I have a large patient level covid-19 test dataset which is exceeding 400MBs. It is in excel format and loading it to Stata takes a long time. I was in fact timing it once and this took >2hours.

Next, I tried saving the file in csv and loading it to Stata and it only took less than 2 minutes to load the dataset into Stata.

My question is, what risks, in terms of data loss, exists when converting files to csv and loading into Stata? I have noticed date formats changing to strings, which is fixable. My concern is more about loosing information/changing quality of data.

Appreciate any thoughts on this.