RESEARCH ARTICLE Open Access
Prevalence and features of ICF-disability in Spain
as captured by the 2008 National Disability
Survey
Sarah Maierhofer*, Javier Almazán-Isla, Enrique Alcalde-Cabero and Jesús de Pedro-Cuesta
Abstract
Background: Since 1986, the study of disability in Spain has been mainly addressed by National Disability Surveys
(NDSs). While international attempts to frame NDS designs within the International Classification of Functioning,
Disability and Health (ICF) have progressed, in general, the ICF has hardly been used in either the NDS or
epidemiological studies. This study sought to identify ICF Activity- and Participation-related content in the most
recent Spanish NDS, the 2008 Survey on Disabilities, Independence and Dependency Situations (Encuesta sobre
discapacidades, autonomía personal y situaciones de Dependencia - EDAD 2008), and estimate the prevalence of such
ICF-framed disability.
Methods: EDAD 2008 methods and questions were perused. Of the 51 EDAD items analysed, 29 were backcoded
to specific d2-d7 domains of the ICF Checklist and, by rating the recorded difficulty to perform specific tasks with
or without help, these were then taken as performance and capacity respectively. A global ICF score was also
derived, albeit lacking data for d1, “Learning and applying knowledge”, d8, “Major Life Areas” and d9, “Community,
Social and Civic Life”. Data were grouped by sex, age, residence and initial positive screening, and prevalence
figures were calculated by disability level both for the general population, using the originally designed weights,
and for the population that had screened positive to disability. Data for institutionalised persons were processed
separately.
Results: Crude prevalence of ICF severe/complete and moderate disability among the community-dwelling
population aged ≥6 years was 0.9%-2.2% respectively, and that of severe/complete disability among persons living
in sheltered accommodation was 0.3%.
Prevalence of severe/complete disability was: higher in women than in men, 0.8% vs. 0.4%; increased with age; and
was particularly high in domains such as “Domestic Life”, 3.4%, “Mobility”, 1.8%, and “Self-care”, 1.9%, in which
prevalence decreased when measured by reference to performance. Moreover, global scores indicated that severe/
complete disability in these same domains was frequent among the moderately disabled group.
Conclusions: The EDAD 2008 affords an insufficient data set to be ICF-framed when it comes to the Activity and
Participation domains. Notwithstanding their unknown validity, ratings for available ICF domains may, however, be
suitable for consideration under the ADL model of functional dependency, suggesting that there are approximately
500,000 persons suffering from severe/complete disability and 1,000,000 suffering from moderate disability, with
half the latter being severely disabled in domains capable of benefiting from technical or personal aid. Application
of EDAD data to the planning of services for regions and other subpopulations means that need for personal help
must be assessed, unmet needs ascertained, and knowledge of social participation and support, particularly for the
* Correspondence: sarah.maierhofer@gmx.net
Department of Applied Epidemiology, National Centre of Epidemiology-
Consortium for Biomedical Research in Neurodegenerative Diseases (Centro
de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas
- CIBERNED), Carlos III Institute of Health, Av. Monforte de Lemos 5, 28029
Madrid, Spain
Maierhofer et al. BMC Public Health 2011, 11:897
http://www.biomedcentral.com/1471-2458/11/897
© 2011 Maierhofer et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative
Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and
reproduction in any medium, provided the original work is properly cited.
mentally ill, improved. International, WHO-supported co-operation in ICF planning and use of NDSs in Spain and
other countries is needed.
Keywords: ADL, Disability, Epidemiology, ICF, Prevalence, Survey, WHO
Introduction
The World Health Organization (WHO) approved the
International Classification of Functioning, Disability
and Health (ICF) in 2001 as a framework and classifica-
tion for understanding the impact of health conditions
on functioning and disability [1]. The ICF conceptual
framework encompasses different components, such as
body functions, body structures, activities and participa-
tion, with some personal and environmental factors
being included among the causes of disability [2]. The
ICF enables individuals’ functioning and disability to be
comprehensively described and categorised in a way that
is systematic, standardised and readily understandable
by all health professionals and social workers involved
in the care and support of patients [2]. The ICF is
increasingly used in different sectors, including health,
social affairs, labour and education [3,4].
Conceivably, the most powerful and regularly used
tools for describing how disability affects citizens and
supporting social policies are National Disability Surveys
(NDSs). Early efforts by the Disability Tabulations (DIS-
TAB) group, including rigorous selection of questions
from five NDSs and backcoding these to the ICF, sug-
gested that cross-country comparisons would be
restricted to comparable backcoded questions, and that
the best basis for international comparability would thus
be for questions’ focus and format to be structured to
the ICF during the surveys’ development phase [5]. Mul-
horn and Threats, using the ICF, described several-fold
variations in age- and sex-specific prevalence of speech
and hearing limitations across five countries included in
the DISTAB study, and revealed difficulties in compar-
ing figures based on measures of differing sensitivity [6].
Recently, international action to understand disability in
populations was led by the Washington City Group (a
working group of the United Nations) [7]. Using the
ICF to develop the Irish National Disability Survey
resulted in a broader range of disabilities encompassed
and the incorporation of policy-relevant environmental
factors, and prompted a discussion on ethics [8].
While it would seem that the ICF capacity and perfor-
mance qualifiers are considered useful by rehabilitation
and social workers [9], the use of capacity and perfor-
mance prevalence data for assessing or developing social
services and policies appears to have been less explored.
Stineman et al, after confirmatory factor analysis of a
large US population, proposed that a standard set of
ICF core chapters -mobility, self-care and domestic life-
could help link and co-ordinate care across general
practitioners, rehabilitation professionals and social ser-
vices, as well as the acute and long-term care sectors
[10]. In Spain, a personal disability index has been pro-
posed, based on unselected disabilities registered in the
1999 NDS and taking into account the severity and
number of hours of personal help received per week
[11].
The type of disability data collected among the Span-
ish population has changed over the years. National and
certain regional health surveys contain specific informa-
tion on impairments, limitations and restrictions
assessed using patient-reported outcomes, such as the
EQ-5, as well as time received from caregivers [12]. The
large-scale, nation-wide household surveys conducted by
trained interviewers in 1986 and 1999 (http:// http://
www.ine.es/) were developed using the framework of the
International Classification of Impairments, Disabilities
and Handicaps (ICIDH). The most recent of these was
the 2008 Survey on Disabilities, Independence and
Dependency Situations (Encuesta sobre discapacidades,
autonomía personal y situaciones de Dependencia -
EDAD 2008) [13-15], which partly incorporated the
ICF’s understanding of disability and some of its
concepts.
Accordingly, this study sought: (a) to explore the
potential of EDAD 2008 data for an ICF-based interpre-
tation, detect any ICF-biased aspects and implement a
specific application of the EDAD 2008 after ICF re-
structuring; (b) to quantify prevalence of disability for
selected ICF domains and for an individual ICF global
score; and, (c) to describe severity patterns among the
disabled population.
Methods
The EDAD 2008
Study population and sampling methodology
The study population covered by the EDAD 2008
[16,17] consisted of two residence-based population
samples, one community-dwelling and the other institu-
tionalised. For the community-dwelling sample, a two-
step, stratified, random sample was used to provide a
representative sample for each province: firstly, a sample
of census sections was drawn, and a sample of family
dwellings was then randomly drawn within each section.
Thereafter, all households within the dwelling were
group screened, with one member of each household
being interviewed as the main informant [16,17]. A total
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of 258,187 persons living in 91,290 households were
thus screened for disability.
In the case of institutions, a sample of Spanish resi-
dential centres and hospitals, representative of the coun-
try’s Autonomous Regions, was drawn [16,17]. The
centres had been classified into two different types,
namely: (a) home or residential centres; and (b) psychia-
tric or geriatric hospitals or centres for disabled persons.
At each centre, a random sample of inhabitants was
drawn, yielding a sample of 10,567 institutionalised
persons.
Individually tailored data-collection
For screening purposes, a catalogue of 44 questions
about possible “disabilities” read verbatim, was pre-
sented to the main informant of each household. It
addressed the following eight domains: vision; audition;
communication; learning and application of knowledge
and performance of tasks; mobility; self-care; domestic
life; interaction and interpersonal relationships [16-19].
Persons for whom at least one of these questions was
answered in the positive were then examined in depth,
using a detailed disability questionnaire, covering the
above-mentioned eight domains, medical conditions,
diagnoses, professional life, education, discrimination,
social contacts, accessibility and main caregivers. For
some items, the level of difficulty experienced in a
given item was measured against two different back-
grounds, namely, the difficulty encountered when per-
forming without aid and that encountered when
performing with technical or personal aid [18,19]. In
addition, the technical or “de facto“ personal help
received was recorded. For subjects aged under 6
years, an adapted version of the questionnaire was
used [18,19]. To evaluate the disabilities of children
aged < 6 years, an informant was given a list of possi-
ble limitations and asked to select those that were pre-
sent. All institutionalised persons allocated to the
sample were interviewed with an adapted version of
the detailed questionnaire used for the household-
based disability study.
Database structure and records on study
The National Institute of Statistics (Instituto Nacional
de Estadística - INE) provided us with individual EDAD
2008 records. Following the survey format, the data
were organised into four data sets, i.e., one covering all
persons screened in households (denoted as household
data set), one covering persons who screened positive
and answered the detailed questionnaire about their dis-
abilities (disability data set), one covering positively
screened children (data limitations), and lastly, one cov-
ering all institutionalised persons (data centres). To
cover specific issues of relevance, we used data from the
above-mentioned four data sets, selecting the most
appropriate for any given purpose.
ICF framing of EDAD 2008 data
ICF-EDAD 2008 cross-walking; ICF backcoding of selected
EDAD 2008 variables
This study disregarded ICF components featured under
“Body Structures” or “Body Functions” and the so-called
“Contextual Factors”, focused on ICF categories shown
under the “Activity and Participation” section (corre-
sponding to ICF codes beginning with the letter d) and,
for cross-comparison purposes, selected those included
in the ICF Checklist (http://www.who.int/classifications/
icf/training/icfchecklist.pdf) [20]. An important reason
for using the frame of the ICF Checklist rather than
that of another instrument, such as the WHODAS-2, is
that the former incorporates capacity and performance
qualifiers. After examining ICF Checklist items one-by-
one and initially selecting the most likely corresponding
variables from the EDAD 2008 disability questionnaire,
data collected by the EDAD 2008 were then imported to
individual ICF Checklist records, as indicated in Table
1. As will be seen from this table, almost all domain-d2
to -d7 items included in the ICF checklist are repre-
sented in the EDAD 2008. However, appropriate infor-
mation for domains d1, “Learning and applying
knowledge”, d8, “Major life areas”, and d9, “Community,
social and civic life”, was not found, despite the fact that
data on educational level, occupational status, monthly
income, feeling of discrimination and spare-time activ-
ities were available in the EDAD 2008. Although the
EDAD 2008 sometimes contains limited information on
a subject’s social activities, e.g., leisure-time reading, or
job status, it does not indicate whether the person in
question experiences any problems, i.e. restrictions, in
performing such activities. In a second step, following
review and reviewer-recommended external expert con-
sultation, a number of variables were additionally
dropped from those that had been initially selected.
Consequently, the ICF Checklist frame resulting from
the EDAD 2008 questionnaire was an incomplete ver-
sion, since a considerably high number of codes were
rejected for data import and left as empty codes after
these two steps (see Table 1).
In accordance with a recognised, optional interpreta-
tion of capacity and performance as relating to difficul-
ties in the absence or presence of technical and personal
help, we took advantage of the above information on
difficulty encountered with and without technical or
personal aid to derive firstly a measure of capacity and
thence a measure of performance from the EDAD 2008,
both recorded in each individual ICF-framed incomplete
Checklist record. In practice, measurements were taken
in such a way that, if the answer about receiving any
type of aid (technical, personal or both) was positive,
the level of performance was assessed. To sum up, in
the case of selected variables (see Table 1), two ICF
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Table 1 EDAD 2008 items of potential interest and those finally selected for ICF backcoding*.
ICF Checklist variables EDAD 2008 variables considered (regardless of selection) EDAD 2008 item used
Short list of activity and
participation domains
Variable Content of EDAD 2008 variables Capacity Performance
d1. Learning and applying knowledge
d110 Watching APR_14 to hold a gaze or pay attention when listening 14.2 14.2
d115 Listening APR_14 to hold a gaze or pay attention when listening 14.2 14.2
d140 Learning to read APR_15 to learn to perform simple tasks 15.2 15.2
d145 Learning to write APR_15 to learn to perform simple tasks 15.2 15.2
d150 Learning to calculate APR_15 to learn to perform simple tasks 15.2 15.2
d175 Solving problems
d2. General tasks and demands
d210 Undertaking a single task APR_16* to perform simple tasks 16.2 16.3.bpt
d220 Undertaking multiple
tasks
APR_17* to perform complex tasks 17.2 17.3.bpt
d3. Communication
d310 Communicating with –
receiving – spoken messages
COM_9* to understand the meaning of what other persons say 9.2 9.3.bp
d315 Communicating with –
receiving – non-verbal
messages
COM_11* to understand and express yourself via gestures, symbols, illustrations or
sounds
11.2 11.2
d330 Speaking COM_8* to speak intelligibly or utter coherent phrases 8.2 8.3.bt
d335 Producing non-verbal
messages
d350 Conversation COM_12* to hold a dialogue and exchange ideas with one or more persons 12.2 12.2
d4. Mobility
d430 Lifting and carrying
objects
MOV_24* to lift or carry objects 24.2 24.3.bpt
d440 Fine hand use MOV_26* to lift or carry small objects 26.2 26.3.bpt
d450 Walking MOV_20*m to walk and move inside the home 20.2 20.3.bpt
MOV_21*m to walk and move around the home 21.2 21.3.bpt
d465 Moving around using
equipment
d470 Using transportation MOV_22* to get around via passenger transport 22.2 22.3.bpt
d475 Driving MOV_23* to drive vehicles 23.2 23.3.bt
d5. Self-Care
d510 Washing oneself AUT_27* to wash or dry different body parts 27.2 27.3.bpt
d520 Caring for body parts AUT_28* to perform basic grooming 28.2 28.3.bpt
d530 Toileting AUT_29max to carry out activities related to urination 29.2 29.3.bpt
AUT_30*max to carry out activities related to defecation 30.2 30.3.bpt
AUT_31*max to carry out activities related to menstrual care (only for women) 31.2 31.3.bpt
d540 Dressing AUT_32* to dress or undress 32.2 32.3.bpt
d550 Eating AUT_33 to eat and drink 33.2 33.3.bpt
d560 Drinking AUT_33 to eat and drink 33.2 33.3.bpt
d570 Looking after one’s
health
AUT_34*max to follow medical prescriptions 34.2 34.3.bpt
AUT_35*max to avoid dangerous situations 35.2 35.3.bpt
d6. Domestic life
d620 Acquisition of goods and
services
VDOM_36* to do shopping 36.2 36.3.bpt
d630 Preparation of meals VDOM_37* to prepare meals 37.2 37.3.bpt
d640 Doing housework VDOM_38* to carry out housework 38.2 38.3.bpt
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Table 1 EDAD 2008 items of potential interest and those finally selected for ICF backcoding*. (Continued)
d660 Assisting others
d7. Interpersonal interactions and relationships
d710 Basic interpersonal
interactions
INTER_39* to show other persons affection, respect or transmit feelings 39.2 39.2
d720 Complex interpersonal
interactions
d730 Relating with strangers INTER_40* to relate to strangers 40.2 40.2
d740 Formal relationships INTER_41* to initiate and maintain relations with subordinates, peers or superiors 41.2 41.2
d750 Informal social
relationships
INTER_42* to initiate and maintain relations with friends, neighbours, acquaintances or
colleagues
42.2 42.2
d760 Family relationships INTER_43* to initiate and maintain family relations 43.2 43.2
d770 Intimate relationships INTER_44* to initiate and maintain intimate or sexual relations 44.2 44.2
d8. Major life areas
d810 Informal education
d820 School education
d830 Higher education
F_1 Level of studies completed
F_2 In relation to your finished studies, what is your diploma degree or graduate
degree?
F_3 In the last five years, have you done any vocational training course?
G_1 In relation to education and school integration, what was your situation last
week?
d850 Remunerative
employment
E_1 Due to the onset or worsening of your disability, have you had to amend
your relationship with economic activity or your occupation?
E_5 Relation with economic activity in the past week.
E_6 Have you worked at some point as an employee or freelance worker?
E_15 Professional situation
E_20 Why did you stop working?
d860 Basic economic
transactions
d870 Economic self-sufficiency F_3a What is the monthly amount of the total income for this household?
d9. Community, social and civic life
d910 Community Life H_2_11 In the last 12 months, have you felt discriminated against on the basis of
your disability in any of the following situations? In social participation
H_2_12 In the last 12 months, have you felt discriminated against on the basis of
your disability in any of the following situations? In social relations
I_4_2 Have you had any opportunities in the last 12 months? Relating with
friends or persons who are close
d920 Recreation and leisure I_5_2 What activities do you spend most of your spare time on, and which would
you like to carry out for enjoyment or recreation that you do not already, due
to your disability? Please select the three main activities in both columns.
d930 Religion and spirituality
d940 Human rights
d950 Political life and
citizenship
H_2_7 In the last 12 months, have you felt discriminated against on the basis of
your disability in any of the following situations? - Public Administration
Where applicable, the item for difficulty involved in activities undertaken with technical or personal aid was taken as performance. Variables not marked with an
asterisk and having their content shown in italics were excluded from backcoding, either from an interim list by two authors acting in consensus, or after
reviewers’ comments and consideration by an ICF expert. Spaces left blank indicate no EDAD 2008 item was deemed appropriate for ICF coding. Domains totally
devoid of items considered valid for backcoding (d1) or represented by single EDAD 2008 items (d8,d9) were dropped from further analysis and results
As the extra question for performance was not always asked, the columns entitled “capacity” and “performance” show the number of the item from which the
information was taken.
aThis item is taken from the household instead of the disability questionnaire.
P = personal assistance,t = external technical aid,pt = personal assistance or technical aid.
When there was more than one item linked to an ICF category the meanm or the maximummax of these items was used.
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disability indices were obtained, one for capacity and the
other for performance, using the same ICF score conver-
sion procedure explained below. Domains for which
there were no questions on aid (d1, “Learning and
applying knowledge”, d7 “Interpersonal interactions and
relationships”, and, in part, d3 “Communication”, see
Table 1) were excluded from this method of deriving
performance. For items from other domains where there
was confirmation that no aid had been received, infor-
mation on capacity was used to impute the value of per-
formance, assuming that capacity equalled performance
in such cases. In the EDAD 2008, we were unable to
identify collected data on barriers, whether physical or
social, and facilitators (other than the above-mentioned
“help”) linked to disability items.
Calculation of a tentative ICF checklist-oriented individual
score
In the EDAD 2008, level of disability is rated on an ordi-
nal scale with the following four response options: no/
mild difficulty (1); moderate difficulty (2); severe diffi-
culty (3); and complete difficulty (4). In the ICF, each
response option corresponds to a percentage interval of
“Activity limitation” or “Restriction in Social Participa-
tion”, represented by the corresponding “qualifier” in
five intervals (see Table 2), e.g., severe difficulty ranges
from 50% to 95%, and complete difficulty from 96% to
100%. Hence, in order to arrive at a reasonable calcula-
tion of the mean of several ICF items, these had to be
rescaled according to their equivalent percentage values,
e.g., the response option, “severe difficulty”, was recoded
as 72.5%. To obtain a score, the mean value of any
given ICF-framed selected item was calculated, scaled
from 0% to 100% and recoded as ICF option 1 to 4,
based on the ICF percentage intervals shown in Table 2.
ICF capacity and, when available, performance indices in
single domains were thus obtained, and categorised into
four (1-4) rather than five (0-4) levels.
Score intervals were then selected as values corre-
sponding to ordinal ICF qualifiers. Qualifiers for ICF
items resulting from EDAD 2008 data were obtained by
combining the scores for the selected EDAD 2008
variables, as indicated in Table 1, where “Learning and
applying knowledge” (d1), “Major life areas” (d7) and
“Community, social and civic life” (d9) were excluded,
both for the remaining specific domains and for the glo-
bal score which lacked data from the excluded domains.
In practice, the effect of such exclusion on the method
is to render global scores rather insensitive to restric-
tions in social participation. Moreover, the fact that dis-
ability data were obtained after screening positive for at
least one of 44 disability items, means that the value 1
for no/mild difficulty described in Table 2 and denoted
as N, most frequently corresponded to “mild” difficulty,
i.e., mild disability, and for our purposes will therefore
be referred to as the “mild disability group”. Screened
negative status was denoted as SN.
Epidemiological measurements
Prevalence proportions
Prevalence proportions were calculated in the following
three different contexts for particular requirements or
purposes: a) data from the screened population, includ-
ing both the community-dwelling and institutionalised
samples, were used to describe crude prevalence of dis-
ability among the country’s population; b) the screened
community-dwelling population alone (i.e., excluding
the institutionalised sample) furnished data for age-spe-
cific and age- and sex-adjusted measurements among
the country’s population and; c) proportions in the
population that screened positive were used to describe
ICF disability patterns by ICF domain. Calculation of
age-specific or age-adjusted prevalence required exclu-
sion of the institutionalised population, due to con-
straints relating to categorical changes in age data
according to type of centre and Autonomous Region
(see Table 3). However, since the severely/completely
disabled were living in institutions, some figures selected
by centre- and age-group were occasionally included in
counts for the purposes of completeness. Prevalence fig-
ures had only two different denominators, namely: the
general -sometimes age- and sex-specific- Spanish popu-
lation; and the disabled screened positive population
Table 2 ICF categories: (a) as originally denoted and described in words, numerals, percentages and mid-point scores
for each categorical percentage-span; and (b) as backcoded in this study.
ICF (in words) ICF (in categories) ICF (in percentage terms) EDAD 2008 categories Mid-point score
No difficulty 0 0%-4% No or mild difficulty 12%
Mild difficulty 1 5%-24%.
Moderate difficulty 2 25%-49% Moderate difficulty 37%
Severe difficulty 3 50%-95% Severe difficulty 72.5%
Complete difficulty 4 96%-100% Complete difficulty 98%
Since the EDAD 2008 drew no distinction between 0 and 1, these two options were combined as 0%-24%, which matches a mid-point score of 12%
A global score was obtained for capacity measurements but not for performance. To calculate such a global score, a total of 32 variables were -not always
unequivocally- selected to build 32 ICF categories from the ICF checklist (Tables 1 and 3). Answers of inapplicable and missing values were replaced by 1 (no or
mild difficulty).
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used to describe proportions affected by different sever-
ity levels.
In view of the fact that (a) sample probability was dif-
ferent for community-dwelling and institutionalised per-
sons, with the former being tailored to provinces and
the latter to Autonomous Regions, and that (b) result
interpretability in terms of representativeness vis-à-vis
the Spanish resident population was required, EDAD
2008 weighting was systematically applied to the
numerators and denominators of the above-mentioned
prevalence. After weighting, the subsamples were found
to be accurately representative of the resident Spanish
population. Our estimate of 45,031,810 community-
dwelling and 290,506 institutionalised persons fitted well
with the data reported on the survey web page [14].
Comparison with the National Institute of Statistics’
data on the general population at 1 January 2008 [21]
for each Autonomous Region yielded numbers 1%-3%
higher than the numbers obtained by us from the
EDAD 2008 data, except for a 5% difference in the case
of Melilla and Ceuta, two relatively small cities located
in Northern Africa.
Results
Descriptive statistics for items in single disability domains
The distribution of ICF categories and percentage of
missing values in community-dwelling and institutiona-
lised persons, after the sample aged ≥6 years had been
excluded, are shown in Table 4. The sample ratio of
institutionalised to community-dwelling subject who
screened positive was 1:13. In general, missing values
were far less frequent in the institutionalised sample.
The proportions of missing values ranged from 2.3% to
43.6% for the community-dwelling sample and from 0%
to 0.6% for the institutionalised sample, except for item
d475, “Driving”, for which the proportions of missing
values were 51.7% and 72.7% in the respective samples.
Prevalence of disability by ICF capacity index
Assuming that all persons living in centres screened
positive, prevalence of disability as seen from positive
screening nation-wide (all levels included) was: 9.6%
among persons aged ≥6 years; 2.2% among persons aged
0-5 years; 9% among community-dwelling persons aged
≥6 years; and 0.7% for institutionalised persons among
the over-all population aged ≥6 years. Prevalence of
severe or complete disability as defined by ICF qualifiers
3 and 4 from capacity scores for all persons aged ≥6
years was 1.2%, with 0.9% corresponding to those living
in the community and 0.3% to institutionalised persons
using the same population denominator. In other words,
approximately one out of four severely/completely dis-
abled persons was institutionalised.
Figures 1a-d depict the age- and sex-specific preva-
lence of disability according to our ICF capacity index
among the ≥6-year-old Spanish population separately by
residential status, i.e., the community-dwelling and insti-
tutionalised components. It should be noted that
screened negative persons are included in the denomi-
nators only, and that percentages do not therefore add
up to 100. Age-specific disability prevalence among
community-dwelling persons, Figures 1a and 1b,
increased with age in men and women alike but was
systematically higher among the latter, with crude pre-
valence of 7.3% in men and 10.6% in women. With
regard to institutionalised persons, Figures 1c and 1d, in
practice the proportion of institutionalised disabled per-
sons per 100 inhabitants was restricted to the popula-
tion aged < 65 years and ≥65 years and was
approximately twice as high among women, particularly
in the moderate and severely disabled levels. The crude
prevalence of institutionalised disabled persons aged ≥65
years was 0.6% for men and 0.9% for women. The 0-5
year age group registered a 2.2% prevalence of disability.
The paucity of information on type of limitation present
Table 3 Different age groupings (1, 2 and 3) used in the sample of institutionalised persons, and the grouping used in
this study to merge the information on age
Grouping 1
Age years
n Grouping 2
Age years
n Grouping 3
Age years
n Grouping used
Age years
n
6-64 20879 6-79 13084 6-64 23446 6-64 44325
65-79 48007 > 65 9165 ≥65 227599
≥80 144805 ≥80 25622
NS 76815 NS 251800 NS 257895 NS 18582
NS = Not Specified
The groups differ by Autonomous Region and type of centre (type 1: home or residential centres, type 2 psychiatric or geriatric hospitals or centres for disabled
persons), encompassing:
Grouping 1: type-1 centres and Autonomous Regions 1, 2, 7, 8, 9, 10, 11, 13, 16 or type-2 centres and Autonomous Regions 1, 5, 9.
Grouping 2: Type-1 centres and Autonomous Regions 4, 5, 6, 7, 12, 14, 15, 17.
Grouping 3: Type-2 centres and Autonomous Regions 2, 3, 6, 7, 8, 11, 12, 13, 14, 15, 16, 17.
Column “n” shows the number of persons in each age-group after the cases had been weighted. The age groups used were 6-64 and over-64 years (Grouping 3).
Consequently, the 6-79 age group in grouping 2 and all cases with no information whatsoever on age are set to “missing”.
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meant that the ICF disability score could not be calcu-
lated for the 0-5 year age group.
Figure 2 depicts the prevalence of ICF disability in the
community-dwelling population (prevalence equals rec-
tangle height), as well as the number of affected indivi-
duals of both sexes in each age category (numbers are
equivalent to rectangle surface). Prevalence of disability
increased with age, with the number of disabled persons
decreasing among the very old. The highest prevalence
corresponded to the moderately disabled with 920,310
persons, with the estimated total number of severely/
completely disabled persons being 380,838. The highest
numbers of severely/completely affected individuals
were those aged ≥70 years. Numbers increased with age,
i.e., rising from 26904 persons aged 70-74 years to
44137 persons aged 75-79 years, 61868 persons aged 80-
84 years and 67125 persons aged 85-89 years, and then
subsequently decreased to 62329 persons aged 90-105
years.
Figure 3 depicts the prevalence of ICF capacity, both
overall and for seven different ICF domains, as seen
from the screened positive, community-dwelling popula-
tion for each sex. Prevalence patterns varied, with the
highest prevalence of severe/complete disability levels
being 1.9% in “Mobility”, 2.1% in “Self-care” and 4.1% in
“Domestic life” for women (and 1%, 1.1% and 1.8%
Table 4 Percentages for ICF-Categories (No/mild difficulty, N; moderate difficulty, M; severe difficulty, S; complete
difficulty, C) and subscores for each of the seven domains, as well as missing values (MV) in percentages.
Community-dwelling persons Institutionalised persons
ICF ICF title N M S C MV N M S C MV
d2 General tasks and demands 91.37 0.89 3.49 4.24 7.96 59.9 6.15 16.28 17.67 0
d210 Undertaking a single task 90.86 2.00 2.54 4.60 7.41 68.96 5.10 7.54 18.41 0
d220 Undertaking multiple tasks 85.73 3.14 3.63 7.50 2.32 54.59 7.34 8.83 29.24 0
d3 Communication 94.22 1.08 3.26 1.43 13.54 60.94 12.75 19.26 7.05 0.16
d310 Communicating with – receiving – spoken messages 89.45 4.08 4.20 2.26 9.07 67.53 8.20 14.24 10.04 0.02
d315 Communicating with – receiving – non-verbal messages 92.38 1.79 2.76 3.07 11.68 68.22 5.01 10.49 16.27 0.03
d330 Speaking 88.26 4.49 4.35 2.90 7.82 66.72 7.44 13.48 12.37 0.04
d350 Conversation 88.27 3.86 4.10 3.78 7.94 61.97 7.37 13.07 17.59 0.08
d4 Mobility 89.58 4.06 4.78 1.57 60.27 20.23 31.85 39.78 8.14 72.76
d430 Lifting and carrying objects 48.6 17.14 18.71 15.55 28.43 52.28 9.09 10.10 28.53 0.02
d440 Fine hand use 63.78 12.73 12.74 10.75 43.61 64.76 7.54 9.80 17.89 0.02
d450 Walking 60.38 7.27 21.38 10.97 40.73 35.76 12.98 29.06 22.21 0.25
d470 Using transportation 45.45 13.82 18.40 22.33 23.80 21.71 14.89 15.13 48.27 0.12
d475 Driving 75.55 3.90 2.97 17.58 51.65 23.47 1.79 4.52 70.22 72.66
d5 Self-care 96.39 2.42 0.76 0.44 45.00 21.16 25.23 31.75 21.86 96.67
d510 Washing oneself 61.29 10.77 11.81 16.13 14.08 29.14 19.22 13.85 37.79 0.04
d520 Caring for body parts 62.26 9.59 11.01 17.13 15.19 28.66 17.69 13.59 40.06 0.04
d530 Toileting 96.76 2.10 0.37 0.77 44.86 37.94 17.07 11.14 33.85 96.65
d540 Dressing 66.64 10.56 10.20 12.60 20.47 45.68 13.69 11.24 29.38 0
d570 Looking after one’s health 76.71 3.46 4.26 15.58 30.79 32.07 13.03 11.60 43.30 0.46
d6 Domestic life 61.37 5.17 10.70 22.76 25.63 19.97 10.25 16.60 53.17 0.62
d620 Acquisition of goods and services 47.81 10.74 12.21 29.25 5.52 22.60 9.91 8.08 59.41 0.29
d630 Preparation of meals 60.00 7.29 7.24 25.46 22.85 22.39 8.74 7.10 61.78 0.15
d640 Doing housework 51.01 10.23 12.13 26.63 10.73 23.44 9.09 7.28 60.19 0.19
d7 Interpersonal inter-actions and relationships 95.16 0.68 2.60 1.56 11.50 45.14 29.49 18.69 6.68 1.05
d710 Basic interpersonal interactions 92.63 2.41 2.88 2.09 8.94 75.02 5.72 9.37 9.89 0.04
d730 Relating with strangers 88.55 2.4 3.36 5.68 5.16 60.16 6.52 10.11 23.21 0.10
d740 Formal relationships 90.49 1.82 2.37 5.32 6.95 75.61 6.21 7.90 10.28 0.11
d750 Informal social relationships 90.17 2.38 3.15 4.29 6.67 69.41 5.87 9.02 15.69 0.04
d760 Family relationships 90.04 1.82 2.8 5.34 6.54 75.43 5.74 8.61 10.21 0.17
d770 Intimate relationships 88.36 1.51 2.37 7.77 4.82 38.83 4.81 9.20 47.16 0.63
All numbers were calculated using individually weighted data
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respectively for men). While the high prevalence pat-
terns were similar across the sexes, differences between
the sexes in magnitude were nevertheless present. In
terms of total and “Mobility”, “Self-care” and “Domestic
life” domain scores, prevalence was higher among
women than men. In contrast, differences between sexes
were not substantial for prevalence of severe/complete
disability in domains with lower prevalences, such as
“General tasks and demands”, “Communication” and
“Interpersonal interactions and relationships”.
Capacity and performance patterns: ICF index by specific
domain within single group by total ICF score
The distribution by disability level for capacity (left) and
performance (right) subscores in the above-mentioned
available ICF domains for groups of positively screened
● ● ●
●
●
●
●
●
●
●
● ●
0
10
20
30
40
x
P
re
va
le
nc
e 
in
 %
6−
16
17
−2
4
25
−3
4
35
−4
4
45
−5
4
55
−6
4
65
−6
9
70
−7
4
75
−7
9
80
−8
4
85
−8
9
90
−1
05
Age
men
●
Capacity Score
no/mild difficulty
moderate difficulty
severe difficulty
complete difficulty
● ● ●
●
●
●
●
●
●
● ●
●
0
10
20
30
40
x
P
re
va
le
nc
e 
in
 %
6−
16
17
−2
4
25
−3
4
35
−4
4
45
−5
4
55
−6
4
65
−6
9
70
−7
4
75
−7
9
80
−8
4
85
−8
9
90
−1
05
Age
women
● ● ● ● ● ●
● ● ● ● ● ●
0.
0
0.
5
1.
0
1.
5
2.
0
P
re
va
le
nc
e 
in
 %
6−64 >65Age
men
● ● ● ● ● ●
● ● ● ● ● ●
0.
0
0.
5
1.
0
1.
5
2.
0
P
re
va
le
nc
e 
in
 %
6−64 >65Age
women
Figure 1 Age- and sex-specific prevalence for four levels of total ICF disability score for capacity, separated into two components
aged ≥6 years, i.e., community-dwelling screened positive residents (top) and institutionalised persons (bottom). Denominators for
community-dwelling persons were obtained from the screened sample (community-dwelling persons); denominators for prevalence counts of
institutionalised persons correspond to community-dwelling and institutionalised persons.
Maierhofer et al. BMC Public Health 2011, 11:897
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persons with four different total ICF capacity levels (N,M,
S,C) is depicted in Figure 4. The most remarkable feature,
more clearly visible in the case of capacity (left), was to be
seen for groups of moderately disabled subjects in terms
of total ICF score (M groups), in that these registered con-
siderable proportions of persons with severe or complete
capacity subscores, particularly in “Domestic life”, 80%,
“Mobility”, 31.3% and “Self-care”, 34.5%, with severe dis-
ability in these domains thus being relatively masked by
the total ICF score. A second aspect of differences between
capacity (left) and performance (right) patterns, once again
more clearly visible for the moderately disabled by total
ICF score, was the relative invariance in capacity versus
performance in “General tasks and demands”. In contrast,
performance (right) was markedly better than capacity
(left), as reflected by the lower proportions of severe or
complete disability in the “Mobility”, “Self-care” and
“Domestic life” domains.
● ● ● ● ●
SN
N
M
S
C
SN
N
M
S
C
scorescore
6í
16
17
í2
4
25
í3
4
35
í4
4
45
í5
4
55
í6
4
65
í6
9
70
í7
4
75
í7
9
80
í8
4
85
í8
9
90
í1
05age
Figure 2 Age-specific prevalence of different ICF disability levels, including disability-free/screened negative (SN) persons, as well as
number of persons affected in each age and ICF group. N = no/mild difficulty, M = moderate difficulty, S = severe difficulty, C = complete
difficulty.
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Discussion
The EDAD 2008 is not only the most important data-
base on disability among the Spanish population, but is
arguably also one of the most complete, periodic,
national population approaches to studying disability
worldwide. The EDAD 2008 incorporated important
contributions, such as data for institutionalised persons.
Major differences between the EDAD 2008 and previous
disability surveys in Spain pertain to the former’s
additional, newly designated target of providing informa-
tion on functional dependency in order to support plan-
ning and funding of the Spanish dependency system. As
a first step, this study sought to link the EDAD 2008 to
an analysis of functional dependency, by ICF Checklist
backcoding and score rescaling of EDAD 2008 items
restricted to the Activity and Participation domains. An
important limitation of this exercise is asymmetry, in
that it suffers from a lack of crosswalking between
Total
P
re
va
le
nc
e 
in
 %
0
5
10
N M S C
Men
Women
5.1
6.6
1.5
2.9
0.6 1.1 0 0
●
General tasks
P
re
va
le
nc
e 
in
 %
0
5
10
N M S C
6.4
9.3
0.2 0.3 0.4 0.6 0.2 0.5
Communication
P
re
va
le
nc
e 
in
 %
0
5
10
N M S C
6.3
9.6
0.5 0.5 0.3 0.4 0.1 0.2
Mobility
P
re
va
le
nc
e 
in
 %
0
5
10
N M S C
4.7
5.7
1.6
3
0.9
1.9
0.1 0
Self care
P
re
va
le
nc
e 
in
 %
0
5
10
N M S C
5.1
6.6
1
1.8
0.8
1.5
0.3 0.6
Domestic life
P
re
va
le
nc
e 
in
 %
0
5
10
N M S C
4.6 4.4
0.8
2.1
0.7
2.1
1.1
1.9
Interactions
P
re
va
le
nc
e 
in
 %
0
5
10
N M S C
6.2
9.4
0.5 0.5 0.4 0.6 0.1 0.1
Figure 3 Crude, sex- and domain-specific prevalence of different ICF severity scores among the general population from screened
positive persons. Percentages do not add up to 100% due to screened negative persons. N = no/mild difficulty, M = moderate difficulty, S =
severe difficulty, C = complete difficulty.
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EDAD 2008 variables and Body Structures and Func-
tions, as well as a neglect of aspects potentially related
to ICF contextual factors in general and to Environmen-
tal Factors in particular.
Results show that, in practice, ICF domains such as
“Learning and applying knowledge”, “Major life areas”
and “Community, social and civic life” were disregarded,
and others, such as “General tasks and demands”, were
not appropriately covered by posing just a couple of
questions. The frequent NDS bias towards activity-level
data, described above in the case of United Nations
efforts [5], permeates the EDAD 2008. Hence, ICF
domain restriction, score rescaling and exclusion of
institutionalised persons in age-specific counts may ser-
iously limit the interpretability and international com-
parability of prevalence figures in respect of both
capacity and performance, whether for single ICF
domains or individual total ICF score indices. In addi-
tion, much remains to be improved to ensure a homo-
geneous and complete data-contribution from
institutionalised persons in the country’s different
Autonomous Regions (Comunidades Autónomas), which
●Capacity subscores
N: no/mild difficulty
M: moderate difficulty
S: severe difficulty
C: complete difficulty
●Performance Subscores
N: no/mild difficulty
M: moderate difficulty
S: severe difficulty
C: complete difficulty
General tasks
0
0.
5
1
N M S C
General tasks
0
0.
5
1
N M S C
Communication
0
0.
5
1
N M S C
●
Mobility
0
0.
5
1
N M S C
Mobility
0
0.
5
1
N M S C
Self care
0
0.
5
1
N M S C
Self care
0
0.
5
1
N M S C
Domestic life
0
0.
5
1
N M S C
Domestic life
0
0.
5
1
N M S C
Interactions
0
0.
5
1
N M S C
Figure 4 Prevalence of domain- and qualifier-specific disability (by capacity or performance) among subgroups defined by total ICF
capacity scores, for community-dwelling residents aged ≥6 years. N = no/mild difficulty, M = moderate difficulty, S = severe difficulty, C =
complete difficulty.
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currently constitute the main EDAD 2008 stakeholders
in terms of health and social services.
Once the most relevant limitations have thus been
defined, our results can be said to afford a structured,
albeit non-validated, view of the prevalence of ICF dis-
ability in Spain in 2008, with approximately 12/1000
severely/completely disabled and 24/1000 moderately
disabled persons, and the latter registering relatively
high proportions of severe/complete disability in the fol-
lowing subscores: “Self-care”, 1/3; “Mobility”, 3/10; and
“Domestic life”, 8/10. These proportions were consider-
ably reduced, though not eliminated, by personal or
technical aid.
Interpretation and analysis of results may be better
suited to comparisons with other ICF measurements in
populations. In a Turkish study on the elderly popula-
tion, Donmetz et al in 2005 [22] reported median scores
for persons found to give at least one positive answer in
the WHODAS-2. The fact that we cannot compare our
results from ICF prevalence measurements of similar
ICF categories obtained from total scores or for specific
domains illustrates the implications of application or
neglect of epidemiological principles and of descriptive
and analytical purposes in population research.
Reported age-specific prevalence of ICF moderate dis-
ability among the very old in Spain [23] is remarkably
similar to figures cited here for community-dwelling
residents, e.g., 10.61% for men and 16.47% for women in
the 80-84 age group compared to the corresponding
values of 10.2% for men and 16.9% for women shown in
Figure 1. Despite the fact that the sample in Virués et
al’s study was certainly not geographically representative
of the Spanish population, the similarities are nonethe-
less striking, suggesting that the external validity of the
risk factors of ICF severe/complete disability identified
by this study for the Spanish population is high [Virués
Ortega J et al. Medical, Environmental and Personal
Factors of Disability in the Elderly People in Spain: A
Screening Survey based on the International Classifica-
tion of Functioning (Gaceta Sanitaria 2011, in press)].
Assuming that our figures are accurate, the numbers
obtained by us for the severe or complete disability
levels would allow the numbers of severely/extremely
disabled persons in Spain to be estimated for the first
time. These figures, namely, 135,506 men and 245,331
women, constitute figures that are remarkably lower and
easier to interpret than those reported in 1999 for per-
sons with, say, several disabilities [11] but may not be
comparable. Prevalence of severe disability among 85-89
year-old community-dwelling residents in Gloucester
UK, measured by a postal survey using a validated inde-
pendence scale, was 13.4% for men and 20.9% for
women, approximately double that found for severe/
complete capacity in our study [24]. Similar differences
were seen in other sex- and age-groups. It is possible
that, despite limited comparability, our figures constitute
undercounts, an effect reinforced by the impact of
assigning 1 to items where data were missing, something
that particularly affected men in “Domestic life” and
women in outdoor “Mobility”.
Thanks to the large sample size, the value our results
is almost unique when it comes to describing disability
patterns by ICF domain. The higher prevalence regis-
tered for women and for “Domestic Life”, “Mobility”
and “Self-care” replicate similar patterns observed for
extremely aged Spanish [23]; and for elderly Turkish
subjects, with mean scores when disabled of 50.5, 40.6
and 34.2 respectively, and a total WHODAS-2 score of
23.0 [22].
The fact that the above-mentioned domains with
higher prevalence correspond to domains in which preva-
lence of disability decreases when measured by perfor-
mance, i.e., with personal or technical aid, fits expected
changes expected from the ICF framework. The consid-
erable modification of patterns in the moderately dis-
abled group might indicate that such groups constitute a
target for provision of services, in cases where severe/
extreme disability can be reduced by personal or techni-
cal aid. The large size of this group renders it even more
relevant for policy-making and points to a large popula-
tion segment of the Spanish population which, in addi-
tion to the approximately 500,000 severely/completely
disabled, encompasses more than 50% of the 1,000,000
persons with ICF moderate disability who could poten-
tially benefit from personal aid if available. Since the
EDAD 2008 furnishes data on time devoted by caregivers
and an assessment of the shortfall, Figure 4 may provide
some clues for estimating the need -both met and
unmet- for help from other persons, and for building an
index of such help in terms of work time, e.g., hours/
week. Unfortunately, the lack of availability of data for
domains such as social participation, limits the usefulness
of the EDAD 2008 when it comes to estimating the need
for help to improve social participation in, e.g., work, lei-
sure or economy. This domain may be particularly rele-
vant for persons affected by non-somatic ailments, such
as psychiatric patients whose disability may have been
underrepresented in the EDAD 2008 due to formulation,
inasmuch as it documents occupational status but not
the barriers encountered in overcoming restricted access
to work. In brief, it would appear that, taking ICF cate-
gories as the point of departure, the EDAD 2008 may
provide a basis for estimating the prevalence of need for
personal help, with it being more difficult to address the
need for social support required to improve social parti-
cipation in, e.g., work, leisure or economy.
Focusing prevalence on disease status, the required
epidemiological dimension of services research is well
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recognised. Nevertheless, an ICF-based approach to the
design of National Disability Surveys might be difficult
to reconcile with usability of an ICF “which does not
classify people” despite “ICF classifies health-related
states” (quotation marked fragments obtained from ICF
ref 1, page 8). Our results may point towards a role for
an epidemiological approach which reinforces the con-
cept of functional dependence, by minimising the visua-
lisation of severe mental disorders with sparse
limitations of basic ADL and their need of social sup-
port. A description of the differences between functional
dependency and disability, and the particularities of the
Spanish approach to dependency in the context of the
ICF has recently been published [25]. The need for brid-
ging and knowledge transfer in the field of disabilities
and ageing, possibly related to certain content discre-
pancies between the ICF and EDAD 2008, has been
highlighted [3]. It is not known whether differences
between the ICF and EDAD 2008 evidenced in Table 1
and the limitations of our approach rely on the lack of
bridging between the Spanish group who drew up the
survey and the existing international ICF-WHO groups
(e.g., ICF/FDRG, ICF Spanish Network on Disabilities,
and the above-mentioned experiences of the Washing-
ton City Group and Ireland) or on deeper ICF con-
straints discussed by Salvador-Carulla and others [25].
To sum up, the Spanish EDAD 2008 represents a
powerful initiative and considerable limitations in terms
of applying the ICF to questionnaire design and epide-
miological analysis of disability. However, the EDAD
2008 can be said to be a useful tool for describing the
prevalence of disability and, potentially, for estimating
functional dependence for planning aid and services,
taking social and geographical differences into account.
Approximately 500,000 to 1,000,000 persons present
with ICF levels of severe/complete and moderate disabil-
ity, respectively. In terms of magnitude, such figures fit
reported age-specific prevalence data for disability levels
obtained from the WHODAS-2 for the very old in
Spain, and match the higher difficulty pattern in mobi-
lity, domestic life and self-care domains.
Financial support
This study was partially supported by the Consortium
for Biomedical Research in Neurodegenerative Diseases
(Centro de Investigación Biomédica en Red sobre Enfer-
medades Neurodegenerativas - CIBERNED), Spanish
Health Research Fund (Fondo de Investigaciones Sanitar-
ias) project PI06/1098 and Farasdués Foundation.
Acknowledgements
The authors would like to acknowledge the support received from Alarcos
Cieza and Cornelia Oberhauser, at the Institute for Health & Rehabilitation
Sciences, Biopsychosocial Health Research Unit, Ludwig-Maximilians
University, Munich, Germany, for having inspired this manuscript, based on
their initial analyses of the Spanish 1999 and 2008 surveys, which were
presented at the conference, “Aplicación en España de la Clasificación
Internacional del Funcionamiento, la Discapacidad y la Salud (CIF): Presente
y Futuro” on May 30, 2010 in Madrid. Thanks must also go to Michael
Benedict for his help with the review and revision of the English-language
version of the manuscript.
Competing interests
The authors declare that they have no competing interests.
Received: 9 June 2011 Accepted: 28 November 2011
Published: 28 November 2011
References
1. World Health Organization: World Health Organization International
Classification of Functioning, Disability and Health. 2001.
2. Cieza A, Ewert T, Ustun TB, Chatterji S, Kostanjsek N, Stucki G: Development
of ICF core sets for patients with chronic conditions. J Rehabil Med 2004,
44(Suppl):9-11.
3. McDaid D, Cieza A, Gomez AR: Bridging knowledge: reflections on
crossing the boundaries between long-term care and support. Int J
Integr Care 2009, 9:e60.
4. Kostanjsek N: Use of The International Classification of Functioning,
Disability and Health (ICF) as a conceptual framework and common
language for disability statistics and health information systems. BMC
Public Health 2011, 11(Suppl 4):S3.
5. Swanson G, Carrothers L, Mulhorn KA: Comparing disability survey
questions in five countries: a study using ICF to guide comparisons.
Disabil Rehabil 2003, 25(11-12):665-675.
6. Mulhorn KA, Threats TT: Speech, hearing, and communication across five
national disability surveys: results of a DISTAB study using the ICF to
compare prevalence patterns. Int J Speech Lang Pathol 2008, 10(1-2):61-71.
7. Madans JH, Loeb ME, Altman BM: Measuring disability and monitoring
the UN convention on the rights of persons with disabilities: the work
of the Washington group on disability statistics. BMC Public Health 2011,
11(Suppl 4):S4.
8. Good A. Using the ICF in Ireland. BMC Public Health 2011, 11(Suppl 4):S5.
9. Nieuwenhuijsen ER: On health, ability and activity: comments on some
basic notions in the ICF commentary. Disabil Rehabil 2006,
28(23):1477-1479.
10. Stineman MG, Ross RN, Maislin G: Functional status measures for
integrating medical and social care. Int J Integr Care 2005, 5:e07.
11. Albarrán-Lozano I, Alonso-González P, Fajardo-Caldera MA: Valoración
global de la discapacidad. Propuesta de un índice y su aplicación a la
población española recogida en la EDDES. Estudios de Economía Aplicada
2007, 25:523-549.
12. La Parra D, Masanet E: [Comparison of time spent on unpaid work as
measured by the National Health Survey and the time use survey]. Gac
Sanit 2011, 25(1):68-71.
13. Instituto Nacional de Estadística: Survey on Disabilities, Impairments and
Health Status 1999. Madrid [http://www.ine.es/jaxi/menu%20do?
type=pcaxis&path=%2Ft15/p418&file=inebase&L=1], Access date: 3 May
2010.
14. Instituto Nacional de Estadística: Survey on Disability, Personal Autonomy
and Dependency situations 2008. Madrid [http://www.ine.es/jaxi/menu%
20do?type=pcaxis&path=%2Ft15/p418&file=inebase&L=1], Access date: 3
May 2010.
15. Abellán A: La discapacidad en España. Rev Mult Gerontol 2001, 11:35-37.
16. Instituto Nacional de Estadística: Disabilities, Independence and
Dependency Situations Survey (DIDSS). Methodology Madrid. Spain; 2010
[http://www.ine.es/en/metodologia/t15/t1530418_en.pdf], Access date: 2
May 2010.
17. Instituto Nacional de Estadística: Encuesta sobre Discapacidad, Autonomía
personal y Situaciones de Dependencia (EDAD). Metodología Madrid.
Spain; 2010 [http://www.ine.es/metodologia/t15/t1530418.pdf], Access date:
2 May 2010.
18. Instituto Nacional de Estadística: Cuestionarios de la Encuesta sobre
Discapacidad, Autonomía personal y Situaciones de Dependencia 2008.
Madrid. Spain; 2010 [http://www.ine.es/daco/daco42/discapa/cues07.htm],
Access date: 3 May 2010.
Maierhofer et al. BMC Public Health 2011, 11:897
http://www.biomedcentral.com/1471-2458/11/897
Page 14 of 15
19. Instituto Nacional de Estadística: Questionnaires of the Survey on
Disability, Personal Autonomy and Dependency situations 2008. Madrid.
Spain;[http://www.ine.es/en/daco/daco42/discapa/cues07_en.htm].
20. World Health Organization: ICF checklist version 2.1A. Geneva, World Health
Organization 2009.
21. Instituto Nacional de Estadística. Padrón municipal: Cifras oficiales de
población desde 1996. Data as at 1 January 2008 for Autonomous Regions
and sex [http://www.ine.es/jaxi/menu%20do?type=pcaxis&path=%2Ft20%
2Fe260&file=inebase&L=], Access date: 2 May 2010.
22. Donmez L, Gokkoca Z, Dedeoglu N: Disability and its effects on quality of
life among older people living in Antalya city center, Turkey. Arch
Gerontol Geriatr 2005, 40(2):213-223.
23. Virues-Ortega J, de Pedro-Cuesta J, Seijo-Martinez M, Saz P, Sanchez-
Sanchez F, Rojo-Perez F, et al: Prevalence of disability in a composite >/=
75 year-old population in Spain: a screening survey based on the
International Classification of Functioning. BMC Public Health 2011, 11:176.
24. Donald IP, Foy C, Jagger C: Trends in disability prevalence over 10 years
in older people living in Gloucestershire. Age Ageing 2010, 39(3):337-342.
25. Salvador-Carulla L, Garcia-Gutierrez C: The WHO construct of health-
related functioning (HrF) and its implications for health policy. BMC
Public Health 2011, 11(Suppl 4):S9.
Pre-publication history
The pre-publication history for this paper can be accessed here:
http://www.biomedcentral.com/1471-2458/11/897/prepub
doi:10.1186/1471-2458-11-897
Cite this article as: Maierhofer et al.: Prevalence and features of ICF-
disability in Spain as captured by the 2008 National Disability Survey.
BMC Public Health 2011 11:897.
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