Methodology 

In recent years there has been an increasing demand for information about disability and dependence, and which has specified the number, characteristics and situation of people with a disability. In a context of population change, caused by an increase in longevity and the ageing of the population, social and political institutions have to adjust and make more accurate their objectives in order to respond to the increasing demand for social protection.

Life expectancy has increased thanks to medical progress and the welfare states. This indicator is relevant per se, but so is life expectancy free of disabilities, which tells us about the autonomy of the older population. On the basis of specific disability rates by age we can constrict these indicators.

The needs of people with a disability vary depending on social changes and the environment. In this regard, the presence of women in employment and new family structures are questioning the traditional support networks for people in dependent situations, and are leading to greater pressure on the social care system.

The disability surveys conducted in Spain over three editions (1986, 1999 and 2008) have provided a standard in the global understanding of this situation. It was not until the edition of 1999 and especially the current one, that there was any accurate definition of the disabilities and difficulties that lead certain activities of daily living to cause dependence. It therefore obtained a global vision of the needs for help required by people living in these dependent situations.

The Disabilities, Impairments and state of health survey (EDDES-99), conducted in 1999 by the INE set important standards in the white book on the care for people in dependent situations in Spain. This was the basis for the development of the Law to promote personal autonomy and care for people in dependent situations (LAAD) that was passed in December 2006. The LAAD is configured as a new mode of social protection and broadens and complements the protective action of the State and the Social Security System. Its implementation is being undertaken progressively between 2007 and 2015.

The survey of disability, personal autonomy and dependent situations, 2008 ( EDAD2008) was conducted by the INE, and Idescat has extended the results for Catalonia, the main objective being to obtain statistical information on disability and dependence.

This statistical operation is included in the Annual programme of statistical actions 2011 (Decree 289/2011, March), and previous editions, and is produced by means of state operated statistical files. The EDAD2008 is based on the experience of the previous Disabilities, impairments and state of health survey made in 1999, adapted to the current social and demographic conditions and the philosophy of the new International classification of functioning, disability and health (CIF).

Idescat publishes results on the number of people with a disability that reside in Catalonia in family dwellings, characteristics of these disabilities and the impairments they have caused, as well as the relations between these people and employment and education, the characteristics of carers, and social, health and economic benefits.

In population censuses in different years (1950, 1960, 1970, 1981 and 2001) questions have been introduced about the incidence of disability among the population, but the sufficient quality has not been attained. For this reason, the INE opted to undertake two disability surveys, in the years 1986 and 1999, and now again in 2008.

In 1986, the INE in collaboration with INSERSO (now IMSERSO) undertook the first Survey on disabilities, impairments and handicaps (EDDM) following the International classification of impairments, disabilities, and handicaps (CIDDM) produced by the WHO. This classification was the first to establish an official conceptual framework for disability with a common and universal language. Thirteen years later, in 1999, the INE went into collaboration with IMSERSO and the ONCE foundation, to produce the second Survey on disabilities, impairments and state of health (EDDES-99) and which included a number of major improvements that prevented direct compatibility between them.

The main objective of the Survey of disability, personal autonomy and dependent situations 2008 (hereinafter EDAD2008) is to cater for the demand for information to guide the promotion of personal autonomy and the prevention of dependent situations among people in our society. The objective of the EDAD2008 is to estimate the number of people resident in family dwellings, and also in certain collective establishments where people have some disability. The operative objectives are the estimation of the number, characteristics and situations of people with a disability. In this edition, the gender dimension has been incorporated through relevant variables in the areas of disability such as the relation with economic activity, education, carers, benefits, family networks, among others.

The main objectives are as follows:

1. Estimate the number of people with a disability that reside in Catalonia in family dwellings, through EDAD2008 addressed at dwellings (EDAD-h) and certain collective establishments, and EDAD2008 addressed at certain centres (EDAD-c), and their geographical distribution.
2. Find out the limitations on activity and restrictions in participation in situations of everyday life of people with disabilities, and also the level of severity of these limitations.
3. Find out the characteristics of people that have some disability and are in a situation of dependence.
4. Identify the different types of impairment causing these limitations.
5. Find out the causes that have led to these impairments.
6. Evaluate the equal opportunities / discrimination faced by people with a disability in employment, education, leisure, mobility, etc.
7. Identify the needs and demands for care of disabled people, and also the care they receive and its characteristics. Find out about the use of technical assistance, special adaptations (at home, at work...), personal care, etc.
8. Make an analysis of disability from a gender perspective.

The conceptual framework for the disability surveys has been the International classification of functioning, disability and health (CIF) published by the World Health Organisation (WHO) in 2001. This classification considers disability to form part of impairments, limitations on activity and restrictions on participation. It also incorporates environmental factors such as the physical, social and attitudinal aspects in the way people live and conduct their lives.

The main objectives of this classification are to provide a common and standardised language, as a conceptual framework for describing health and those who are related with health. In other words, the ICF has gone from being a classification of the consequences of illnesses to a classification of components of health.

The ICF includes in the global concept of disability the set of impairments, limitations on activity and restrictions on participation. Nevertheless, the same Classification signals that it is difficult to distinguish between "activities" and "participation" and, analogically, between "individual" and "collective". Therefore, it provides a single list of activities and participation, and leaves it up to the person to decide between activity and participation, depending on their own operative criteria.

The application of this classification, however, presents a series of methodological difficulties for which solutions have been found.

1. The study begins with the limitations on activity, in other words, disabilities, to make sure that the language is accessible to interviewers and interviewees.
2. Limitation on activity (disability) is understood to mean all serious limitation on everyday activities that have an effect or are expected to have an effect for at least a year, and that lead to some kind of impairment. However, some disabilities are explored that do not lead to a clearly delimited impairment, but that rather are the result of the degenerative processes that are decidedly influenced by a person's age.
3. Activities have been delimited for research that is basic and necessary to everyday life.
4. Disabilities can not be given in isolation, in other words, one person can have two or more disabilities that may be independent to each other or that could have their origin in the same impairment. All disabilities affecting each person are collected, whether or not they are independent from each other.
5. It must be determined from when a disability becomes the object of study, as there are apparently relevant disabilities that do not have any major effect on a person's activity and vice versa. All disabilities perceived by the population have been collected; therefore, if a person feels their activity suffers important limitations, this will be collected.
6. It has been determined when a disability is the object of study depending on permanence over time, as sometimes a passing limitation can be overcome. A limitation considered long term is when its nature or the time it has been present suggests it is such, or when it is expected to last a year or more.
7. Many limitations can stop being so with the help of some instrument or with the supervision of another person. The study investigates all disabilities a person can have even though they can by overcome with the help of an external technique or the aid or supervision of somebody else. Those disabilities considered to have been overcome with external techniques included crutches, wheelchairs, false members, hearing aids, oxygen, catharsis, among others. However, those not considered overcome are those that use internal aid (pacemakers, intraocular cataract lenses, artificial knee joints, artificial heart valves, etc.).
8. As for population areas, two age groups were established. The first is infants from 0 to 5 years and the second is people aged 6 and above. To understand the analysis of the data obtained better, this second group has been broken into two subgroups, people aged 6 to 64 years and people aged 65 years and more, thus attending to different needs.

In summary, disabilities are understood to be an important limitation of everyday activities that affect or are expected to affect the sufferer for at least one year and which originate from an impairment that has not been overcome using a technical aid or with the aid or supervision of somebody else.

The variables that are the object of study are:

• Disabilities in people aged 6 and more years and limitations on minors from 0 to 5 years.
• Characteristics of disabilities: severity, technical aid and personal assistance, impairments (this study only investigates those impairments that have a limitation on a person's activity). Among the disabilities being investigated are those related with activities of daily living that are taken into account to recognise the right to assistance as granted by law. The survey, even though it does not provide the number of dependent people in accordance with the criteria of the law, does establish a bridge between subjective perception and objective measurement of the phenomenon.
• People with a disability with employment and education; characteristics of carers; social, health and economic benefits.

The variables of classification are: age, sex, parental relations (with the person of reference in the dwelling and the people that have some disability), country of birth, level of studies obtained, disability certificate (≥33%), relation with economic activity, professional situation, occupation, province of residence.

4.1. Areas of research

• Population scope

  The survey is aimed at all dwellings and people residing in main family dwellings.

• Geographic scope

  The survey is aimed at all territory in Spain, and geographical representativeness is on a provincial level.

• Time scope

  The data collection period was between November 2007 and February 2008.

4.2. 2. Sample design

The sampling technique used was two-staged stratified sampling. In the first stage, the units were the existing census sections as on April 1, 2007, and in the second they are the relation with the main family dwellings of each of the sections selected for the sample and that have been researched in all dwellings in which there are habitual residents. The stratification criterion applied is the size of the municipality to which the section pertains. Each province is represented by an independent sample to provide data with this level of disaggregation.

The sample size on a state level is 93,325 dwellings distributed into 3,773 census sections. In Catalonia, this size is 8,723 dwellings, distributed into 392 census sections, which leads to an effective sample of 24,281 people, of which 1,923 make up the population between 0 and 5 years with a disability, and 22,358 people make up the population of 6 and more years with a disability. To fix the sample between provinces we assigned a uniform part and another proportional part of the size of the sample, taking into consideration the estimation of the number of people with a disability obtained in the last survey.

Table of distribution of strata of sample sections:

The sections have been selected within each stratum with a probability proportional to their size. The dwellings, in each section, with the same probability via random start systematic sampling. This procedure provides auto weighted samples for each stratum.

Estimators have been used by which weighting techniques are applied in order to balance the distribution of the sample with the distribution of the population known through extreme sources. The populations of reference are obtained from the estimations in the current EPOBA population made by the INE resident in family dwellings on January 2008.

4.3. 3. Phases of the survey

Having defined the concept of disability and established the criteria for the disabilities we are interested in detecting, the proposal was to use the EDAD-h in two phases, with their corresponding features: a questionnaire for the household, two individual questionnaires (disabilities questionnaire for people aged 6 and more years and a questionnaire on limitations for infants aged 0 to 5 years) and a questionnaire aimed at the main carers.

1st Phase

Household questionnaire

The person is interviewed (person of reference in the dwelling, their spouse or partner or another person) who is present at that time in the dwelling and is informed, and who is asked a series of questions to find out what disabilities each of the people resident in the dwelling might have, expressed in comprehensible terms by people of any cultural level. The aim is to detect and identify all people in the household that are interviewed and have some disability.

They are also asked for information about the type of composition of the household, and for information about parental relations (with the person of reference in the household and with people that have some disability), country of birth, nationality, marital status and who they live with, level of studies obtained, disability certificate (≥33%), relation with economic activity, professional situation, occupation of the company and province of residence.

It ends with a section in relation to the conditions and accessibility of the dwelling and private expenses generated on the household as a result of the disability.

2nd Phase

A) Disabilities questionnaire (people aged 6 and more years).

This second phase seeks to interview people aged 6 and more years that are the object of study, i.e. that have been identified in the previous stage as people that have some kind of disability. Interviews are conducted by means of the disabilities questionnaire. This has to be answered as much as possible by the person who is the subject of the interview. The questionnaire starts by verifying the disabilities indicated by the informant for the household questionnaire. It then asks about the characteristics of the disabilities: degree of severity of each, start age, impairment of origin and whether receiving supervision or personal care or getting outside help.

For each disability only one deficiency is considered. This is for no other reason than the way that one disability can lead to more than one impairment or it can be difficult to find the true origin of the disability, in which case the following guidelines have to be observed:

• When the disability was produced by an illness than has been overcome or that did not evolve by leaving a mark, the impairment will here be the organ, system or apparatus in which that has been affected.
• When the disability is the consequence of a degenerative or progressive illness that has not been overcome, the impairment will be the affected apparatus or system, regardless of whether the adverse affects have affected another organ.
• A disability can be produced by a long-term but curable illness, at the same time that the illness is directly affecting the organ, apparatus or system and the effects of this illness can be seen. In general this will affect the same organ that the illness has affected, and therefore the two paths lead to the same impairment.
• If the disabilities are related with impairments that affect various organs or systems of the body this is the result of disorders classified here as multiple impairments.

B) Limitations questionnaire (minors aged 0 to 5 years)

Questionnaire aimed at the population aged under 6 years and that at present has some limitation, and in these cases must be answered by the child's parents or guardians. No detailed study is made of the disabilities in this group, given the difficulties with detection. However, it does research 18 possible limitations that can be detected among infants at this age.

In this investigation the total number of minor infants aged up to 6 years is presented by sex and rate per thousand in Catalonia for this population group.

C) Questionnaires for main carers

With respect to the characteristics of carers, a specific questionnaire has been introduced that must be answered, as far as possible, by the main carer. The objective is to find out information about the demographic and social characteristics of carers, the level of professionalization, the time they dedicate to their work and the types of carer, their own state of health and professional aspects, among others.

4.4. 4. Basic characteristics forming the object of study

4.4.1. Disabilities (people aged 6 and more years)

In the context of the EDAD, it is considered that a person has a disability even if they can overcome it with external technical aids or with the help of another person. The disabilities are divided into 8 groups, and 44 types of disability, which are listed hereafter:

1. Vision
   • 1.1. Perceiving any image
   • 1.2. Detail visual tasks
   • 1.3. Overall visual tasks
   • 1.4. Other vision problems
2. Hearing
   • 2.1. Receiving any sound
   • 2.2. Hearing loud sounds
   • 2.3. Hearing speech
3. Communication
   • 3.1. Producing spoken messages
   • 3.2. Receiving spoken messages
   • 3.3. Communication of written messages
   • 3.4. Communication of messages through gestures, signs or symbols
   • 3.5. Holding a conversation (only cognitive or intellectual problems)
   • 3.6. Communication through devices and communication techniques
4. Learning and application of knowledge and development of tasks (only problems of a cognitive or intellectual nature)
   • 4.1. Intentional use of the senses (watching, listening, etc.)
   • 4.2. Basic learning (reading, writing, counting, etc.)
   • 4.3. Undertaking simple tasks
   • 4.4. Undertaking complex tasks
5. Mobility
   • 5.1. Changing basic body postures
   • 5.2. Maintaining the position of the body
   • 5.3. Getting around inside the home
   • 5.4. Getting around outside the home
   • 5.5. Getting around via passenger transport
   • 5.6. Driving vehicles
   • 5.7. Picking up and carrying objects
   • 5.8. Moving objects with the upper limbs
   • 5.9. Fine hand use
6. Self-care
   • 6.1. Washing oneself
   • 6.2. Caring for body parts
   • 6.3. Toileting related to urination
   • 6.4. Toileting related to defecation
   • 6.5. Toileting related to menstruation
   • 6.6. Dressing and undressing
   • 6.7. Eating and drinking
   • 6.8. Looking after one's health: following medical prescriptions
   • 6.9. Looking after one's health: avoiding dangerous situations
7. Home life
   • 7.1. Acquisition of goods and services
   • 7.2. Preparation of meals
   • 7.3. Doing housework
8. Interpersonal interactions and relationships
   • 8.1. Basic interpersonal interactions
   • 8.2. Relating with strangers
   • 8.3. Formal relationships
   • 8.4. Informal social relationships
   • 8.5. Family relationships
   • 8.6. Intimate relationships

4.4.2. Limitations

A limitation is any area of serious or important difficulty that affects infants under 6 years and has its origin in an impairment. This publication does not present results on limitations as mentioned earlier.

4.4.3. Impairments

An impairment is considered the loss or anomaly to an organ or a function of an organ, that has led to one or more disabilities.

1. Mental impairments
   • 1.1. Developmental delay
   • 1.2. Profound and severe intellectual impairment
   • 1.3. Moderate intellectual impairment
   • 1.4. Mild intellectual impairment
   • 1.5. Borderline intelligence
   • 1.6. Dementia
   • 1.7. Mental illness
   • 1.8. Other mental and behavioural disorders
2. Visuals impairments
   • 2.1. Total blindness
   • 2.2. Poor eyesight
3. Hearing impairments
   • 3.1. Prelocution deafness
   • 3.2. Postlocution deafness
   • 3.3. Hard of hearing
   • 3.4. Balance disorders
4. Language, speech and voice impairments
   • 4.1. Muteness (not through deafness)
   • 4.2. Difficult or incomprehensible speech
5. Osteoarticular impairments
   • 5.1. Head
   • 5.2. Spinal column
   • 5.3. Upper limbs
   • 5.4. Lower limbs
6. Nervous system impairments
   • 6.1. Paralysis of an upper limb
   • 6.2. Paralysis of a lower limb
   • 6.3. Paraplegia
   • 6.4. Tetraplegia
   • 6.5. Motor control and/or muscular tone disorders
   • 6.6. Other impairments of the nervous system
7. Visceral impairments
   • 7.1. Respiratory system
   • 7.2. Cardiovascular system
   • 7.3. Digestive system
   • 7.4. Genitourinary system
   • 7.5. Endocrine-metabolic system
   • 7.6. Haematopoietic system and immune system
8. Other impairments
   • 8.1 Skin
   • 8.2 Multiple impairments
   • 8.3 Impairments not classified elsewhere

4.4.4. Activities of daily living (ADL)

The disabilities in the activities of daily living in the survey EDAD-2008 are as follows:

1. Washing oneself
2. Caring for body parts
3. Toileting related to urination
4. Toileting related to defecation
5. Toileting related to menstruation
6. Dressing and undressing
7. Eating and drinking
8. Looking after one's health: following medical prescriptions
9. Looking after one's health: avoiding dangerous situations
10. Acquisition of goods and services
11. Preparation of meals
12. Doing housework
13. Changing basic body postures
14. Maintaining the position of the body
15. Getting around inside the home
16. Getting around outside the home
17. Intentional use of the senses (looking and listening)
18. Performing simple tasks

4.4.5. Severity

The increase in life expectancy and the consequent ageing of the population makes it relevant to understand the variations in the years lived and the quality of life and the health conditions of the same.

The severity of the disability refers to the degree of difficulty in carrying out each activity with aid (in the case that the person receives aid) or without aid.

• Without any difficulty
• With moderate difficulty
• With severe difficulty
• Cannot carry out the activity

4.4.6. Aid received

The types of aid are considered: technical and personal assistance.

• Technical aid: is considered any product, instrument, equipment or technical system that a disabled person can use or that was designed for that person, specifically produced for that person or any other to compensate, alleviate or neutralise the disability (hearing aid, artificial limbs, wheelchair, etc.).
• Personal assistance: this is considered any direct aid provided to another person with a disability for their everyday tasks.

  The principal aid that personal assistance can refer to is personal care: washing, bathing, eating and drinking, help with household tasks: cooking, ironing, assistance with travelling, supervising people with mental problems, etc.

5. EDAD centres (EDAD-c)

The fundamental variable of the object of study in EDAD-c is disability. The concept of disability in EDAD-c is identified with the use in EDAD-h: important limitations on everyday activities, that affect or are predicted to have an effect for more than a year and that have their origin in an impairment.

The main objectives of the EDAD-c are to estimate the number of people with a disability that reside in certain collective establishments (old peoples homes, centres for people with a disability aged under 65 years, psychiatric hospitals and geriatric hospitals), and their geographic distribution, to find out the characteristics of people with a disability and in situations of dependence, identify impairments, identify needs and demands for care, and the supports they receive and their characteristics. Objectives include finding out about technical aid, special adaptations (in the centre, workplace...), personal care, etc., find out about the main characteristics of the collective centres where people with a disability reside, and the services they provide and make an analysis of the disability from a gender perspective.

The framework used to produce the EDAD-c was based on the following sources:

• IMSERSO database of old people's centres.
• Directory of centres with people with a disability aged under 65 years. (Standardised project description of disability services in Spain (Project DESDE).
• MSC National Catalogue of Hospitals.
• Central Business Directory (DIRCE) of the INE, considering active companies with main activity 8531, "Activities to provide social services with accommodation", CCAE (1993).

To verify the framework of activity, fieldwork was done by sending a letter to all centres containing a brief questionnaire in order to make a posterior sample design for the definitive survey. The variables requested were: ownership, finance, type of residential care, number residential places, number of residents classified by sex and age, number of workers, existence or not of a computerised register of people.

The basic research units are:

• Social Residential Care Centres

  Centres dedicated to temporary or permanent accommodation, where complete and continuous care is provided, with interprofessional socio-health care, for elderly persons and for persons with physical and intellectual disabilities.

  There are different types of Residential Centre, according to the profile of the persons they cater to (they may target persons in dependency situations and persons who can care for themselves), although their essential, therapeutic functions of complete care and accommodation are common to all of them. The following are considered:

  • Residences for elderly persons in a dependency situation.
  • Residences for elderly persons who can care for themselves.
  • Residences for elderly persons in mixed situations (dependency / self-sufficient).
  • Care centres for persons with physical disabilities.
  • Care centres for persons with intellectual disabilities.
  • Care centres for persons with mental illness.
  • Reference centres: centres that perform a dual function: the direct care of persons with a specific type of problem, and the promotion, research and technical aid to other sector resources.
  • Other
• Geriatric hospitals and/or long-stay and psychiatric hospitals (centres with internment).
  • Geriatric and/or Long-Stay Hospitals. Health centres aimed at the specialised and continuous care of interned patients (with a minimum of one night) who require health care, in general, of low complexity, due to chronic processes or because their degree of functional independence for everyday life is reduced, which they cannot provide in their domicile, and require a period of internment.
  • Mental Health or Psychiatric Hospitals. Centres aimed at providing diagnoses, treatment and monitoring for patients who required internment due to mental illness.
• Surveyable person.
  • Person who has been residing in the centre for at least three months.

5.1. Areas of research

• Population scope

  The area of research is aimed at people residing in old people's centres, centres for people with a disability aged under 65 years, psychiatric hospitals and geriatric hospitals.

• Geographic scope

  The area of the research is aimed at all of the national territory.

• Time scope

  Information collection period over three months from May to June 2008.

5.2. Sample design

The EDAD-c is a survey directed at the population resident in collectives that complement the EDAD-h. To make it simpler, a distinction was drawn between old people's homes, centres for minors and hospitals (geriatric and psychiatric).

The sampling technique used was two-staged stratified sampling. In the first stage the unit was the centres, while in the second it was the people residing in them. The framework or the selection of the sample was made by marking a list, formed by the relation between centres appearing in the existing directory at the time that the survey was conducted. For each autonomous community an independent sample was designed.

The size of the state sample was 6,106 residential centres and 11,000 people approximately; in Catalonia, 173 centres and 2,050 people. The centres are selected within each stratum with proportional probability to their size. The people, at each centre, with the same probability. The procedure for selection of the person is random.

Estimators are used for reasons of the application of calibrating methods, in accordance with the auxiliary information available and with the characteristics to be estimated.

5.3. Phases of the survey

The information is collected between May and June 2008.

The statistics are dealt with in (EDAD-c) two phases, with the corresponding questionnaires: questionnaire on centre or hospital and questionnaire on person (6 years and more).

In the 1st phase, information is collected by means of the centre questionnaire, which is self-filled with the characteristics of the centre or hospital, and provided by the person that the centre's management designates with that duty. This questionnaire is completed with the random selection of the people that must answer the individually based questionnaire. This questionnaire is aimed at people selected beforehand to determine whether they have or haven't any disability, and the method for collecting information for the personal questionnaire must be a personal interview, which shall be provided by the same person, as long as this is possible, and if not, it must be provided by a sufficiently informed other person (from the centre or family).

First phase: Questionnaire on the centre or hospital questionnaire

In the first phase information is requested, through the self-fill questionnaire, on different characteristics of the centre or hospital.

Centres:

• General data on the centre or hospital: Type of centre, specialisation, ownership, finance and management.
• Provision of places and rooms.
• Distribution of groups by age and sex of people resident in the centre.
• Services offered by the centre.
• Facilities available in the centre.
• Evaluation protocols (care for the control of types of diet, use of subjections, diapers...)
• Staff at centre: staff by professional category and percentage of time the health and psychosocial staff spend on personal care.
• Centre's expenses.

This questionnaire ends with a random selection of people that must answer in person.

Hospitals:

• General details of the hospital: aim of the hospital (geriatric or psychiatric), ownership, finance and management.
• Provision of beds.
• Distribution of groups by age and sex of people resident in the centre.
• Staff at centre: staff by professional category and percentage of time the health and psychosocial staff spend on personal care.
• Centre's expenses.

This questionnaire ends with a random selection of people that must answer in person.

Second phase: Personal questionnaire

The aim is to determine whether the people selected in the previous stage have or do not have any disability by holding a personal interview to discern what these are. After a list of questions of a general nature on the person, it asks if they have any of the 44 disabilities being researched, and about the degree of severity, start age, impairment caused by each and whether any supervision or personal care is provided or any external techniques. As well as discrimination as a result of the disability, networks and social contacts, personal autonomy and accessibility.

6. Differences between the editions of 1999 and 2008 (EDDES99 and EDAD2008)

The differences between the editions of 1999 and 2008 (EDDES99 and EDAD2008) are as follows:

• Differences in the formulation of disabilities: EDDES-99 detected persons with some disability by asking directly "if they had some kind of disability". However, EDAD08 asks about limitations of activity, as is proposed by the ICF, to measure the negative aspects of the "activities and participation" component.

  The groups of disabilities considered practically coincide with those recognised in the EDDES-99, although the latter will use, as much possible, the ICF terminology to name them. However the coincidence is not exact, some disabilities in EDDES-99 have been split according to ICF criteria, and new ones have been included on considering them of interest. The number of disabilities has risen in the EDAD08 from 36 to 44.

  Remaining are those relating to vision and hearing, as in the EDDES-99, though this does not always strictly follow the ICF, as in these cases the question is impairment and not disability.

• Differences between limitations: It was agreed to continue with the scheme of the EDDES-99, though it also decided to improve the wording of some of the questions, clarifying them according to the objectives, adding a reference age and splitting up questions to complete the previous list of limitations.
• Differences between impairments: correspond to illnesses, and therefore, do not appear in the ICF as a function or as a structure. Bearing in mind that the fundamental target study variable in this survey is disability and that the different users need impairment data based on the previous classification, it was decided not to demand the application of the ICF, and therefore provide continuity to the series initiated with EDDES-99.
• The gender perspective: The EDAD-08 incorporates the gender perspective by introducing in the survey a group of variables that allow for adequately reflecting the situations of equality or inequality due to gender. Some examples of such variables are: relationship with economic activity, education, discrimination for disability, social networks and contacts, social and health services, carers. This latter case tells us about the role of women as informal carers and the consequences on their family, working, free time and leisure lives.