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CMAJ • AUG. 30, 2005; 173 (5) 489
© 2005 CMA Media Inc. or its licensors
Research
Recherche
F
railty is a term widely used to denote a multidimen-
sional syndrome of loss of reserves (energy, physical
ability, cognition, health) that gives rise to vulnera-
bility. It appears to be a valid construct, but how exactly to
define it remains unclear.
1–8
There are many operational
definitions,
1,5,9–13
which typically are rules-based; for exam-
ple, a person may be defined as frail if 3 or more symptoms
(of unintentional weight loss, feeling exhausted, weak grip
strength, slow walking speed and low physical activity) are
present.
5
Rules-based definitions often are derived from
multiple regression analyses and can be speciously precise,
for example in requiring combinations of factors that might
not apply to an individual case.
Summing the number of impairments is another way to
define frailty.
2
Despite its strong predictive validity,
2,14,15
this approach is time-consuming and not widely used clin-
ically. A third class of operational classifications, which in
this report we attempt to extend, relies on clinical judg-
ment to interpret the results of history-taking and clinical
examination.
16,17
The creation of so many scales to measure frailty reflects
uncertainty about the term and its components. The ability
to measure frailty is useful at a health care policy level as
well as clinically: Information about frailty helps program
planners by identifying the range of services that might be
required and the anticipated need for them. Clinically,
frailty stratification can help to plan interventions or to
predict a patient’s risk of death or need for institutional
care. Because the scales are intended to stratify risk, the
ability to predict adverse outcomes serves a common goal.
In the Canadian Study of Health and Aging (CSHA), we
have worked with 3 approaches. First, like other groups, we
developed a rules-based definition of frailty.
12
Later, we de-
veloped (and still actively work with) a method of counting
a patient’s clinical deficits (identified by means of signs,
symptoms and abnormal test results). This approach is re-
producible and correlates highly with mortality,
2
but in
clinical use the deficit count is unwieldy. In this paper, we
describe our third approach: the derivation and validation
of the Clinical Frailty Scale, a measure of frailty based on
clinical judgment.
Methods
The CSHA is a representative 5-year prospective cohort study.
Its first stage of investigation (CSHA-1) began in 1991 with
10 263 people aged 65 years and older, recruited with the aim of
describing the epidemiology of cognitive impairment and other
important health issues in elderly Canadians.
18–20
From the clinical
examinations we did within this cohort, we developed the rules-
based frailty definition
12
and the Frailty Index, a measure of frailty
obtained by counting various clinical deficits (Appendix 1). After-
ward, we also developed CSHA scales for function and overall
clinical frailty, with the goal of creating tools that could stratify
elderly patients as to their relative degree of vulnerability (i.e.,
A global clinical measure of fitness and frailty
in elderly people
Kenneth Rockwood, Xiaowei Song, Chris MacKnight, Howard Bergman, David B. Hogan,
Ian McDowell, Arnold Mitnitski
Abstract
Background: There is no single generally accepted clinical defini-
tion of frailty. Previously developed tools to assess frailty that
have been shown to be predictive of death or need for entry
into an institutional facility have not gained acceptance
among practising clinicians. We aimed to develop a tool that
would be both predictive and easy to use.
Methods: We developed the 7-point Clinical Frailty Scale and ap-
plied it and other established tools that measure frailty to 2305
elderly patients who participated in the second stage of the
Canadian Study of Health and Aging (CSHA). We followed
this cohort prospectively; after 5 years, we determined the
ability of the Clinical Frailty Scale to predict death or need for
institutional care, and correlated the results with those ob-
tained from other established tools.
Results: The CSHA Clinical Frailty Scale was highly correlated
(
r
= 0.80) with the Frailty Index. Each 1-category increment of
our scale significantly increased the medium-term risks of
death (21.2% within about 70 mo, 95% confidence interval
[CI] 12.5%–30.6%) and entry into an institution (23.9%, 95%
CI 8.8%–41.2%) in multivariable models that adjusted for age,
sex and education. Analyses of receiver operating character-
istic curves showed that our Clinical Frailty Scale performed
better than measures of cognition, function or comorbidity in
assessing risk for death (area under the curve 0.77 for 18-
month and 0.70 for 70-month mortality).
Interpretation: Frailty is a valid and clinically important construct
that is recognizable by physicians. Clinical judgments about
frailty can yield useful predictive information.
CMAJ
2005;173(5):489-95
DOI:10.1503/cmaj.050051
their risks of death and of entry into an institutional facility) with
simple clinical descriptors. We defined the Clinical Frailty Scale
using the terminology of Streiner and Norman.
21
Rooted in our
theoretical model of fitness and frailty
7
and the importance of
function (which we reported in earlier investigations),
12
our Clini-
cal Frailty Scale (Box 1) ranges from 1 (robust health) to 7 (com-
plete functional dependence on others).
In 1996, we began CSHA-2, the second stage of the study. Of
the 10 263 people in CSHA-1 who had been examined clinically
and found to be without dementia, 2305 (22.5%) were examined
again by one of a team of clinicians (33 family physicians, 30 in-
ternists or geriatricians, 11 neurologists and 3 psychiatrists), who
then applied the Clinical Frailty Scale and the other measures in
Box 2, for comparison. This reduced study population (874 men
[37.9%] and 1431 women) consisted of 210 people (9.1%) who
had entered institutional facilities since CSHA-1; 1326 (57.5%)
who were still living at home or elsewhere in the community and
whose 3MS screening results in CSHA-2 now indicated cognitive
impairment (i.e., a 3MS score of 77 or less); and 769 (33.4%), also
living within the community, whose 3MS scores remained at 78
or greater and who formed a comparison group.
Our objective in the present study (CSHA-3), begun in 2001,
was to validate the Clinical Frailty Scale by following those pa-
tients who remained alive 5 years after CSHA-2 (1299/2305
[56.4%]). Follow-up vital and domicile status (living in the com-
munity or in an institution) was known for all 2305 participants
who did not have dementia at the time of CSHA-2, of whom 249
had entered an institutional facility between CSHA-2 and -3.
At the end of the clinical interview in CSHA-2, the interview-
ing physician assigned the subject a score of 1 to 7 on the Clinical
Frailty Scale. Each interview was reviewed and scored again by a
multidisciplinary team that included the physician and therefore
was not blinded to the initial score.
Given the increased likelihood of falls, episodes of delirium
and cognitive impairment among people who are frail, we
recorded that information. Physicians making the initial Clinical
Frailty Scale assessment had access to diagnoses and assessments
related to these variables and other measures of comorbidity,
function and associated features that inform clinical judgments
about the severity of frailty. They were, however, unaware of sub-
jects’ results on other frailty indexes. The subjects assessed were
almost always new to the clinician involved.
To assess the construct validity of the CSHA Clinical Frailty
Scale, in the analysis we compared patients’ scores from the initial
assessments only with their results from other established tools
that indicate the degree of frailty by measuring function and co-
morbidity
1
(see Box 2).
12,23–26
When applying the CSHA Function
Scale, we excluded “walking” and “transferring” because data
from nursing homes were incomplete for many patients.
The Frailty Index is a count of 70 clinical deficits from the
CSHA clinical assessment (Appendix 1). Items included the pres-
ence and severity of current diseases, ability in the activities of
daily living, and physical and neurological signs from the clinical
examinations. Each deficit was dichotomized or trichotomized
and mapped to the interval 0–1 (i.e., individual assessment items
could be scored as 0, 0.33, 0.50, 0.67 or 1.0) to represent the
severity or frequency of the problem (see Box 2). No variable had
more than 5% missing data. Except for the Clinical Frailty Scale
(which was completed on all but 8 patients), any values that were
missing were imputed using the relevant mean.
We used Pearson or Spearman correlation coefficients to mea-
sure the degree of correlation (i.e., to test convergent construct
validity) between the Clinical Frailty Scale and the other, estab-
lished measurement tools. To assess predictive validity, an aspect
of criterion validation,
21
we constructed Kaplan–Meier curves per
Rockwood et al
490 JAMC • 30 AOÛT 2005; 173 (5)490 JAMC • 30 AOÛT 2005; 173 (5)
Box 1: The CSHA Clinical Frailty Scale
1
Very fit
— robust, active, energetic, well motivated and
fit; these people commonly exercise regularly and are in
the most fit group for their age
2
Well
— without active disease, but less fit than people in
category 1
3
Well, with treated comorbid disease
— disease symptoms
are well controlled compared with those in category 4
4
Apparently vulnerable
— although not frankly dependent,
these people commonly complain of being “slowed up”
or have disease symptoms
5
Mildly frail
— with limited dependence on others for
instrumental activities of daily living
6
Moderately frail
— help is needed with both instrumental
and non-instrumental activities of daily living
7
Severely frail
— completely dependent on others for the
activities of daily living, or terminally ill
Note: CSHA = Canadian Study of Health and Aging.
Box 2: Tools for measuring degree of frailty that were
compared with the CSHA Clinical Frailty Scale*
• Modified Mini-Mental State Examination
22
(3MS), in which
a score† of 77 or less indicates cognitive impairment
• Cumulative Illness Rating Scale,
23
a comorbidity measure that
has been validated with autopsies
• A history† of falls, delirium, cognitive impairment or dementia
(as per DSM-III-R criteria for the diagnosis of dementia)
24
• CSHA rules-based definition of frailty,
12
which categorizes
subjects as 0 (having no cognitive or functional impairment),
1 (isolated urinary incontinence), 2 (dependent in 1 ADL or
having a diagnosis of CIND) or 3 (dependent in at least 2 ADLs,
having mobility impairment or having a diagnosis of dementia)
• CSHA Frailty Index, a count of 70 deficits (listed in Appendix 1),
including the presence and severity of current diseases, ability
in ADLs and physical signs from clinical and neurologic exams.
(A person with 7 deficits, for example, would have an index
score of 7/70 = 0.10. The relative frailty or fitness of a patient
can be calculated as a percentage difference from the average
score for people of that age.) To indicate severity, each deficit
not restricted by its nature to two values (i.e., 0 or 1 for absence
or presence, respectively) was assigned three (0, 0.5 or 1) or four
values (0, 0.33, 0.67 or 1.0), as appropriate
• CSHA Function Scale (based on the extensively validated Older
American Resources Survey), which scores the patient on each
of 12 ADLs (some instrumental) as 0 (the patient is independent
in carrying out this ADL), 1 (needs assistance) or 2 (is incapable)
Note: CSHA = Canadian Study of Health and Aging, 3MS = Modified Mini-Mental State
Examination, ADL = activity of daily living, CIND = cognitive impairment, no dementia.
*Except for the 3MS, a higher score on these tests represents greater morbidity.
†The clinicians assessing study participants on the CHSA Clinical Frailty Scale were
aware of these factors in the medical history but blinded to scores from all the other
indexes listed, except for results from the 3MS (as indicated).
scale category. All significance tests were 2-sided; differences were
assessed for significance (p ≤ 0.05) with the log–rank test. In the
multivariable analyses, having first checked for proportionality,
we used Cox regression analyses to estimate hazard ratios and
construct 95% confidence intervals (CIs) independently for the
3MS score
22
and outcomes of the CSHA Clinical Frailty Scale,
and the Cumulative Illness Rating Scale,
23
as well as the CSHA’s
Function Scale, rules-based frailty definition
12,16
and Frailty Index,
2
adjusting each for age, sex and years of education. Receiver oper-
ating characteristic (ROC) curves
27
were calculated to estimate the
areas under the curves for relevant predictor variables in relation
to death and entrance into an institutional facility. An intraclass
correlation coefficient was used to assess interrater reliability be-
tween the 2 Clinical Frailty Scale ratings (i.e., the initial scorings
done by physicians and those done later by multidisciplinary
teams during CSHA-2).
The research ethics committees of each institution approved
the study, and all participants (or their designates) signed
informed-consent forms. CSHA funding was chiefly (> 95%) pub-
lic and from a variety of sources, as specified in the Acknowledge-
ments. Sponsors had no role in the selection of the objectives or
in the analysis, write-up or submission of this report.
Results
Participants with higher scores on the Clinical Frailty
Scale were older and more likely to be female, cognitively
impaired and incontinent; to have impaired mobility and
function: and to have more comorbid illnesses than those
with lower scores (Table 1). They also had higher scores
according to both the Frailty Index and the rules-based
frailty definition.
12,16
Of note, at the highest level of frailty
our participants had fewer falls, probably reflecting the
greater proportion who were bedridden. The degree of
correlation between the judgment-based CSHA Clinical
Frailty Scale and the mathematically derived Frailty Index
was high (Pearson coefficient 0.80, p < 0.01), confirming
construct validity. The Clinical Frailty Scale and the Frailty
Fitness and frailty in elderly people
CMAJ • AUG. 30, 2005; 173 (5) 491
Table 1: Distribution of frailty attributes by category of the Canadian Study of Health and Aging (CSHA) Clinical Frailty Scale*
12 3 4567
Characteristic
Very
fit
Well
Well, with treated
comorbid disease
Apparently
vulnerable
Mildly
frail
Moderately
frail
Severely
frail
Patients, no. 216 260 476 349 305 497 194
Age, mean (SD), yr 80.3 (5.9) 83.0 (6.8) 82.4 (6.3) 83.7 (6.2) 86.4 (6.5) 87.4 (6.7) 88.1 (7.1)
Education, mean (SD), grade 9.6 (4.1) 9.9 (4.2) 9.6 (4.1) 8.8 (3.7) 9.7 (4.1) 9.4 (3.9) 9.1 (3.9)
Women, % 51.8 58.5 57.1 56.2 64.6 68.6 80.4
No cognitive impairment, % 75.9 63.1 57.1 39.3 18.7 9.7 1.0
Cognitive impairment, no
dementia, % 20.4 29.2 34.9 45.6 39.7 21.5 5.8
Dementia, % 3.7 7.7 8.0 15.2 41.6 68.8 93.3
With falls, % 13.0 20.8 24.6 40.4 45.9 48.7 31.4
With urinary incontinence, % 8.3 12.3 17.2 26.6 31.8 60.4 92.8
With impaired mobility, % 0.5 0.8 5.2 18.3 37.7 57.9 63.4
Modified Mini-Mental State
Examination, mean score* (SD)
87.1 (9.9) 82.6 (13.9) 83.2 (12.7) 79.1 (13.3) 70.2 (17.7) 56.2 (22.2) 31.9 (21.0)
Cumulative Illness Rating Scale,
mean score (SD) 1.8 (1.9) 2.5 (2.3) 4.9 (2.8) 6.2 (3.1) 6.4 (3.9) 7.0 (4.0) 6.4 (4.7)
CSHA measurement tools
Rules-based frailty definition,
mean score (SD) 0.72 (1.01) 1.14 (1.08) 1.34 (1.08) 1.90 (0.95) 2.45 (0.71) 2.82 (0.40) 2.94 (0.23)
Frailty Index, mean score (SD) 0.09 (0.05) 0.12 (0.05) 0.16 (0.07) 0.22 (0.08) 0.27 (0.09) 0.36 (0.09) 0.43 (0.08)
Function Scale, mean score (SD) 0.05 (0.12) 0.11 (0.16) 0.15 (0.19) 0.27 (0.22) 0.45 (0.24) 0.71 (0.24) 0.87 (0.19)
*Except for Modified Mini-Mental State Examination results, higher scores indicate worse function.
Table 2: Cox proportional hazard ratios (HR) for time until
death and until the requirement for institutional care
Factor
Death,
HR (95% CI)
Entry into institution,
HR (95% CI)
Age 1.08 (1.07–1.08) 1.15 (1.10–1.13)
Sex 0.83 (0.78–0.89) 1.38 (1.21–1.58)
Education level* 0.98 (0.97–0.99) 0.98 (0.97–0.99)
Modified Mini-Mental
State Examination 0.84 (0.82–0.86) 0.65 (0.60–0.70)
Cumulative Illness
Rating Scale 1.14 (1.11–1.17) 1.22 (1.16–1.27)
CSHA measuring tools
Rules-based definition
of frailty
1.17 (1.13–1.20) 1.27 (1.19–1.35)
Frailty Index 1.26 (1.24–1.29) 1.56 (1.48–1.65)
Function Scale 1.16 (1.13–1.20) 1.29 (1.20–1.39)
Clinical Frailty Scale 1.30 (1.27–1.33) 1.46 (1.39–1.53)
Note: CI = confidence interval, CSHA = Canadian Study of Health and Aging.
All scales were adjusted for age, sex and number of years of education, and recategorized into
7-level scales to compare with the Clinical Frailty Scale.
*Univariate estimate.
Index each correlated to a similar degree with age (0.35 and
0.29, respectively); the 3MS measure of cognition (0.58,
0.59); the Cumulative Illness Rating Scale, which measures
comorbidity (0.43, 0.48); the CSHA Function Score (0.78,
0.74); and the CSHA rules-based frailty definition (0.67
and 0.65, respectively). Reliability between the 2 ratings of
the CSHA Clinical Frailty Scale assessments was very high
(intraclass correlation coefficient 0.97, p < 0.001).
Hazard ratios for death and entry into an institutional
facility (Table 2) in each case showed increasing risk with
increasing frailty (Fig. 1, upper graph). ROC curve analyses
of the CSHA Clinical Frailty Scale and the Frailty Index
revealed similar areas under the curves, a performance bet-
ter than that of the other measures (Table 3). The best
result was achieved for near-term mortality (death within
18 months), with an area under the curve of 0.77.
Similarly, worse frailty was associated with an increased
probability of entering an institutional facility (Fig. 1,
lower graph). The Clinical Frailty Scale and the Frailty In-
dex had comparable performances in ROC analyses, which
again was better than the performance of the 3MS or
Cumulative Illness Rating Scale tools (Table 3). However,
the CSHA Function Scale showed sig-
nificantly better performance than all
other measures in assessing risk for en-
try into an institution.
In multivariable models that adjusted
for age, sex and education (Fig. 1), each
1-category increment of our Clinical
Frailty Scale significantly increased the
medium-term risks (i.e., those within
about 70 months) of death (21.2%,
95% CI 12.5%–30.6%) and entry into
institutional care (23.9%, 95% CI 8.8%–
41.2%).
Interpretation
We have shown that the Clinical
Frailty Scale is an effective measure of
frailty and provides predictive informa-
tion similar to that of other established
tools about death or the need for an
institution. The Clinical Frailty Scale is
easy to use and may readily be adminis-
tered in a clinical setting, an advantage
over the tools previously developed. For
example, counting deficits with the
Frailty Index is easy to understand, and
powerfully correlates the relation be-
tween frailty and death; on the other
hand, it requires the physician to consi-
der a list of no fewer than 70 possible
disorders. The 7-category Clinical Frail-
ty Scale showed good criterion validity,
with a dose–response effect in relation to
5-year prediction of death or entry into
an institutional facility and reasonable
construct validity, with worse health
characteristics associated with increasing
frailty.
The Clinical Frailty Scale mixes
items such as comorbidity, cognitive im-
pairment and disability that some other
groups separate in focusing on physical
frailty.
3
Although support exists for sepa-
rate approaches,
28
consensus does not,
1,2
Rockwood et al
492 JAMC • 30 AOÛT 2005; 173 (5)
6–7
(
691
)
Score
(
n
)
1–3
(
952
)
4
(
349
)
5
(
305
)
Time, mo
0.9
0.3
0.4
0.5
0.6
0.7
0.8
1.0
700102030405060
Probability of survival
0.9
0.3
0.4
0.5
0.6
0.7
0.8
1.0
700102030405060
Time, mo
Probability of avoidance
of institutional care
Score (
n
)
1–3 (
828
)
4 (
256
)
5 (
136
)
6–7 (
66
)
Fig. 1: Kaplan–Meier curves, adjusted for age and sex, for study participants (
n
)
over the medium term (5–6 years), according to their scores on the CSHA Clinical
Frailty Scale. Some scores were grouped. Top: Probability of survival. Bottom:
Probability of avoidance of institutional care.
and there are reasons to be skeptical. The physical frailty
approach rests on unspecified assumptions about an un-
quantitated “physiological reserve”; its predictive validity is
no better than a more comprehensive account. Empirically,
most elderly patients who are physically frail show some
level of disability, although this aspect of the debate de-
pends on the definitions employed
29–32
and in any case
would be captured by our designation of being “apparently
vulnerable.”
Applying the Clinical Frailty Scale to patients requires
judgment. The fabric of individual health has many strands,
and it seems likely that some clinicians sometimes used fac-
tors not precisely specified in our brief set of descriptors.
Some readers might be inclined to view such subjectivity
poorly, but we do not see flexibility as a weakness: Differ-
ent clinicians will emphasize different aspects of illness dif-
ferently — as in, for example, a psychiatrist and a neurol-
ogist each validly concluding, by distinct processes, that a
given patient has frontotemporal dementia. Such flexibility
is widely validated in similar settings.
33–36
It also appears to
us to be analogous to the advanced computing techniques
that we have used in recent inquiries to enhance the per-
formance of the high-dimension Frailty Index.
15,37
For
instance, an artificial neural network can be used to calcu-
late weighted scores, and can significantly improve the
Frailty Index’s predictive performance over an unweighted
version.
15
What an artificial neural network cannot do, however, is
describe which factors most increase risk. This appears to
us to be analogous to clinical judgments about the same
phenomenon. Both clinical judgment and such advanced
computational techniques can be contrasted with a rules-
based frailty approach, which specifies combinations
a priori but at the expense of not including the patients that
most clinicians would recognize as frail.
The present inquiry showed that the predictive validity
of the CSHA’s Frailty Index and Clinical Frailty Scale were
indistinguishable; moreover, both measures performed bet-
ter in this regard than did the rules-based frailty definition.
On these grounds, and given that rules-based combinations
cannot fully embrace the complexity of states in which indi-
vidual people can find themselves, a judgment-based system
seems to be a reasonable way to measure relative fitness and
frailty. For such an instrument to be used routinely, how-
ever, more information is needed about its interrater relia-
bility, which is the subject of additional studies. Until those
study results become available, the Clinical Frailty Scale
can be used to provide broad guidelines for helping to ad-
vise about the best mix of care for elderly patients.
Our data must be interpreted with caution. Although
CSHA was population-based, CSHA-2 clinical examin-
ations overrepresent people with cognitive impairment and
those in institutions. This probably accounts for the Clinical
Frailty Scale’s bimodal distribution, with peaks at 3 (“well,
with treated comorbid disease”) and at 6 (“moderately
frail”). On the other hand, the Clinical Frailty Scale showed
a wider distribution than might be expected with a purely
clinical sample, and our study was large enough to generate
estimates with narrow confidence intervals. The only mea-
sure of test–retest or interrater reliability available to us was
unblinded; that reliability estimate is therefore likely to be
higher than would be the case in usual practice. Category 7
appeared to mix 2 groups that seem distinct: terminally ill
people (who might still be independent) and those who are
totally dependent on others tao carry out their activities of
daily living. Although people in category 7 had a high mor-
tality, these subgroups routinely would be distinguished
clinically; future users of the scale might do well to sub-
divide these groups, especially in acute care settings.
We can envisage future roles for CSHA’s Frailty Index
and Clinical Frailty Scale alike. The judgment-based scale
might be better exploited where clinicians are available who
have experience in the care of elderly people. The index ap-
proach might better serve where such access is unavailable.
The index approach also appears to have some important
mathematical advantages in its scaling that might lead to
novel insights,
2,38,39
especially into matters such as physio-
logic reserve, which is often invoked in relation to frailty
but little measured. Given the increasingly elderly popula-
tion, and the particular challenge posed by elderly people
who are frail, the important questions for researchers now
are how to measure frailty more precisely and how to bet-
ter translate frailty measurement into clinically sensible
tools and practices.
Fitness and frailty in elderly people
CMAJ • AUG. 30, 2005; 173 (5) 493
Table 3: Receiver operating characteristic (ROC) analyses for
adverse outcomes within 70 months
Area under the ROC curve
Assessment tool
Death
Entry into
an institution
Cumulative Illness Rating Scale 0.58 0.62
Modified Mini-Mental State Examination 0.64 0.69
CSHA rules-based definition of frailty 0.66 0.70
CSHA Function Scale 0.68 0.80
CSHA Frailty Index 0.69 0.72
CSHA Clinical Frailty Scale 0.70 0.75
Note: CSHA = Canadian Study of Health and Aging.
This article has been peer reviewed.
From the Division of Geriatric Medicine, Dalhousie University, Halifax, NS
(Rockwood, Song, MacKnight, Mitnitski); the Division of Geriatric Medicine,
McGill University, Montréal, Que. (Bergman); the Division of Geriatric Medicine,
University of Calgary, Calgary, Alta. (Hogan); and the Department of Epidemiol-
ogy and Community Medicine, University of Ottawa, Ottawa, Ont. (McDowell)
Competing interests
: None declared.
Contributors
: Kenneth Rockwood designed the study, wrote the first and final
drafts of the manuscript, and supervised the analyses. Xiaowei Song and Arnold
Mitnitski conducted and verified all the analyses. (Arnold Mitnitski and Kenneth
Rockwood previously devised and tested the Frailty Index.) Kenneth Rockwood,
Chris MacKnight, David Hogan and Howard Bergman examined patients. Ian
McDowell, Chris MacKnight and David Hogan commented on and revised interim
drafts. All authors contributed to and approved the final published version and sup-
port the presented results.
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Rockwood et al
494 JAMC • 30 AOÛT 2005; 173 (5)
Correspondence to: Dr. Kenneth Rockwood, Centre for Health
Care of the Elderly, 1421—5955 Veterans’ Memorial Lane,
Halifax NS B3H 2E1; fax 902 473-1050;
kenneth.rockwood@dal.ca
Acknowledgements
: This analysis was supported by grants from the National
Health Research Development Program of Health Canada (grant no. 6603-1417-55)
and the Queen Elizabeth II Research Foundation. The data reported in this article
were collected as part of the Canadian Study of Health and Aging. The core study
was funded by the Seniors’ Independence Research Program, through the National
Health Research and Development Program, project no. 6606-3954-MC(S). Addi-
tional funding was provided by Pfizer Canada Incorporated through the Medical
Research Council/Pharmaceutical Manufacturers Association of Canada Health
Activity Program, the National Health Research and Development Program, pro-
ject no. 6603-1417-302(R). The study was coordinated through the University of
Ottawa and Health Canada’s Division of Aging and Seniors. Additional funds for
analysis came from the Canadian Institutes for Health Research (CIHR) grant
MOP 62823 and the Dalhousie University Internal Medicine Research Foundation.
Kenneth Rockwood and Chris MacKnight receive CIHR support through Investi-
gator and New Investigator awards, respectively. Kenneth Rockwood is also sup-
ported by the Dalhousie Medical Research Foundation as Kathryn Allen Weldon
Professor of Alzheimer Research. Howard Bergman is Dr. Joseph Kaufman Pro-
fessor of Geriatric Medicine at McGill University, and David Hogan is Brenda
Strafford Foundation Chair in Geriatric Medicine at the University of Calgary.
Fitness and frailty in elderly people
CMAJ • AUG. 30, 2005; 173 (5) 495
Appendix 1: List of variables used by the Canadian Study of Health and Aging to construct the 70-item CSHA Frailty Index
• Changes in everyday activities
• Head and neck problems
• Poor muscle tone in neck
• Bradykinesia, facial
• Problems getting dressed
• Problems with bathing
• Problems carrying out personal grooming
• Urinary incontinence
• Toileting problems
• Bulk difficulties
• Rectal problems
• Gastrointestinal problems
• Problems cooking
• Sucking problems
• Problems going out alone
• Impaired mobility
• Musculoskeletal problems
• Bradykinesia of the limbs
• Poor muscle tone in limbs
• Poor limb coordination
• Poor coordination, trunk
• Poor standing posture
• Irregular gait pattern
• Falls
• Mood problems
• Feeling sad, blue, depressed
• History of depressed mood
• Tiredness all the time
• Depression (clinical impression)
• Sleep changes
• Restlessness
• Memory changes
• Short-term memory impairment
• Long-term memory impairment
• Changes in general mental functioning
• Onset of cognitive symptoms
• Clouding or delirium
• Paranoid features
• History relevant to cognitive impairment
or loss
• Family history relevant to cognitive
impairment or loss
• Impaired vibration
• Tremor at rest
• Postural tremor
• Intention tremor
• History of Parkinson’s disease
• Family history of degenerative disease
• Seizures, partial complex
• Seizures, generalized
• Syncope or blackouts
• Headache
• Cerebrovascular problems
• History of stroke
• History of diabetes mellitus
• Arterial hypertension
• Peripheral pulses
• Cardiac problems
• Myocardial infarction
• Arrhythmia
• Congestive heart failure
• Lung problems
• Respiratory problems
• History of thyroid disease
• Thyroid problems
• Skin problems
• Malignant disease
• Breast problems
• Abdominal problems
• Presence of snout reflex
• Presence of the palmomental reflex
• Other medical history
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