Metadata
Metadata is information about a survey, as distinct from information about a case. Metadata comprises anything that describes the gathered data and can include:
▪Question and category labels and other texts available to interviewers and respondents.
▪Variations of those texts that might be used in different contexts. For example, question texts to be used during interviewing and shorter texts to be used for the associated variables during analysis.
▪Variations of the texts for use in different routing contexts, such as paper-based and Web-based interviewing.
▪Translations of texts.
▪Layout information that describes the way questions are grouped, for example, loops and grids.
▪Presentation information, such as the way questions are laid out on the screen or on the page, and how texts are to be formatted.
▪Rules for deriving new variables from existing variables.
▪Versioning information that contains a complete change history of the metadata.
▪Data source descriptions. For example, the name of the database or file in which the case data is stored.
In addition, the metadata may store routing information that defines the order in which questions should be asked. However, the flexible and dynamic routing information that is used in online surveys is generally controlled by a script and not stored in the metadata.
You use metadata throughout the life of a project. For example, during questionnaire design, you create a set of question texts, question numbers, routing items, and instructions for the interviewer. Before you activate the project, you may want to translate all of this textual information into a number of different languages. At a later stage, you may need to revise the questionnaire, which will create a new version of the metadata.
Depending on the data format being used, the UNICOM Intelligence Data Model can store metadata separately from case data in an extensible markup language (XML) text file with an .mdd (metadata document) file name extension. XML is an industry-standard format similar to HTML that is used to tag text files. It is widely used for storing metadata and in particular, for describing the structure and contents of databases.
Storing the metadata separately from the case data affords considerable improvements in workflow because you can perform operations on the metadata, such as translating and editing, independently of the case data.
See also