieved on the Berg
balance test correlate with the individual's self-perceived
activity level and overall balance ability? A fall was
defined as unexpected contact of any part of the body
with the ground. Near-falls were not included in our
analysis because they are more difficult to define, less
memorable, and less consequential.
A sample of convenience was used. Any independent-
living resident in two life-care communities who volun-
teered was tested. Seventy-one subjects were initially
tested, and only the 5 persons who were unable to follow
the directions for the test after three repetitions were
excluded. No subject was excluded on the basis of age,
gender, or disability. The remaining group of 16 men
and 50 women had a mean age of 79.2 years (SD=6.2,
range = 69 -94).
The equipment used for the Berg balance test was a step
stool, a mat table, a chair with arms, a tape measure, a
stopwatch, a pen, and a table. The balance assessment
consists of 14 subtests performed in a standard order
(Tab. 1). Each task is scored on a five-point scale (0-4)
according to the quality of the performance or the time
taken to complete the task, as ranked by the test devel-
opers. The maximum score for this assessment is 56.
Based on clinical experience, Berg et a16 contend that
scores below 45 indicate that someone is impaired, with
an increased risk for falls.
578 . Bogle Thorbahn and Newton Physical Therapy . Volume 76 . Number 6 . June 1996
Berg Balance Test Subtests
Sitting to standing
Standing to sitting
Standing with eyes closed
Standing with feet together
Reaching forward with an
Retrieving object from floor
Turning to look behind
P\ocing alternate foot on stool
Standing with one foot in front of
the other foot
Standing on one foot
At least two raters out of a pool of six raters were used
each day the data were collected. All raters were physical
therapists with at least 1 year of experience in the
treatment of patients with neurologic disorders. The
raters were not given any formal instruction on test
administ:ration, but they were given the test instructions
and the descriptors for each test item, as written by and
obtained from the test developers, the day prior to the
balance clinic. They were given the opportunity to ask
questions of the first author (LDBT) prior to adminis-
tering the test.
The purpose of the study and the subject of confidenti-
ality were discussed with all volunteer subjects. Confiden-
tiality was maintained by using randomly assigned num-
bers on all questionnaires and scoring sheets. After
signing a consent form, the following demographic data
were collected for each subject: age, gender, and the
presence of any major orthopedic or ~leurologic diag-
noses. Each participant was given a packet containing a
questionnaire, a balance test score sheet, and an enve-
lope. Each person was asked to address an envelope that
was later used to mail the 6-month follow-up question-
naires. Each participant completed a modified Activity
Index questionnaire.^",^' Each subject was then ran-
domly assigned to one of the raters, who completed the
Berg balance test (Tab. 1). Every fourth subject, after a
brief rest, was asked to complete the test again with
another rater. Seventeen of the 71 subjects were
retested. These results were used to calculate interrater
A Spearman rho (r,), a nonparametric version of the
Pearson product-moment correlation coeff~cient, was
used to analyze interrater reliability because the scores of
the Berg balance test are ordinal or ranked data. The
scores obtained from the 17 subjects who were tested
twice by two different raters were compared (r,=.88).
A letter was sent to all participants 3 months after
completion of the initial balance tests thanking them for
their participation and reminding them that a follow-up
questionnaire would be forthcoming. Six months after
the initial balance tests, the same questionnaire used
prior to the tests was sent to the participants with an
addressed and stamped envelope. The returned ques-
tionnaires were used to assess the predictive validity of
the balance assessment.
To answer the first research question, the relationship
between each subject's balance score and his or her
reported frequency of falls was analyzed by a chi-square
test. A Yates correction was not used because 2 degrees
of freedom was used in the computation, the signifi-
cance of the relationship was not borderline, and the
correction itself tends to be overly c~nservative.~~~~~
To answer the second research question, a multiple-
regression analysis was run to determine how each factor
(ie, age, gender, activity level, frequency of falls, self-
perception of balance, and use of an assistive device)
contributes to the composite score achieved on the
balance test. A chi-square test also was used to determine
whether the score on the Berg balance test successfully
differentiated among subjects based on their use of an
ambulatoiy assistive device. The original and 6-month
follow-up questionnaires were compared to determine
whether any major changes had occurred in the sample
under study. Any changes were to be reported.
Activity level was analyzed using information obtained
from the questionnaire on the amount of participation
in regular exercise. Exercise levels were given a rank
score of 0 to 8. A higher number corresponded to
increased frequency of participation in at least one of
three levels of activity: vigorous sports activity, light
physical activity, and social and recreational programs. A
limitation of this rating system was that the scale did not
allow for differentiation between subjects who frequently
participated in one type of activity and subjects who
infrequently participated in multiple levels of activity.
For the four questions regarding performance of activi-
ties of daily living (ADLs), each subject was given a rank
score of 0 to 6. The score given depended on how much
assistance the subject reported needing to complete
daily tasks such as cooking, cleaning, shopping, and
obtaining transportation. Subjects who scored higher on
the scale reported needing less assistance than those
who scored lower.
Physical Therapy . Volume 76 . Number 6 . June 1996
Bogle Thorbahn and Newton . 579
Assistive Device Use as Reported on Questionnaire
When Used No. of Subjects
Outside or for long distances
All the time
Number of Subjects Reporting Falls
1 - 2 falls
Twenty-five out of 66 subjects (38%) reported some type
of neurologic or orthopedic impairment. The four most
common orthopedic diagnoses reported were arthritis
(n=4), hip arthroplasty (n=2). status postlaminectomy
(n=2), and fractured vertebrae (n=2). The two most
common neurologic diagnoses reported were stroke
(n=6) and Parkinson's disease (n=5). Fifty-two percent
of the subjects rated their own balance as good or
excellent, and 86% of the participants felt that their
overall health was good or excellent. Seventy-five per-
cent of the subjects reported not using an assistive device
(Tab. 2), and most subjects did not report experiencing
any falls either initially (83%) or 6 months after taking
the Berg balance test (80%) (Tab. 3).
Eighty-five percent of the Gmonth follow-up question-
naires were returned. The comparison of number of falls
reported by the subjects on the initial questionnaire and
Comparison of Berg Balance Test Scores and Initial Frequency of Falls"
their performance on the Berg balance test is shown in
Table 4. When the information was compressed into a
2x2 chi-square table (Tab. 5), a relationship was found
between the actual values and the expected frequencies.
The sensitivity of the Berg balance test as compared with
the initial fall frequency was 53% (9/17), whereas the
specificity of the measure was 96% (46/48). When the
scores achieved on the Berg balance test were applied to
the 6-month follow-up fall frequency, the sensitivity
remained at 53% (8/15) and the specificity was 92%
The multiple regression indicated that performance
of ADLs predicted 43% of the total score achieved on
the Berg balance test (P<.001). Age accounted for
an additional 5% of the total score achieved (P<.02).
Table 6 shows the numbers of subjects who scored above
the cutoff score of 45, separated by age in decades.
There was no relationship between scores achieved on
the balance test and each subject's self-perception of his
or her balance abilities.
Scores on the Berg balance test also were examined in
relation to the use of assistive devices (Tab. 7). For the
purpose of the chi-square test, the three groups were
compressed into two groups: assistive device used and no
assistive device used. The chi-square test (Tab. 8) indi-
cated that a relationship existed (P<.001) between the
use of an assistive device and the score on the Berg
balance test. The sensitivity of the Berg balance test for
predicting use of an assistive device was 76% (13/17),
whereas the specificity was 94% (45/48).
Using the test developers' cutoff score of 45 (out of 56)
as a guideline, the Berg balance test is designed to
identify those individuals who are classified as "fallers"
(those who score below 45) and those individuals who
are classified as "nonfallers" (those who score 45 or
above). When analyzed with a chi-square test (Tab. 5),
Berg Balance Test Score
1 - 2 falls
l d (33.3)
8 (1 2.3)
2 (3.1) 3 (4.6) 1 2 ( 1 8.5) 48 (73.8) 65 (1 00.0)
" Pcrcent;~gc. ullown in pare~~theses.
"Suhject 1l;lcl arthritis arid used a walkel- r~~ll-ti~~~c.
' S111,ject had sevrl c. Parkinsolr's dirdsc and enlployed ; 1 fi~ll-time liw-i~~
"S~~hject rrpol.tcil severely impaired visio~~.
580. Bogle Thorbahn and Newton
Physical Therapy . Volume 76 . Number 6 . June 1996
Chi-Square Test Results for Comparison of Number of Falls Reported
on Initial Questionnaire and Performance on Berg Balance Testa
"Expected freqnencies shown ill parentheses. Subjects with impail-ments
.;cored bell~w 4.5 on the Berg balance test; subjects with0111 impairments scored
45 I>r ;~bovr on the Berg bal;~~~ce lest.
Performance on Berg Balance Test as Analyzed by Ages in Decades
(N = 66)
8 (1 3.9)
our two groups demonstrated a difference that would
not occur by chance. In addition, the Berg balance test
was demonstrated to be highly specific (96%). For
clinicians, this finding indicates that those persons who
score 4 5 1 and above on this assessment have a high
probability of not falling. The sensitivity of the Berg
balance test was low (53%). We attributed this result to
a variety of factors. We agree with TideiksaarI0 and
Studenski et a1,:44 who commented on the unclear rela-
tionship between risk of falls and physical impairments.
The subjects who fell most frequently were those who
scored closer to the cutoff score (Tab. 4), not further
away. A few of the subjects who scored in the most
impaired range on the balance test appeared to adopt
strategies for minimizing their risk of falling (eg, use of
companions and assistive devices). This finding empha-
sizes the difference between risk of falling and the
presence of some physical impairments. Subjects who
were the most physically impaired (limited in either
ability to ambulate or ability to transfer) did not have the
highest risk for falling because of their use of external
Our data provide evidence that falls are primarily
nlultifactorial in nature.l.Io A complete assessment of
risk of falling also must examine the environment in
which a person functions, not just a score achieved on
this or any other balance assessment. Studenski et al,''5
using a home evaluation tool, determined that the risk of
falling, ;is identified by defined hazards, increased when
the number of hazards increased. Modification of the
environment may reduce the frequency of falls.' A home
evaluation, such as that developed by Chandler et al,3f1
could be used in conjunction with the Berg balance test
to provide a clearer picture of the client's functional risk
Our research did not agree with the test developer^'"^^^'
determination that the Berg balance test is sensitive in
identifying fallers but did provide support for the claim
of specificity to identify individuals in the nonfaller
category. The Berg balance test demonstrated a moder-
ately str'ong ability to predict a person's use of an assistive
device (Tab. 8).
A linear relationship between increased frequency of
Subjects Age (Y)
Effect of Use of Assistive Device on Performance on the Berg Balance
Berg Balance Test Score (Frequency)
<20 21-30 31-45 >45 Total
Do not use an
Use an assistive
and for long
Use an assistive
device all the
4 45 49
3 5 10
Chi-Square Test Results for Assistive Device Use and Performance on
Berg Balance Testa
4 (1 2.6)
1 3 (4.1 ]
3 (1 1.4)
"Expected fiequenciea shown in parentheses. S~rhjecta with inrpairn~r~~ts
scored below 46 on the Brl-g balance test; sltbjects without imp;lirnie~lw sro~.rd
45 or ahwe on thr Berg balance Lest.
falls, either initially or at follow-up, and decreased scores
on the Berg balance test was not established. Increasing
age also did not correlate with decreasing balance ability
in our study. In this respect, we disagree with some
authors:i7 and agree with others.:iH Additional research is
needed to determine the effect aging has on an individ-
ual's balance ability. The reason for the disagreement
among researchers may be due to the different nature of
the groups of subjects ~tudied.:'~
Activity level did not appear to contribute to perfor-
mance on the Berg balance test, as determined by
multiple-regression analysis. This finding may in part be
due to the way activity level was measured. A standard-
ized index3(' was used, with some modification^,^^ as a
questionnaire. The scoring system, however, may not
Physical Therapy . Volume 76 . Number 6 . June 1996
Bogle Thorbahn and Newton . 58 1
have been sensitive enough to the variations in individ-
ual activity patterns. This hypothesis is supported by the
contribution ADL performance (43%) made to the
composite scores achieved on the Berg balance test. It
could be argued that those individuals who are capable
of performing the daily activities of cooking, cleaning,
shopping, and obtaining transportation are more active.
More research is needed in this area to determine the
contribution that activity level makes to overall balance
Our interrater reliability (,r;=.88) is lower than the
reliability determined by
. ' V e used a nonparametric test to deter-
mine interrater reliability because of what we considered
to be the ordinal nature of the scale used in the Berg
balance test. Raters disagreed the most on three items:
reaching forward with an outstretched arm, standing
with one foot in front of the other foot, and standing on
one foot. These are the most difficult of the subtests for
the subjects to perform. A determination of why the
raters disagreed the most on these items is beyond the
scope of this article, but a careful reading of the descrip-
tors for each test item is recommended prior to using
the test developers
Seventy-three percent of the subjects scored above the
cutoff score of 45, and 11 % of the subjects achieved a
perfect score of 56. There may be a ceiling effect to the
Berg balance test, making it insensitive to differences
among persons with very high levels of balance ability.
These individuals, however, are probably those who
would not require physical therapy for balance
Although problems have been noted with the self-report
method of collecting data on f a l l ~ , I - ~ ~
control for this limitation by assigning each subject a
random number and sending a reminder halfway
through the follow-up period. By doing so, we hoped to
increase the honesty of responses as well as improve the
recall of fall frequency.
we attempted to
Additional research is needed on individuals who score
between 31 and 45 on the balance test. Fifty-five percent
(6/11) of those individuals who fell scored in this
category (Tab. 4). Further analysis of this group also may
lead to improved sensitivity of the instrument. We
hypothesize that this group engaged in more risk-taking
activities and did not use external supports to compen-
sate for their deficits as compared with the group who
scored in the most impaired range. Additional research
is needed to answer this question and to examine
whether environmental factors contributed to this
group's higher risk of falling compared with the group
who scored lower on the balance assessment.
582 . Bogle Thorbahn and Newton
A more refined weighing system also is needed to
discriminate between levels of activity. This weighing
system is necessary to determine whether participating
in a rigorous exercise program is more beneficial than
simply maintaining an active lifestyle.
The Berg balance test continues to show strong interra-
ter reliability (,r,=.88) when raters are provided with
written instructions and are allowed to ask questions
prior to administering the balance test. Measurements
obtained with the Berg balance test show high specificity
but poor sensitivity for identifying people with increased
risk of falling. Improved sensitivity of the instrument is
needed, particularly for those older adults scoring closer
to the cutoff score of 45. The Berg balance test, however,
shows sensitivity and specificity to predict use of assistive
devices in the older adult. The Berg balance test is easy
to administer and requires no special equipment. U7e
believe that the determination of patients' risk of falling
may be substantially improved by also examining their
environment and how well they complete their activities
of' daily living.
We thank the residents of The Quadrangle, Haverford,
Pa, and W%ite Horse Village, Newtown Square, Pa, for
their dedication, without which this study would not
have been possible. We also thank Dean Paulson and the
staff at Bryn Mawr Rehabilitation Hospital for their
invaluable assistance and support.
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(Invited Commentary follows on page 584.)
Physical Therapy . Volume 76 . Number 6 . June 1996
Bogle Thorbahn and Newton . 583