Background: The European Union implemented data privacy laws in mid-2018 and the state of California enacted a similar law several weeks later. These regulations affect medical data collection and analysis.
Methods: Here we investigate the effect of these laws on clinical trials through analysis of clinical trials recorded on ClinicalTrials.gov, the World Health Organization's International Clinical Trials Registry Platform and scientific papers describing clinical trials.
Results: The number of phase 1 and 2 trials in countries not adhering to data privacy laws rose significantly after implementation of these laws. The largest rise occurred in countries which are less free, as indicated by the negative correlation (-0.48, p=0.008) between the civil liberties freedom score of countries and the increase in the number of trials. This trend was not observed in countries adhering to data privacy laws nor in the paper publication record.
Conclusions: The implementation of data privacy laws is associated with a move of clinical trials to countries where people have fewer protections for their data.