The relationship between official Catalan statistics and citizens is established in the European Statistics Code of Practice which Idescat has adopted as a model to aspire to. Following those principles and in accordance with the rights of citizens, statistics must be relevant to citizens, they must satisfy the users' needs, they must be accessible and as clear as possible, and they must represent as small a burden on those surveyed as possible. As for their duties, it is obligatory for citizens, and more generally households, businesses and administrations, to supply the information necessary to prepare the statistics of interest to the Government of Catalonia, with the statistical authorities committing to guaranteeing their confidentiality.
Cooperation by the population and companies in responding to the questionnaires used to gather official statistics is legally obligatory, with the purpose of ensuring an appropriate response rate and consequently reliable statistical results (chapter I of the Statistical Law of Catalonia).
The Catalan Parliament grants all statistics included in the Statistical Plan for Catalonia, and the Annual Programmes for Statistical Action that are derived from it, official status or the status of public interest. As the official statistical body of the Government of Catalonia, the Catalan Parliament charges Idescat with the task of drawing up a large part of this information, as well as planning, programming and coordinating the statistical production of other entities that participate in the Statistical System of Catalonia, as established in the Statistical Law of Catalonia and the Law on the Statistical Plan for Catalonia (chapter II of the Statistical Law of Catalonia).
The Statistical Law of Catalonia protects the information provided by survey respondents for the purposes of official statistical activities, regardless of whether this information comes from people, companies or institutions. Specifically, the statistical secret (chapter IV of the Statistical Law of Catalonia) protects individualised data gathered on questionnaires, which can neither be made public nor be shared with any other person or entity, not even with public administrations except for those that are also bound by the obligation of the statistical secret.
Likewise, all the staff at Idescat and other bodies that participate in official statistics in Catalonia make a solemn oath to preserve the statistical secret and could face severe penalties should they violate this oath.
Additionally, the obligation to preserve the statistical secret extends to the publication of results, such that both Idescat and the remaining bodies within the Statistical System of Catalonia take special care to prevent individual data to be deduced from the information published.
In terms of confidentiality when processing the individual data subject to the statistical secret, a network of physical, logical and procedural security systems, adopted by Idescat's Security Document, protects the individualised information from unauthorised access. In the case of Idescat, all confidential information is exclusively stored in and processed through its internal networks with no connections to the outside, in order to ensure access security.
Often, citizens wonder why they have been selected to answer a survey when other people in their neighbourhood or city, friends or family members have not been asked. This is because most official statistics are done using samples, meaning people are randomly chosen to take part, in a way that is representative of the total population being studied. In this sense, people are usually chosen according to sex, age, place of residence or similar data.
To choose the people to be included in a sample, the bodies that generate official statistics in Catalonia may use the Population Register of Catalonia, which is an administrative register containing the updated data that is obligatorily registered by residents in the municipal censuses of inhabitants of all the town halls in Catalonia, and which is looked after by Idescat and regulated by the Statistical Law of Catalonia.
In the case of telephone surveys, the telephone numbers are obtained from the same telephone directories used by the public.
The majority of surveys aimed at companies are sample-based. This means that only certain companies are chosen within each territorial or sectorial domain. As a whole, the companies that form part of the sample represent the sector as a whole or the economic activity being analysed. Normally, the companies that participate in the sample are randomly chosen from a directory so that they maximally represent other companies with similar characteristics in terms of, say, the type of activity or number of employees. Some companies must always be included in the sample because the contribute substantially to the activity branch or the territory they are part of; it would not be possible to obtain reliable data without information on them. A small number of company surveys are conducted like censuses, that is, they include all the companies of a certain size or performing significant activity that belong to the same domain. In contrast, a census of all the companies is used when the realm of analysis includes few companies or companies that differ greatly from each other. In these cases, a sample would not accurately reflect the entire domain being studied.
Idescat and the other bodies within the Statistical System of Catalonia attempt to achieve a balance between the informant's burden of responding to the different surveys and the need to obtain detailed data from the population and companies. To this end, Idescat has reached collaboration agreements with the National Statistical Institute (INE) in order to make joint actions with the purpose of avoiding reduplicating statistical operations and thus significantly reducing the number of questionnaires aimed at the population or companies. This is the case of such important statistics as the Survey of Industrial Companies and the Agricultural Census, as well as statistics on the labour market and on the structure of the population.
Whenever possible, the bodies producing official statistics take advantage of data already supplied by the population and companies to the public administration for legal-administrative purposes. This is the case, for example, with a large group of health statistics, much of the statistics generated on education or the statistics on the vehicle fleet. To this end, approximately 60% of the statistics that make up the annual Action Programme originate from administrative sources.
However, these administrative registers do not contain all of the information required by the Government of Catalonia, financial and social organisms or other users of statistics, meaning that it is often necessary to carry out specific additional surveys.
The dissemination of statistical results is a decentralised task; that is, each body in charge of designing and generating official statistics also tends to be the body that disseminates the results. Despite this, Idescat's webpage is an ideal vehicle for finding out about the results of Catalan official statistics in that it offers very extensive information on both the statistics generated by the Institute itself and on other statistics conducted by the different bodies participating in the Statistical Plan of Catalonia.
The activities included in the annual statistical action programmes that involve obligatory cooperation by the population and companies, through official surveys in which Idescat participates, can be examined in the current Annual Programme of Statistical Actions.