These values are usually filled in automatically in the data entry program where the not applicable question has been omitted. In SPSS this will be automatically coded as system missing (a dot). the question is not applicable), then the variable is left blank. If the missing value results from a correct missing detail (i.e. For a missing date it is best to use a date from the distant past as a value for the incorrect missing value (usually the date uk-uk-YYYY is used for this). Two types of missing valuesĪ missing value resulting from an erroneously missing detail (omission or refusal to answer the question, etc) is usually coded with highest possible out-of-range value. If the item contains a conditional question, that is, where the response is dependent on the answer to a previous question, then the “not applicable value” is also potentially possible. Missing values are not possible for this type of question, as it is impossible to distinguish between “response categories missed” and “response category not endorsed”. The values for these variables may be either 1 or 0, if selected or not selected, respectively. Multiple choice questions (like choose all your sports activities) allowing multiple answers need to be split up in the codebook into as many variables as there are response categories. Please consult your research data management department for additional clinical database requirements. In case of clinical studies, standards should be applied wherever possible, for example by using standard case report forms from the Castor Form Exchange. Suffixes often indicate the wave of data in longitudinal studies, the form of a question or other such information.(Guide to Social Science Data Preparation and Archiving). Breakfast may then be BENU while lunch is LUNU and so on. For example, all variables having to do with nutrition may have the root NU. A prefix-root-suffix system could be used to systematically name variables. The names should be long enough to be meaningful but short enough to ensure that they are easy to handle. Variable names MUST consist of one string only (letters, numbers and underscores) and should not include more than 64 characters. Tips for naming variablesĪ unique unambiguous name should be given to each variable. Note that the details of a codebook partly depend on the used database program.
0 Comments
Leave a Reply. |