Implement data blinding versions of the analysis dataset

[gorkang]

See: https://journals.sagepub.com/doi/10.1177/25152459221128319

The data blinding versions would have the DV column shuffled, and the rest of the dataset untouched, so the analysis can be prepared without knowing about the actual relationships of the IV with the DV.

Think about:

• a way to password protect the original dataset and link the password to the publication of the analysis plan?
• a way to log the access to the original dataset

[gorkang]

Initial implementation done. Needs to be reviewed.