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Codebook (Data Dictionary)

When creating a database, it is important to create a codebook that identifies and explains the data. Below you will find database sample 1 and its codebook.

Database Sample 1

Codebook Sample 1

When creating your own codebook, please consider some of these basic tips.


  1. Shouldn't start with a number
  2. Should be one word
  3. The more meaningful, the easier to remember
  4. Length can be as long as necessary (but preferably shorter)


  1. Complete description of the variable
  2. Can be the actual question posed in the questionnaire


  1. Specify the type of variable (numeric, character, etc)

Values or Characteristics

  1. If it is ordinal (such as a Likert scale, 1=always, 2=sometimes, 3=never)
  2. If nominal (such as race) --> specify what each number represents
  3. If numerical --> should list how many decimal spaces
  4. If it applies, list the minimum and maximum