Survey CodebooksCodebooks, or data definition dictionaries, are guides to survey data. They contain comprehensive documentation that enables other researchers who might subsequently want to analyse the data to do so without any additional information. A codebook provides information on the structure, contents and layout of a data file. The idea is to define all response options on the questionnaire. For example, question 1 on a survey asks, Are you male or female? You could assign to male the value of 1 and to female the value of 2. These codes (1 and 2) are arbitrary; they could be anything that makes sense to the research team. The codebook is the document that lets everyone know that male = 1 and female = 2.The typical convention for most survey development tools is to assign the first response option in a list the code of 1, the second a code of 2, and so on. For example, a response list of racial/ethnic options might include White, Black, Asian or Pacific Islander, Native American or Alaskan Native, African American, Mixed Race, Other and Decline to State. The first response option entered, White, would be coded 1; Black would be coded 2; and so on, with Decline to State being assigned a code of 8. Some questions are precoded. For example, if you ask respondents how many times in the past week they ate at fast-food restaurants, their zip code, or the year, in which they were born, the numbers they provided do not need to be translated further; thereof, no code value would be assigned to these responses. Similarly, open-ended text questions do not have code values assigned.Although codebooks are not necessary for data-entry purposes in web-based and mobile surveys (because the data file is created automatically the when respondents type in their answer), online survey programs include the option to create codebooks so that any researcher working on the survey project will be able to identify the codes associated with each response value. Codebook ContentsCodebooks vary widely in quality and the amount of information provided. typical codebook includes ID numbers, variable name, variable description, variable format (e.g., number, text, date), codes used to indicate nonresponse and missing data, the exact questions and skip patterns used in a survey, and other indications of the content and characteristics of each variable..Codebooks also may contain frequencies of response; survey objectives; concept definitions; a description of the survey design and methodology; a copy of the survey questionnaire (if applicable); and information on data collection, data processing, and data quality.