Term Definition
Cause and effect diagram
A fishbone-structured diagram for a process, used as a brainstorming tool to help understand or improve the process. The main bone represents the process (e.g., interviewer training), and bones coming off of the main bone are pre-identified factors (e.g., training materials) that may affect the quality of the process. From there potential causes (lack of resources and time) and effects (poor quality materials) can be discussed, and solutions identified. Also known as a fishbone or Ishikawa diagram.

Objective assessment of performance. Based on pre-established criteria, the interviewer either meets the requirements and may proceed to conduct the study interview or does not meet the requirements and may either be permitted to try again or be dismissed from the study. Certification outcome should be documented and filed at the data collection agency.

Closed-ended question

A survey question format that provides a limited set of predefined answer categories from which respondents must choose. Example: Do you smoke?

Yes ___

No ___


A grouping of units on the sampling frame that is similar on one or more variables, typically geographic. For example, an interviewer for an in person study will typically only visit only households in a certain geographic area. The geographic area is the cluster.

Cluster sampling
A sampling procedure where units of the sampling frame that are similar on one or more variables (typically geographic) are organized into larger groups (i.e. clusters), and a sample of groups is selected. The selected groups contain the units to be included in the sample. The sample may include all units in the selected clusters or a sub-sample of units in each selected cluster. The ultimate purpose of this procedure is to reduce interviewer travel costs for in person studies by producing distinct groups of elements where the elements within each group area are geographically close to one another.
Code structure

List of descriptions of variable categories and associated code numbers. Also referred to as code frame, coding frame, or codes.

A document that provides question-level metadata that is matched to variables in a dataset. Metadata include the elements of a data dictionary, as well as basic study documentation, question text, universe statements (the characteristics of respondents who were asked the question), the number of respondents who answered the question, and response frequencies or statistics.

Translating nonnumeric data into numeric fields.

Coefficients of variation

a measure of dispersion of a probability distribution or frequency distribution, that describes the amount of variability relative to the mean.

Cognitive interview
A pretesting method designed to uncover problems in survey items by having respondents think out loud while answering a question or retrospectively.
Cohen’s kappa

A statistical measure that accounts for degree of chance of agreements between coders.


The extent to which differences between survey statistics from different countries, regions, cultures, domains, time periods, etc., can be attributable to differences in population true values (Johnson & Mohler, 2010). In other words, whether the concepts are comparable or not. It is often referred as “equivalence, functional equivalence, similarity, or some other frame of reference” (Johnson & Mohler, 2010). Improving comparability implies that error due to translation has to be minimized. In terms of questionnaire translation for multi-national, multi-cultural and multi-regional surveys the aim is to achieve the defined statistical level of comparability across all local versions (expressed in minimized translation error).

A person who carries out comparative studies, especially a student of comparative literature or comparative linguistics.
Complex survey data (or designs)

Survey datasets (or designs) based on stratified single or multistage samples with survey weights designed to compensate for unequal probabilities of selection or nonresponse.

Computer assisted recorded interviewing (CARI)

A system for audio recording of interviews (or interview parts) that allow for monitoring interviewer performance in the filed/call center and detection of data fraud.

Computer assisted telephone interviewing (CATI)

A telephone interviewing mode in which a computer displays the questions on a screen, the interviewer reads them to the respondent over the phone, and enters the respondent’s answers directly into the computer.

Computer- assisted self interviewing (CASI)
A mode in which a computer displays the questions on a screen to the respondent and the respondent then enters his/her answers into the computer.
Computer-Assisted Personal Interviews (CAPI)

A face-to-face interviewing mode in which a computer displays the questions onscreen, the interviewer reads them to the respondent, and enters the respondent’s answers directly into the computer.

Concurrent mixed mode

A mixed mode design in which one group of respondents uses one mode and another group of respondents uses another.

Securing the identity of, as well as any information provided by, the respondent, in order to ensure to that public identification of an individual participating in the study and/or his individual responses does not occur.
Consent (informed consent)

A process by which a sample member voluntarily confirms his or her willingness to participate in a study, after having been informed of all aspects of the study that are relevant to the decision to participate. Informed consent can be obtained with a written consent form or orally (or implied if the respondent returns a mail survey), depending on the study protocol. In some cases, consent must be given by someone other than the respondent (e.g., an adult when interviewing children).

Consistency is achieved when the same term or phrase is used throughout a translation to refer to an object or an entity referred to with one term or phrase in the source text. In many cases, consistency is most important with regard to technical terminology or to standard repeated components of a questionnaire. Reference to "showcard" in a source questionnaire should be consistently translated, for example. The translation of instructions which are repeated in the source text should also be repeated (and not varied) in the target text.
Construct validity

The degree to which a survey question adequately measures an intended hypothetical construct. This may be assessed by checking the correlation between observations from that question with observations from other questions expected on theoretical grounds to be related.

Constructed variable
A recoded variable, one created by data producers or archives based on the data originally collected. Examples are age grouped into cohorts, income grouped into 7 categories, Goldthorpe-Index, or the creation of a variable called POVERTY from information collected on the income of respondents.
Contact attempt record

A written record of the time and outcome of each contact attempt to a sample unit.

Contact rate
The proportion of all elements in which some responsible member of the housing unit was reached by the survey.
Content management
The software and procedures used to capture, save, organize, and distribute information in digitalized form.
Context effects
The effect of question context, such as the order or layout of questions, on survey responses.
A legally binding exchange of promises or an agreement creating and defining the obligations between two of more parties (for example, a survey organization and the coordinating center) written and enforceable by law.
Convenience sample
A sample of elements that are selected because it is convenient to use them, not because they are representative of the target population.
Conversational interviewing
Interviewing style in which interviewers read questions as they are worded but are allowed to use their own words to clarify the meaning of the questions.
Conversion process

Data processing procedures used to create harmonized variables from original input variables.

Cooperation rate

The proportion of all elements interviewed of all eligible units ever contacted.

Coordinating center
A research center that facilitates and organizes cross-cultural or multi-site research activities.
The person who reviews a text and marks up any changes required to correct style, punctuation, spelling, and grammar errors. In many instances, the copyeditor may also make the corrections needed.

The proportion of the target population that is accounted for on the sampling frame.

Coverage bias
The systematic difference between the expected value (over all conceptual trials) of a statistic and the target population value because some elements in the target population do not appear on the sampling frame.
Coverage error,

Survey error (variance and bias) that is introduced when there is not a one-to-one correspondence between frame and target population units. Some units in the target population are not included on the sampling frame (undercoverage), some units on the sampling frame are not members of the target population (out-of-scope), more than one unit on the sampling frame corresponds to the same target population unit (overcoverage), and one sampling frame unit corresponds to more than one target population unit.

Coverage rate
The number of elements on the sampling frame divided by the estimated number of elements in the target population.
Electronic or printed materials associated with each element that identify information about the element, e.g., the sample address, the unique identification number associated with an element, and the interviewer to whom an element is assigned. The coversheet often also contains an introduction to the study, instructions on how to screen sample members and randomly select the respondent, and space to record the date, time, outcome, and notes for every contact attempt.
A description, usually presented in tabular format, of all the relationships between variables in individual data files and their counterparts in the harmonized file.
Cultural schema

A conceptual structure, shared by members of a cultural group and created from common experiences, by which objects and events can be identified and understood.