Working with variables

Variables are the first thing you come across when you create a new project. The window is divided into two sections: On the left side you can add new variables, and on the right side you can create variable groups. You can easily drag-and-drop variables into groups. 

Data types

In PRJCTS there are five types of data types for variables. It is important to choose the correct data type as it can not be changed later. Here is an explanation of the different data types.

Categories

Category variables are used for structured and repeatedly used text data such as countries, colors, diagnoses, genders, etc. and can be used in statistical analysis and graphical presentations, whereas a text variable can not.

Numbers without decimals

Number without decimal variables are used for age groups, etc.

Numbers with decimals

Number with decimal variables are used for weight, etc.

Dates

Date variables contain dates and are formatted as dates. If dates have been entered as text in your Excel file with “.”, Excel will not recognize the text as dates when you try to reformat. You must replace all “.” with “/” with the find and replace function and then reformat the cells to dates before importing – i.e. change “31.12.2020” entered as text in your file to “31/12/2020” and then reformat the cells from text data to dates. 

If you import a csv file you have to define the date format – i.e. 31-12-2020 adheres to the format %d-%m-%Y. A column with the header “Date of birth” should then be renamed date(%Y/%m/%d)#Date of birth.

Text 

Text variables is unique and unstructured data that cannot be used in statistical analysis or graphical presentations. 

In general, it is advised to limit the use of text variables in research projects because it can not be used in statistical analyses and graphical presentations.

Variable attributes

Fixed values

You and your collaborators can only select the values that you define in the list. To add more values, simply type in the new value in the list and click enter. You can drag and drop the values to change the order. This will change the order both in the data entry form and in the order the values appear in tables and graphs in the analyses.

Show as drop down

The category values will be shown in a drop down menu in the data entry form. This is suitable when there are many values.

Mandatory fields

The user must enter data / choose a value in order to save or update an entry.

Personal data

Access to personal data can be restricted for collaborators without permission to view and edit the raw data. 

See our guide on creating a new variable to learn more.