June 10, 2021

The following is a brief overview of the specialized terms used in Survey Solutions. The meaning of these terms may be different from what you may have experienced in other systems. Follow the links inside for more detailed explanations in the support site articles.


(aka Two-factor authentication)

Security-enhancing feature requiring authentication of users with two different procedures. In Survey Solutions the two factors are:

  • password, selected by the user, and
  • time-sensitive token (number) generated using an authenticator app (typically installed on the user’s smartphone).


A request/order to conduct one or more interviews as part of a certain survey to a specific user of the Survey Solutions system. Typically contains answers to one or more identifying fields that specify where the data must be collected. (typically 1 document per unit of survey).

Calculated variable

Element of a questionnaire document, which defines a calculated result based on questions and/or other variables using a pre-defined syntax. Variables may be intermediate or final, becoming part of the exported survey data.

Calendar event

An attribute of an assignment and interview, which consists of a message, date, and time components, typically used by interviewers to schedule upcoming visits.

Categories filtering

An efficiency technique that reduces the number of choices in categorical questions by removing the a priori invalid choices based on known information (answers to earlier questions) and a pre-defined syntax expression, which is evaluated for each option of a choice.

For example, a person who is 5 years old may not be related to the household head as father or grandfather, so these categories may be removed from the choices for this question. Yet these categories may be retained for a person who is 60 years old.

Cloud server

A Survey Solutions data server that stores the user data, but is located not in premises of the said user and is accessed not physically, but remotely through communication means. Cf. local server.

Compilation error

An error reported by the Designer while compiling a questionnaire. Questionnaires containing compilation errors may not be imported to a data server and the errors need to be fixed before a survey based on such a questionnaire may start.

Data server

A server that stores the data and hosts the Survey Solutions server component for managing the survey, controlling user accounts, exporting data and other key tasks. Can be set up on a cloud server or a local server.


An online tool (website) to develop electronic questionnaires to be used by the Survey Solutions data servers.

Also, a person who is using this tool to design questionnaires.

Email service provider

An online service providing the capability to send large number of emails. more info


An interview flow control technique in which questions in an interview are shown to the interviewer/respondent ("asked") or not shown ("skipped") depending on the answers to earlier questions, preloaded information, calculated results, etc.


An electronic record of answers and comments to the questionnaire questions delivered in fulfillment of an assignment. (typically 1 or more documents per each assignment of survey).

Interviewing process

The process of filling out an interview by the interviewer (in the CAPI, CATI modes) or respondent (in the CAWI mode).


A particular numeric value, specifying the bounds within which the developers have implemented the functionality of the product. All limits chosen by the developers are listed in the following table.

Limit error

A compilation error caused by overshooting a particular limit.

Linked question

A special kind of categorical question, the categories of which are not defined during the design of the questionnaire, but are defined during the interview when answering certain earlier questions in the questionnaire. Typically replacing the questions “Who…?" or “What is the line number of…?" in the paper-based surveys.

Local server

(aka: Standalone server) A Survey Solutions data server that stores the user data and is located on premises of the same user so that it can be accessed both physically and through communication means. Cf. cloud server.


A downloadable data file containing information about the survey, such as which questions were posed or what options were given, but not individual responses. Cf. paradata, survey data.

Multilingual questionnaire

A questionnaire that contains embedded translations of questions, options and other text into 2 or more languages, and can be switched between them during the interviewing process.


A downloadable data file containing information on the progress of interviews, which includes the actions by the interviewer (such as answering the question) and the responses of the program (such as indication of an error in response to an invalid answer). Cf. metadata, survey data.


Including information known at the start of the survey into assignments to pre-populate interviews with answers to questions already established in earlier waves of the same survey or from other relevant data sources. Typically used in panel surveys, where some attributes, such as date of birth of household members may be preloaded.


An electronic equivalent of a blank questionnaire form containing questions, skips and validation logic, images, lookup tables and other information universally available in all interviews of the survey. (typically 1 document per survey).


In CAPI surveys it is the person answering the questions of the interviewer.

In CAWI surveys is the person completing the web form with answers to the survey questions. Respondents typically know nothing about the working of the Survey Solutions, don’t have any specialized training and treat the interface as a common web page.


A set of permissions, responsibilities and tools that are available to a certain user. For example, HQ users may upload a sample file, or export the survey data, but can’t modify individual answers or complete interviews.

In Survey Solutions the roles are the following:

  • Administrator,
  • Headquarters,
  • Observer,
  • Supervisor,
  • Interviewer,
  • Designer, and Tester.
  • API user.


A special kind of subsection, which repeats its questions multiple times. For example, a demographic section of a typical household survey is a roster repeating questions on name, age, gender and education for every household member. A roster typically appears as a table in paper-based surveys. Some rosters have fixed dimensions (for example, if questions have to be repeated for each of the 7 days of week), while others may change their dimensions depending on the value of the roster trigger.

NB: roaster and rooster are incorrect spellings of roster that sometimes occur in our users' forum discussions.

Roster item

An element of a roster, part of a collection of items, over which the questions are repeated. A roster item typically corresponds to a row in a table in paper-based surveys.

Roster trigger

A question in the questionnaire that determines the size (number of roster items) of the roster.

Sample file

An input to the sample-based survey, which contains identifying information for all the units being surveyed. This file is used by Survey Solutions to automatically create individual assignments for these units.


A group of questions, subsections, static texts or other elements of a questionnaire. Typically equivalent to a chapter or module of a paper-based survey.


A group of questions smaller than a section. May include other subsections. Typically correspond to a smaller topic or a sub-topic of a survey.

Survey data

A downloadable data file containing answers to survey questions in a format accessible by other systems. Cf. metadata, paradata.

Survey unit

Units corresponding to the main level of the interview. Typically these are:

  • households,
  • persons,
  • enterprises,
  • facilities, etc.

But could be more specialized:

  • transactions,
  • events,
  • measurements, etc.


A process of information exchange between two devices, in which they are actualized to make sure each device has necessary information about the activities that occurred on the other device.


Formal notation for expressions and conditions used in Survey Solutions. It is used by the questionnaire designer to specify enabling conditions, validation conditions, filter conditions, and define calculated variables.

Syntax error

A compilation error caused by invalid syntax specification. A questionnaire free of syntax errors is not necessarily correct (may still contain limit errors or implement invalid logic).


All interviewers having a common supervisor. In some reports may include the supervisor himself/herself. (In different arrangements the team may or may not be travelling together, and the supervisor may or may not be joining the interviewers in the travel).

Tester App

An Android-based app implementing the functionality for testing questionnaires during their development and utilized by questionnaire designers and testers. The Tester App is available from the Google Play.

more info.


A registered and authenticated person that is using the Survey Solutions system to perform a certain role in the survey data collection. Users are different from respondents, which usually are not registered.


A process of detecting problems with the responses to questions of an interview. Involves using the responses (answers to questions) as inputs in logically formulated expressions, the result of which determines whether certain responses are acceptable or not. Validation may produce validation errors.

Validation errors

Error messages issued as a result of the validation, indicating that a certain answer or answers are not acceptable based on the logic of the questionnaire developed by its author.


A named logical compartment on the server containing questionnaires, assignments, interviews, and other information. Users may be given permissions to access information in one or multiple workspaces by the administrator. more info