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1. Objectives

The Survey on disabilities, impairments and state of health of 1999 has the following objectives:

  • To estimate the number of people living in family dwellings who are suffering from some type of handicap, and to find out what their handicaps are.
  • To find out the seriousness of the different types of disabilities which have given rise to these handicaps, and to identify the disabilities associated with each of the social groups.
  • To find out the causes behind these disabilities in order to gather data to develop social policies aimed at reducing those disabilities that can be prevented.
  • To estimate the number of people who are at a disadvantage in terms of their environment as a result of their disability, and to analyse these disadvantages.
  • To find out the structure of the population living in family dwellings who suffer from some type of disability and to seek profiles of the population's state of need as well as how to provide information on the risk factors associated with these phenomena and on the problems of families with a disabled member.

Other objectives of these statistics are to provide information on the socio-health differences between people with and without disabilities and to identify risk factors that affect the population's overall state of health by means of researching certain living habits as well as the use of health services.

2. Basic concepts

On the basis of the International classification of functioning, disability and health (ICF) a list of disabilities and deficiencies was prepared to reflect the caustics of these phenomena in Spain, maintaining as much comparability as possible with the previous survey, and also with the international sphere.

The ICF establishes three levels of consequences of the problem. On the first level, there are symptoms, signals or manifestations of a disorder in relation to an organ or a function of the same, whatever the cause. This manifestation of a disorder is called a deficiency. A deficiency is any loss or anomaly to an organ or the inherent function of that organ.

On a second level are disabilities, which are the consequences that the disorder produces towards the capacities or autonomy of the person.

Finally, the third level corresponds to handicaps, which are the consequences that the disorder produces on a social scale and the disadvantages caused to the person in relation to other people around them.

The application of this classification involves a series of practical problems. The following is a list of the problems detected, and the decisions made to overcome them:

  • It was decided that the existence of a disability should be the starting point for the survey. This option was adopted in consideration that the Classification of deficiencies uses highly medical terminology that is considerably complex for people alien to the field of health and that the ICF includes a large number of deficiencies that do not lead to disabilities. The use of deficiencies would have swung the operation towards a more medical than social angle.
  • The disabilities and impairments studied adapt to a language that is understandable to both interviewers and interviewees.
  • If the disability is an important difficulty that makes it impossible or seriously difficult for a person to carry out normal activity, the first thing that had to be done was delimit the primary elementary activities, in order to be able to ask the surveyed persons which of those activities they were incapable of doing. As the number of possible activities that a person might carry out is interminable, we had to restrict them to fundamental activities.
  • Disabilities may not appear alone, but rather, an individual may have two or more disabilities, which may be independent of each other, or may have originated from the same impairment. This makes it necessary to make a decision as to which disabilities should be studied.
  • Another issue to consider was to determine from what moment a disability is the target of study, as some apparently important disabilities do not significantly limit the activity of a person, and so it was necessary to establish clearly in which cases it could be considered a disability.
  • Very closely related to the previous section is how to determine when a disability should be a target of study depending on its short or long-term permanence, given that passing limitations can be overcome.
  • Many limitations may cease to be limitations with the help of some kind of instrument or device, so a criterion was established for these.
  • Another important point was the problem of age. It is very difficult to know whether the disability of a child will be of a long-term nature or transitory, and another problem could emerge that produces this limitation in the future and that is not presently detectable. This can also occur with elderly people, in the case of some disabilities, such as for example the inability of an 80-year old to drive a car, which is debatable. These considerations led to the need to establish different age groups when presenting the results.

The solutions for these difficulties were as follows:

  • Disability is understood to be, for the purposes of this study, any total serious limitation with a long-lasting affect on a person's everyday activities, and which is caused by an impairment.
  • For all people surveyed, we collected all of the disabilities they have, whether they are independent of each other or not.
  • The idea is to quantify the disabilities that people perceive. Therefore the survey collects all disabilities that the person believes to seriously limit their activity.
  • A limitation may be considered long-term when the nature of the same carries this feature implicitly, or when the time that it has lasted or that it is expected to last is equal to or longer than one year.
  • The survey studies all disabilities that persons have, even if they are managed with the use of some kind of technical aid. It is important to point out that the study also considers disabilities to be those that have been overcome through the use of external technical aid.
  • In order to deal with the problem of children and the elderly, three age groups are considered. A first group, for children 0 to 5 years of age, and a second for people aged 6 to 64 years and a third for people aged 65 and above. In the case of the elderly group, the same variables are studied as for the group aged 6 to 64, but the results are presented separately.

The following are the definitions of the basic characteristics that are the targets of study for this survey.

A perceived disability, for the purposes of this study, is considered to be any serious limitation that has a long-lasting effect on the activity of the sufferer and that has originated from a deficiency. It also contains some disabilities that do not originate from a deficiency, but that stem from degenerative processes in which the age of the person has a decisive influence. An activity is seriously limited when the subject him or herself so considers it to be; in other words, the aim is to quantify the disabilities that are perceived by this survey's study population.

People can perform numerous activities in their everyday life, but for the purposes of the survey, we have only collected information on a limited number of basic and common activities. Of these 36 everyday activities selected, we asked about the level of difficulty for carrying them out. In order to categorise how a person with a disability can carry out everyday activities, it was considered that they should at least have one of the following disabilities:

  • Changing the position of the body
  • Getting up
  • Going to bed
  • Getting around inside the home
  • Getting around without a means of transportation
  • Washing oneself and controlling bodily functions
  • Dressing oneself
  • Eating and drinking
  • Shopping, preparing meals, washing and ironing clothes
  • Cleaning and maintaining the home
  • Looking after the welfare of other family members

3. Phases of the survey

Before conducting the definitive survey, in 1998 we undertook a pilot survey, in order to detect and evaluate the possible incidents that could arise during the fieldwork. Specifically, we evaluated the difficulties that households had responding to the survey, as well as those encountered by the agents conducting it. The pilot test was conducted by 8 interviewers using a sample of 500 family homes.

For the definitive questionnaire and planning derived from this fieldwork, this statistical operation was divided into three phases. In each of these phases, households were asked to answer one of the parts into which the complete questionnaire was divided.

First phase: Household questionnaire

The first phase related to interviewing all of the members of a household or residents in the same that suffered some kind of disability or limitation. They were therefore asked a series of questions to determine all of the disabilities that each person suffered. They were also asked for information on all members of the household in relation to age, sex, nationality, marital status, relation with the main person in the household and other basic issues such as the level of education, relation with economic activity, professional situation, occupation, establishment activity, health cover, possession of disability certificate or internment in a collective establishment during the last 12 months. They were also asked for information on the type of household and the composition of the same, the amount of regular income received by the household and any social or extraordinary benefits received.

Second phase

This was divided into two different questionnaires depending on whether the person was 6 years or more, or a child aged up to 6 years.

A. Questionnaire on the disabilities and deficiencies of people aged 6 years or more

The aim was to interview people aged 6 years or more that are the targets of the study, i.e. that suffer from some disability. A questionnaire was given on disabilities and deficiencies to any people aged 6 years or more in the household that had stated in the previous questionnaire that they suffered from a disability. They were asked to report on the level of severity of each disability, the developmental forecast, the age when it started and any additional information on technical aids or personal care whether received or applied for, as well as any deficiency that had originated from any of these disabilities.

Once the disabilities that had been caused to each of the people as a result of their deficiency had been determined, we asked about the problem that caused this deficiency, its duration, and the age it started. They were also asked questions in relation to personal care, whether they belonged to non governmental organisations or charities, and also about changes of residence as a result of suffering from the disability. A part of the questionnaire deals with the amount of use of health and social services: types of services, the frequency of use and requests satisfied and not satisfied. They were also asked whether they receive or have received any type of financial or physical aid.

In order to analyse social integration, they were asked for information on their relation with economic activity before and after the onset of the disability, any measures for promoting their employment and the problems faced by inactive or unemployed people, as well as their level of finished studies, studies being taken and integration at school.

B. Questionnaire on the disabilities and deficiencies of people aged 0 to 5 years

Questionnaire aimed at the population aged less than 6 years and that currently suffer from some kind of limitation that is the target of study of the survey. This publication does not present the results for this population, due to the small number of people that were interviewed, which has meant that the estimation of results is not statistically significant enough.

Third phase: Health questionnaire

Information is collected on a single member of each of the households interviewed, who is selected randomly from all members. This phase of the survey has not been exploited in relation to this presentation of the results.

4. Scopes of investigation

  • Population scope

    The survey is conducted on all people that live in main family homes. If there are two or more households in the home, the survey is conducted for all the households living in it.

  • Geographical scope

    The survey is conducted throughout the Spanish territory.

  • Time scope

    The information is collected during the second quarter of the year 1999.

5. Sample design

Type of sampling

The survey is aimed at the population that resides in main family homes. The sample technique used is that of the stratified two-stage sample.

In the first stage, the census sections are selected. For each province, the sections are grouped into strata, on the one hand, in accordance with the demographic importance of the municipality to which they belong, and on the other, in accordance with the socio-economic category of the households located there.

In forming the strata, we considered two types of municipality. The self-represented are those that a result of their category within the province must always have sections in the sample. Self-represented municipalities are those that are:

  • The capital of the province
  • Municipalities that due to their number of inhabitants and due to proportional affixation within the province corresponded to at least 12 sections of the sample.
  • Municipalities with an outstanding situation within the sample but where there are no other similar ones with which they can be grouped, even though they proportionally correspond to at least 12 sections of the sample.

Co-represented municipalities: these are those that within the province form part of a group of demographically similar municipalities and that are represented commonly. In accordance with this classification, we establish new and different strata that correspond to the previous concepts. Censuses and population registers are the sources used and which provided the necessary information to update the stratification for each province, in accordance with the distribution of the population of the municipalities.

To form the substrata, we considered the socio-economic category of the households located in the sections. This information made it possible to classify the economically active population of the section into four groups:

  • Labourers
  • Self-employed workers
  • Managerial and professional employees and administrative personnel
  • Other workers

There are sixteen substrata, fifteen of which are formed in accordance with the percentage population of groups 1, 2, 3 and 4, and the sixteenth is formed by the sections with a high number of inactive people.

In the second stage, we selected family homes, of equal probability by using random start systematic sampling. In order to fill in the health questionnaire, we randomly selected one member of the household.

Size of the sample

The sample was made up of 79,000 family homes throughout Spain, distributed into 3,000 census sections. For Catalonia, the sample was 7,443 households and 21,713 individuals. The affixation of the sample was performed using mixed affixation. The sections were distributed into provinces by assigning uniform and fixed parts, and the remainder in a proportional way to the size of the province. The distribution between strata was performed proportionally to the size of the stratum, but strata were strengthened if they contained larger sized municipalities, as it was expected that there would be greater variability in the behaviour of the population.

Sample selection

The sections were selected using a probability that was proportional to their size. Homes were selected, in each section, using systematic random start sampling method. To select the person who was to fill in the Health Questionnaire, we used a random system that assigned the same probability to all of the people in the household.

6. Estimators

We estimated the following characteristics:

  • In relation to limitations, disabilities and deficiencies.
  • In relation to the state of health.

In order to estimate both types of characteristic, we used ratio estimators in order to balance the distribution of the sample to the distribution of the population that was known from external sources. For this reason, we made an adjustment in consideration, on the one hand, of the population of the family homes distributed by province and stratum, and on the other, of the population of the family homes distributed by province and age and sex groups. In both cases, the populations were obtained from the demographic population projections.

7. Basic characteristics of the target of study


Disability is any serious limitation that affects or is expected to affect for more than a year the ability of the sufferer and that originates from a deficiency. A person is considered to have a disability even when they have managed to overcome it thought the use of external technical aid.

The disabilities of people aged 6 years or more are as follows:

  • 1. Seeing: people with serious or important seeing difficulties, whether short-sighted or long-sighted. Unlike other disabilities, this group only contains very important difficulties that have not been overcome though the use of glasses or contact lenses, whatever the cause might be.
    • 1.1. Disability in receiving any image
    • 1.2. Disability in overall visual tasks
    • 1.3. Disability in detailed visual tasks
    • 1.4. Other visual disabilities
  • 2. Hearing
    • 2.1. Disability in receiving any sound
    • 2.2. Disability in hearing loud sounds
    • 2.3. Disability in hearing speech
  • 3. Communicating
    • 3.1. Communicating through speech
    • 3.2. Communicating through alternative languages
    • 3.3. Communicating through non-signing gestures
    • 3.4. Communicating through conventional reading and writing
  • 4. Learning, applying knowledge and performing tasks
    • 4.1. Recognizing people, objects and orienting oneself in space and time
    • 4.2. Remembering information and recent and/or past events
    • 4.3. Understanding and carrying out simple commands and/or performing simple tasks
    • 4.4. Understanding and carrying out complex commands and/or performing complex tasks
  • 5. Getting around
    • 5.1. Changing and maintaining different body positions
    • 5.2. Getting up, lying down, standing or sitting
    • 5.3. Getting around inside the home
  • 6. Using arms and hands
    • 6.1. Moving-carrying light objects
    • 6.2. Using utensils and tools
    • 6.3. Manipulating small objects with hands and fingers
  • 7. Getting around outside the home
    • 7.1. Getting around without a means of transportation
    • 7.2. Getting around using public transport
    • 7.3. Driving one's own vehicle
  • 8. Caring for oneself
    • 8.1. Caring for personal hygiene without assistance: washing oneself and taking care of one's appearance
    • 8.2. Controlling bodily functions and using the toilet without assistance
    • 8.3. Dressing, undressing, grooming
    • 8.4. Eating and drinking
  • 9. Performing housework
    • 9.1. Shopping and supervising supplies and services
    • 9.2. Preparing meals
    • 9.3. Washing and ironing clothes
    • 9.4. Cleaning and maintaining the house
    • 9.5. Looking after the welfare of other family members
  • 10. Relations with other people
    • 10.1. Maintaining affectionate relationships with close family members
    • 10.2. Making and keeping friends
    • 10.3. Dealing with co-workers, superiors and subordinates


A limitation is considered to be any serious or important difficulty that affects children under 6 years and that originates from a deficiency. In the case of limitations, we are not presenting results here, has stated earlier.


A deficiency is considered to be any loss or anomaly of an organ, or the functions of that organ, that has led to one or several disabilities.

  • 1. Mental impairment
    • 1.1. Developmental delay
    • 1.2. Severe mental retardation (intelligence quota between 0-34)
    • 1.3. Moderate mental retardation (CI between 35-49)
    • 1.4. Mild mental retardation (CI between 50-80)
    • 1.5. Dementia
    • 1.6. Other mental disorders
  • 2. Visual impairment
    • 2.1. Total blindness
    • 2.2. Poor eyesight
  • 3. Ear and hearing impairment
    • 3.1. Pre-speech deafness
    • 3.2. Post-speech deafness
    • 3.3. Hard of hearing
    • 3.4. Balance disorders
  • 4. Language, speech and voice impairment
    • 4.1. Muteness (not due to deafness)
    • 4.2. Incomprehensible or difficult speech
  • 5. Osteoarticular impairment
    • 5.1. Head
    • 5.2. Spinal column
    • 5.3. Upper limbs
    • 5.4. Lower limbs
  • 6. Nervous system impairment
    • 6.1. Paralysis of an upper limb
    • 6.2. Paralysis of a lower limb
    • 6.3. Paraplegia
    • 6.4. Tetraplegia
    • 6.5. Motor coordination disorders
    • 6.6. Other disorders of the nervous system
  • 7. Impairment from visceral disorders
    • 7.1. Respiratory system
    • 7.2. Cardiovascular system
    • 7.3. Digestive system
    • 7.4. Genitourinary system
    • 7.5. Endocrine/metabolic system
    • 7.6. Immune and blood-producing system
  • 8. Other types of impairment
    • 8.1. Skin
    • 8.2. Multiple impairments
    • 8.3. Impairments not classified elsewhere

Severity of the disability

The severity of the disability refers to the degree of difficulty the person has for doing a certain activity. This can be:

  • 1. Moderate: If the person does the activity with no difficulty, because they receive help or because they can do the activity with only moderate difficulty.
  • 2. Severe: A person is considered to have a severe difficulty if they can only do the activity with major difficulty.
  • 3. Total: It is considered to be total severity if the person has total difficulty and cannot do the activity.

Aid received

Two types of aid are considered: technical and personal.

  • 1. Technical aid: These are technical products, instruments, equipment or systems addressed at people with disabilities, that were specifically produced for them or that are available to anybody, in such a way that they prevent, compensate for, alleviate or neutralise the disability.
  • 2. Personal aid: This is direct aid offered by another person in order for the disabled person to cope with their everyday activities.

8. Information collection

Information was gathered in the months of April to July of 1999. It was done by means of provincial delegations of the INE by means of a personal visit to an effective sample of 70,402 households, in which data was gathered by means of personal interviews dealing with all the people living in the same. The total number of people interviewed was 217,760, of whom 207,292 were 6 years of age or older, and 10,468 under 6. In Catalonia, the sample was of 7,443 households and 21,713 individuals.

9. Recording of the information

The questionnaires were recorded by the ONCE Foundation during the period between July and November of 1999.