Lifelines variables are organized per theme in 13 main sections and ~230 subsections.
The 13 sections are:

1. Children & adolescents
2. Demographics
3. Diseases & Symptoms
4. Elderly (variables that were specifically collected in participants aged 65+ years old)
5. Family health
6. Lifestyle & environment
7. Medical treatment
8. Mental health
9. Nutrition
10. Physical state
11. Reproduction & development
12. Wellbeing & subjective health
13. Secondary & linked variables

Note that some subsections could fall under more than one section (i.e., “alcohol use” could be seen as a subsection of “lifestyle” or of “nutrition”, and “mental illness” could fall under “diseases & symptoms” or “mental health”). Similarly, individual variables may fit in more than one subsection. Lifelines always asigns a primary section and subsection to a variable, but may asign a second, alternative (sub)section to facilitate the findability of the variable in the online data catalogue.

Some Lifelines variables are provided by default in every issued dataset. As a result, these variables are not visible in the data-catalogue. An overview of the default variables can be found here.

Note that we may occasionally change a variable name, if there is a valid reason to do so (i.e. the original name is deemed confusing, too informal, unexpected, inconsistent, or incorrect). You may find a full list of changed variable names following this link: changed variable names.

Seldomly, we find variables that contain mistakes or inconsistencies. Most of the time these mistakes or inconsistencies will be corrected, but not always. You may find a full list of unfixable variables following this link: unfixable variables.