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The AD8
A brief informant interview to detect dementia
J.E. Galvin, MD, MPH; C.M. Roe, PhD; K.K. Powlishta, PhD; M.A. Coats, RN, MSN; S.J. Muich, RN, MSN;
E. Grant, PhD; J.P. Miller; M. Storandt, PhD; and J.C. Morris, MD
Abstract—Background: Brief measures that accurately discriminate normal cognitive aging from very mild dementia are
lacking. Cognitive tests often are insensitive to very mild dementia. Informant-based measures may be more sensitive in
detecting early dementia. Objective: To identify informant-reported clinical variables that differentiate cognitively normal
individuals from those with very mild dementia. Methods: A 55-item battery of informant queries regarding an individu-
al’s cognitive status was derived from a semistructured interview and a consensus panel of dementia experts. The battery
was evaluated with informants for 189 consecutive participants of a longitudinal study of memory and aging and
compared with an independently obtained Clinical Dementia Rating (CDR) score for the participant. Multiple regression
and receiver operator characteristic curves assessed subsets of the items to discriminate between CDR 0 (no dementia)
and CDR 0.5 (very mild dementia). Results: The final version (AD8) querying memory, orientation, judgment, and function
was administered to an additional sample of 112 CDR 0 and 68 CDR 0.5 participants. Using a cut-off of two items
endorsed, the area under the curve was 0.834, suggesting good to excellent discrimination, sensitivity was 74%, and
specificity was 86% (prevalence of 0.38 for very mild dementia). Inclusion of 56 additional individuals with mild to severe
dementia (increasing dementia prevalence to 0.53) increased sensitivity to 85%. Conclusions: The AD8 is a brief, sensitive
measure that reliably differentiates between nondemented and demented individuals. Use of the AD8 in conjunction with
a brief assessment of the participant could improve diagnostic accuracy in general practice.
NEUROLOGY 2005;65:559–564
Alzheimer disease (AD) and other dementias are
both underrecognized and underdiagnosed in the
community.
1-3
This may be due in part to the lack of
brief measures that can discriminate normal aging
from very mild dementia. Tests such as the Mini-
Mental State Examination
4
(MMSE) have a ceiling
effect that makes them insensitive to early signs of
dementia,
5
especially in highly educated individuals,
and they may not be culturally sensitive.
6,7
Other
scales such as the Cognitive Abilities Screening In-
strument
8
and the General Practitioner Assessment
of Cognition
9
have less cultural bias but require ex-
tensive training to administer and generally are too
lengthy for use in general practice. Brief measures
such as the Short Blessed Test
10
(SBT) and the Mem-
ory Impairment Screen
11
are heavily weighted to-
ward memory deficits and may not detect
nonamnestic dementias. The Clock-Drawing Task or
Cube Copying are similarly limited to a single cogni-
tive domain and may not be useful in detecting mild
cases of dementia.
12-14
The Rowland Universal De-
mentia Assessment Scale has been applied in re-
search samples and tests six domains but takes
about 10 minutes to complete.
15
Published criteria for AD diagnosis such as those
developed by the Work Group of the National Insti-
tute of Neurological and Communication Disorders
and Stroke/Alzheimer’s Disease and Related Disor-
ders Association (NINCDS/ADRDA)
16
require stan-
dard assessment of patients. Comparison of
individual performance on cognitive test measures
with normative values, however, may not detect de-
clines that occur in very mild dementia, particularly
in high-functioning individuals.
7,17
Further, brief
objective testing may falsely identify as demented
people with life-long poor cognitive functioning.
Informant-based assessments, on the other hand,
may reveal early cognitive change because of a longi-
tudinal perspective, have face validity, and are es-
tablished in studies characterizing AD and in AD
Additional material related to this article can be found on the Neurology
Web site. Go to www.neurology.org and scroll down the Table of Con-
tents for the August 23 issue to find the title link for this article.
From the Departments of Neurology (Drs. Galvin and Morris, M.A. Coats and S.J. Muich), Anatomy and Neurobiology (Dr. Galvin), Psychology (Drs.
Powlishta and Storandt), and Pathology and Immunology (Dr. Morris) and Division of Biostatistics (Drs. Roe, Grant, and J.P. Miller) and Alzheimer’s Disease
Research Center, Washington University, St. Louis, MO.
Dr. Powlishta’s current address is the Department of Psychology, Saint Louis University, St. Louis, MO.
Supported by grants from the National Institute on Aging (K08 AG20764, P01 AG03991, and P50 AG05681), the Longer Life Foundation, the American
Federation for Aging Research, and the Alan A. and Edith L. Wolff Charitable Trust. Dr. Galvin is a recipient of the Paul Beeson Physician Faculty-Scholar
in Aging Research Award.
Disclosure: The authors report no conflicts of interest.
Received December 13, 2004. Accepted in final form May 4, 2005.
Address correspondence and reprint requests to Dr. J.E. Galvin, Alzheimer Disease Research Center, Washington University School of Medicine, 4488 Forest
Park, Suite 130, St. Louis, MO 63108; e-mail: galvinj@neuro.wustl.edu
Copyright © 2005 by AAN Enterprises, Inc. 559
clinical trials.
18-21
Global rating systems such as the
Clinical Dementia Rating
18
(CDR) and the Informant
Questionnaire on Cognitive Decline in the Elderly
19
(IQCODE) incorporate information from a collateral
source to assess change in the patient’s cognitive
ability to conduct their accustomed activities. These
systems do not require a baseline assessment for
comparison and minimize issues such as practice ef-
fects and educational and sociocultural influences
that confound interpretation of performance-based
assessments.
20,21
Current informant-based assess-
ments, however, are lengthy and require interpreta-
tion by an experienced clinician; therefore, they are
difficult to use in community practice. Given the
brief period available to primary care physicians in a
standard office visit, there will likely be some accept-
able trade-off to the clinician, sacrificing specificity
and sensitivity to detect dementia to keep the clini-
cal tool brief. Given that requirement, our goal was
to develop a dementia screening instrument that
could be completed in a just in a few minutes with
maximally balanced sensitivity and specificity.
We developed a brief dementia assessment that
includes both performance-based assessment of the
patient and a brief informant interview. We identi-
fied clinical variables that we believed would distin-
guish individuals with very mild dementia from
those without dementia based on a review of the
literature and our experience with the semistruc-
tured interview of the informant in the research pro-
tocol used to derive the CDR
18
(we also use
information from the participant to derive the CDR).
We identified 55 questions asked of the informant
about the cognitive function of the participant that
were thought to assist in dementia detection and
when combined with a brief objective assessment of
the participant might serve as a diagnostic screening
tool. The results were compared with an indepen-
dently derived CDR rating of the participant. Data
from these participants were then used to develop an
eight-item informant interview (the AD8) to discrim-
inate between CDR 0 (nondemented) and CDR 0.5
(very mildly impaired conditions). The psychometric
and discriminative properties of the AD8 were then
tested prospectively in a second sample. Evaluation
of the AD8 in combination with the brief participant
assessment is ongoing; here we describe the develop-
ment and validation of the AD8 and its correlation
with other dementia screening measures.
Methods. Clinical data. All participants were volunteers who
enrolled in a longitudinal study (initiated in 1979 and studying to
date 2,049 individuals) of healthy aging and dementia. Partici-
pants are recruited via word of mouth, public service announce-
ments, and referrals from physicians in the St. Louis area. Both
nondemented and demented participants underwent identical an-
nual assessments. There are currently 549 active participants.
The Washington University Human Studies Committee approved
all procedures.
Experienced clinicians (neurologists, psychiatrists, geriatri-
cians, and masters-prepared geriatric nurse specialists) conducted
independent semistructured interviews with the participant and a
knowledgeable collateral source (usually the spouse or close fam-
ily member)22 to capture features suggestive of a dementing disor-
der. The diagnostic criteria for dementia of the Alzheimer type
used in this study (impairment in memory and at least one other
cognitive domain and interference with daily activities) are com-
parable with the Diagnostic and Statistical Manual of Mental
Disorders IV definition23 and of the “probable AD” category in the
NINCDS/ADRDA criteria.16 Wherever possible, published criteria
were used for other dementing disorders, including dementia with
Lewy bodies (DLB)24 and vascular dementia (VaD).25
The CDR was used to determine the presence or absence of
dementia and to stage its severity.18 Using all information from
the clinical assessment protocol but without reference to the indi-
vidual’s psychometric performance, the CDR rates cognitive func-
tion in each of six categories (memory, orientation, judgment and
problem solving, and performance in community affairs, home and
hobbies, and personal care). The global CDR is derived from the
individual ratings in each of the six categories, where CDR 0
indicates no dementia. CDR 0.5 may represent very mild demen-
tia or in some cases with minimal impairment or uncertain or
questionable dementia. CDR 1 corresponds to mild, CDR 2 to
moderate, and CDR 3 to severe dementia.18 The sum of the indi-
vidual category ratings (sum of boxes [SB]) provides a quantita-
tive expansion of the CDR and ranges from 0 (no impairment) to
18 (maximum impairment).26 In our sample, the CDR 0.5 rating
equates with very mild dementia27 and is the threshold to distin-
guish nondemented (CDR 0) from demented (CDR ⱖ0.5) status. In
other samples CDR 0.5 has been used as the threshold for the
diagnosis of mild cognitive impairment.28 In both cases, the CDR
is useful to detect the change in cognitive abilities from a prior
level of function and also to assess interference with accustomed
activities. The interrater reliability of the CDR has been estab-
lished,29 and its validity has been established by correlation with
neuropathologic features observed at autopsy.26 Therefore, the
CDR was used as the gold standard for recognition of cognitive
impairment in this study.
Instrument development. The AD8 was developed using a
combination of expert clinical judgment and statistical modeling.
A list of 55 questionnaire items was developed based on an exten-
sive review of the literature, our experience with semistructured
informant interviews, the consensus opinion of four dementia ex-
perts (a neurologist, a psychologist, and two advanced practice
nurses), and the results of a previously collected telephone survey
of community-dwelling older adults (unpublished data). Three re-
sponse options were offered with instructions: 1) yes, a change; 2,
no, no change; or 3), N/A, don’t know. Between June 3, 2002, and
February 21, 2003, the 55-item questionnaire was administered to
290 consecutive collateral sources (CSs) of study participants at
their annual assessment. None of the 55 items was contained
within the structured part of the interview. An open-ended part of
the interview allows clinicians to ask nonstandard questions that
probe changes in memory, orientation, and other cognitive do-
mains specific to that participant. To maximize its ability to dis-
criminate between normal cognitive aging and very mild
dementia, the AD8 was developed using data from the CS re-
sponses of participants who were age 55 or older and who received
a CDR score of 0 (n ⫽86) or 0.5 (n ⫽103) at their assessment.
There were no significant differences between the CDR groups
with regard to age, gender, race, education, or the relationship
between the CS and the participant.
Because the AD8 was conceptualized as a brief instrument, the
RSQUARE selection method (SAS version 8 for Sun OS, Cary,
NC) was used to reduce the number of items. This method finds
subsets of independent variables that best predict a dependent
variable using multiple linear regression. After specifying the sub-
set size, the procedure computes all possible regressions and their
R
2
value so the models’ predictive ability can be compared. The
procedure was carried out within the CDR 0.5 sample (n ⫽103)
using the CDR SB as the dependent variable. All 55 items were
used as predictor variables, and subset size was set to 10. Thus,
regressions were calculated for all possible 10-item combinations
of the 55 predictor variables.
Ten models with the largest R
2
values were examined. Nine
models contained negative regression coefficients indicating the
statistical phenomenon of suppression. On a practical level, a
negative coefficient means that the variable would have to be
subtracted from the total, whereas the other variables would be
added together. Because the R
2
values of the 10 models were
560 NEUROLOGY 65 August (2 of 2) 2005
almost identical (range ⫽0.7407 to 0.7458), the model without
negative coefficients was chosen (R
2
⫽0.744).
Further analysis of this 10-item model led to several revisions.
Two items from this model were rarely endorsed: wears seasonally
inappropriate clothing (3.9%) and trouble dressing (1.9%); there-
fore, an index score was also computed using only eight items.
Data from the CDR 0 and CDR 0.5 groups were used to generate
receiver operator characteristic (ROC) curves to compare the 8-
and 10-item indexes. These analyses demonstrated that the pre-
dictive ability of the 8-item scale (area under the curve [AUC] ⫽
0.852) was equal to that of the 10-item scale (AUC ⫽0.853).
The eight-item scale was then distributed to each member of
the research team for review. Based on comments from the re-
search team, two other items (difficulty voting and confuses family
relationships) that were endorsed by ⬍10% of the sample were
deleted; these are behaviors that are more common in later stages
of dementia. Based on a clinical rather than statistical perspec-
tive, two additional items (consistent problems with memory or
thinking and reduced interest in hobbies and activities) were
added to enhance the face validity of the scale to ensure that the
tool included questions pertaining to memory and activities of
daily living. The ability of the new eight-item scale to predict
membership in the CDR 0.5 group vs the CDR 0 group was com-
pared with that of the original eight-item index. Inspection of the
ROC curves and the area under those curves indicated that the
revised eight-item scale (the AD8) yielded the best predictive abil-
ity (AUC for final AD8 ⫽0.870).
The final eight-item version of the AD8 (see figure E-1 on the
Neurology Web site at www.neurology.org) queries the CS about
the participant’s cognitive abilities in the areas of memory (consis-
tent problems with memory, repetition, remembering appoint-
ments), temporal orientation, judgment (making decisions,
handling finances), and function (reduced interest in activities,
use of appliances). The total AD8 score is generated by summing
the number of items responded to with “yes, a change”; thus,
possible AD8 scores range from 0 to 8. As described earlier, the
AUC was 0.870 in the developmental sample, suggesting good to
excellent discrimination between CDR 0 and CDR 0.5 groups, and
was comparable to the full 55-item instrument (AUC ⫽0.895).
The AD8 was then administered for a 6-month period to a new
sample from our longitudinal study at their annual assessment.
The AD8 was administered to the CS prior to the clinician’s inter-
view with the CS and assessment of the participant. The clinician
was not told the answers given by the CS. At the end of the
assessment, the clinician generated an independent CDR rating
for the participant according to our standard procedures.
Statistical analysis. Descriptive statistics were used to sum-
marize sample characteristics as well as AD8 scores at each CDR
level. To demonstrate how the AD8 scores compare with the inde-
pendently generated CDR rating and brief office-based objective
measures, correlations between AD8, CDR, MMSE, and SBT
scores were determined using Pearson product–moment correla-
tion coefficients. We hypothesized that higher AD8 scores would
represent more severe stages of dementia and correlate with
higher CDR stages and worsening performance on the MMSE and
SBT. ROC curves and AUC were generated to reflect graphically
and quantitatively the ability of the AD8 to discriminate between
participants with CDR 0 and CDR 0.5 and between those with
CDR 0 and CDR ⱖ0.5. Classification tables were constructed, and
the sensitivity, specificity, and positive and negative predictive
values of the AD8 were calculated. All statistical analyses were
conducted using SAS.
Results. Sample characteristics. The AD8 was admin-
istered to 236 participants between October 6, 2003, and
April 2, 2004. Characterization of CDR stages and diag-
noses of the sample are shown in table 1. The participant’s
mean age at time of assessment was 78.1 ⫾9.2 years
(range 55 to 102 years), and 53% were women. The collat-
eral sources were spouses (52%), children (29%), friends
(10%), and other sources such as social workers, case man-
agers, and health aides (9%). The participant’s cognitive
status ranged from nondemented (47% CDR 0) through all
stages of dementia (very mild, CDR 0.5 ⫽29%; mild, CDR
1⫽18%; moderate, CDR 2 ⫽5%; and severe, CDR 3 ⫽
1%). Clinical diagnoses from the standard assessment in-
cluded nondemented elders (47% of sample), uncertain or
questionable dementia (12%), and demented individuals
(41%). Dementia diagnoses were largely made up of de-
mentia of the Alzheimer type; however, other dementia
diagnoses included mixed dementia, VaD, and DLB. The
AD8 was administered to the CS by the center’s secretarial
staff, taking on average under 3 minutes to complete.
AD8 scores compared with CDR stages. Total AD8
scores were compared by CDR stages determined indepen-
dently by experienced clinicians (table 2). Those individu-
als who were rated as CDR 0 had a mean AD8 score of 0.6
(range 0 to 5) compared with individuals who were rated
as having at least very mild dementia (CDR ⱖ0.5) who had
a mean score of ⱖ2.91 (range 0 to 8).
Within the CDR 0 group, six individuals had AD8
scores of ⬎4. There was no difference between diagnoses or
the type of CS to distinguish these CDR 0 individuals from
those with AD8 scores of ⬍4. Several characteristics, how-
ever, did distinguish the two groups. First, the CSs of CDR
0 individuals with high AD8 scores were more likely (5/6 or
83%) to endorse the AD8 question dealing with “consistent
problems with thinking and memory” than the CSs of CDR
0 individuals with low AD 8 scores (5/101 or 5%). Second,
the six CDR 0 individuals with AD8 score of ⬎4 had a
lower mean MMSE score than CDR 0 individuals with
AD8 scores of ⬍4 (26.3 vs 28.8; p⫽0.0005). It is possible
Table 1 Diagnosis and dementia severity of sample (n ⫽236)
Diagnoses CDR 0 CDR 0.5 CDR 1 CDR 2 CDR 3
No dementia 111 0 0 0 0
Uncertain/questionable 0 28 0 0 0
DAT 0 27 23 5 0
DAT with atypical
features
010 16 5 1
Mixed DAT/VaD 0 1 1 1 0
VaD 0 1 1 0 0
DLB 0 0 1 0 1
Incipient dementia
(non-DAT)
12 000
CDR ⫽Clinical Dementia Rating; DAT ⫽dementia of the Alz-
heimer type; VaD ⫽vascular dementia; DLB ⫽dementia with
Lewy bodies.
Table 2 Total AD8 score by Clinical Dementia Rating (CDR)
stage
CDR n Mean SD Min Max
0 112 0.60 1.12 0 5
0.5 68 2.91 2.05 0 8
1 43 6.00 1.51 1 8
2 11 6.45 1.37 5 8
3 2 5.50 3.54 3 8
CDR 0 ⫽nondemented; CDR 0.5 ⫽very mildly demented; CDR
1⫽mild dementia; CDR 2 ⫽moderate dementia; CDR 3 ⫽se-
vere dementia.
August (2 of 2) 2005 NEUROLOGY 65 561
that these individuals had early cognitive change although
insufficient to warrant a dementia diagnosis.
Within the CDR 0.5 group, there were six individuals
with total AD8 scores of ⬎6. There was no differences in
caregiver type or questions endorsed, but several features
distinguished these individuals from the rest of the CDR
0.5 group. Those participants with AD8 scores of ⬎6 had
lower MMSE scores (24.5 vs 26.8; p⫽0.048), higher SBT
scores (19.3 vs 10.8; p⬍0.0001), and higher CDR SB
scores (2.9 vs 1.5; p⫽0.004). These individuals might be
further along in the course of disease. There is the possibil-
ity that mood disorders might play a role.
The CDR 0.5 group with AD8 scores of ⬎6 also were
more likely to have a history of a mood disorder (4/6, 67%)
compared with the rest of the CDR 0.5 group (17/62, 27%).
Longitudinal follow-up of these individuals will be helpful
to answer these questions.
Discriminative ability of the AD8. ROC curves were
generated to measure the effectiveness of the AD8 in clas-
sifying CDR 0 (nondemented) vs CDR 0.5 (very mild de-
mentia) participants. The AUC (figure 1) is 83%,
suggesting good to excellent ability to discriminate be-
tween CDR 0 and CDR 0.5 groups. Using a cut-off score of
ⱖ2 on the AD8 to predict dementia yielded the most desir-
able combination of sensitivity (74%) and specificity (86%)
(table 3). With a prevalence of 38%, the positive predictive
value (the probability that someone with an AD8 score of
ⱖ2 has dementia) was 76%, whereas the negative predic-
tive value (the probability that someone with an AD8 score
of ⬍2 is nondemented) was 84%.
When predicting membership in the demented group
(CDR ⱖ0.5) vs status as a nondemented participant (CDR
0), the ROC area under the curve (figure 2) was 90%,
suggesting excellent discriminative ability. Sensitivity in-
creased to 85%, with specificity remaining at 86% (see
table 3). The positive predictive value increased (87%) and
negative predictive value (84%) remained essentially the
same with the increased prevalence rate (53%) and inclu-
sion of more severely demented individuals.
Correlation of AD8 with other measures of cognitive sta-
tus. Strong correlations were demonstrated between the
AD8 and the CDR staging (r⫽0.74, p⬍0.0001) and
between AD8 and SBT scores (r⫽0.58, p⬍0.0001). An
inverse correlation was found between the AD8 and
MMSE scores (r⫽⫺0.64, p⬍0.0001).
Discussion. The AD8 is a brief informant-based
measure that reliably differentiates nondemented
from demented individuals and is sensitive to the
earliest signs of cognitive change as reported by an
informant. The AD8 is highly correlated with our
gold standard, the CDR, as well as performance on
brief objective measures such as the MMSE and
SBT. The AD8 took the CS ⬍3 minutes to complete
and was administered by clerical staff.
The goals of any screening test are to separate
people with a high probability of having the disease
from those with a low probability and to presump-
tively identify unrecognized disease.
30
Diagnostic
confirmation is generally required. An effective
screening test should be inexpensive, and its charac-
teristics should include reliability, sensitivity, speci-
ficity, social acceptability, safety, and brevity.
26
We
have presented data indicating that the AD8 meets
all of these requirements and discriminates cogni-
tively healthy older adults from individuals at the
very earliest symptomatic stage of dementing ill-
nesses. The AD8 is currently being used as part of a
brief dementia detection instrument (in conjunction
with a patient assessment) to evaluate patients in
community settings. If the instrument were used to
select research participants, a different cut-off score
might be chosen depending on the costs of identify-
ing individuals (sensitivity) vs the costs of screening
and excluding them (specificity).
Figure 1. Receiver operator characteristic (ROC) curve for
CDR 0 vs CDR 0.5: ROC curve comparing the AD8 scores
of nondemented (CDR 0) participants with the AD8 scores
of participants with very mild dementia (CDR 0.5). The
area under the ROC curve is 0.834, suggesting good to ex-
cellent ability of the AD8 to discriminate between groups.
Table 3 Classification using AD8 score of ⬎2 for CDR 0 and 0.5
groups and for all participants with CDR of ⬎0.5
AD8 score
CDR 0,
n⫽112
CDR 0.5,
n⫽68
CDR ⱖ0.5,
n⫽124
0 or 1 (not demented) 96 18 19
⬎2 (demented) 16 50 105
CDR ⫽Clinical Dementia Rating.
Figure 2. Receiver operator characteristic (ROC) curve for
CDR 0 vs CDR ⱖ0.5: ROC curve comparing the AD8
scores of nondemented (CDR 0) participants with the AD8
scores of participants with at least very mild dementia
(CDR ⱖ0.5). The area under the ROC curve is 0.904, sug-
gesting excellent ability of the AD8 to discriminate be-
tween groups.
562 NEUROLOGY 65 August (2 of 2) 2005
A number of brief screening measures are already
in use, but most are based on patient performance
and are therefore unable to detect or quantify change
from previous levels of function. Some performance-
based measures are also insensitive to subtle
changes in high-functioning individuals who may
score well within the normal range through the early
stages of dementia. These same measures also may
prevent detection of dementia in individuals with
poorer lifelong abilities. Further, many cognitive
tests are culturally insensitive and may underesti-
mate the abilities of African American and other mi-
nority groups.
31
Informant-based assessments provide an opportu-
nity for the clinician to assess change from the pa-
tient’s prior level of function and determine
interference with the patient’s accustomed function-
ing in daily tasks. The use of an informant permits
the use of patients as their own control while elimi-
nating the need for baseline assessments. The time
required to complete the informant interview to de-
rive the CDR, however, is greater than an average
office visit permits. Other informant-based inter-
views such as the IQCODE
32,33
are also too lengthy
for general use. The Observation List for Early Signs
of Dementia
34
is a brief 12-item measure; however, it
is performed by the physician rather than caregivers
or family members. The physician does not have as
much opportunity to observe the patient as does a
family member.
A potential drawback of the AD8 is that knowl-
edgeable informants may not be readily available.
The validity of using informant-based assessments
has been addressed by several authors.
35-37
In gen-
eral, informants who live with the patient are able to
give more accurate reports than informants who do
not. Spouses are generally more accurate than other
informant relationship types. The patient’s educa-
tional level, social status, or neuropsychiatric symp-
toms do not appear to affect informant accuracy.
34
In
the study, we report data from several different in-
formant relationships, ranging from spouse to close
friends, social workers, or paid caregivers.
The sample for our study was not population
based; as with any volunteer sample, selection biases
limit generalization of the results. Our sample was
largely Caucasian, so it is unknown if these results
generalize to other ethnicities. Because the AD8 re-
quires only comment on observable change in the
patient’s cognitive abilities, however, it is less apt to
be biased by gender, education, or ethnicity. Our con-
venience sample includes community volunteers
rather than referrals from memory disorder clinics,
and the participants’ gender and education at-
tributes reflect those of the similarly aged population
in the St. Louis metropolitan area. The sample is
well characterized, enabling comparison of the AD8
with the longer semistructured interview used to de-
rive the CDR as a gold standard.
We are now testing the psychometric properties of
the AD8 in a clinic population alone and in combina-
tion with brief objective measures of the participant’s
cognitive function. The use of the AD8 in conjunction
with a brief cognitive assessment could improve di-
agnostic accuracy in general practice and may be
applicable for dementia screening in clinical trials,
community surveys, and epidemiologic studies.
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RESIDENT AND FELLOW PAGE
Call for teaching videos
The Neurology Resident page is featured online at www.neurology.org. The Editorial Team of this section is seeking
teaching videos that will illustrate classic or uncommon findings on movement disorders. Such videos will aid in the
recognition of such disorders. Instructions for formatting videos can be found in the Information for Authors at
www.neurology.org. Please contact the Editor, Karen Johnston (kj4v@virginia.edu), for more information or submit
teaching videos online at http://submit.neurology.org.
564 NEUROLOGY 65 August (2 of 2) 2005