Thinking it may be helpful for me to explain all this, as I never heard about those coming from China to the USA in late 1990s. Maybe the employers are doing those in China nowadays too, but at my time, I never heard about it.
Background Check
There are background check, and sometimes there are employment history verification etc. Nowadays background check usually has two approaches: 1) The government database check, e.g., before someone get firearms, they usually need to run a check; 2) The second approach is via a commercial company (database) check. I did both. Actually recently I just did one when I am volunteering for the school.
Example 1: there are companies that do background check for employers. such as this one called Clariti (now it’s a part of GHRR). You may read this clariti background check reddit thread if needed. It seems to me they are mostly trying to verify past employment history as well. Note in the reference check, they could do similar check, if it’s just a call from HR. I do follow the instructions carefully when I do this sort of thing. Below is copy paste of some of the instructions.
Complete all fields.
Use your legal name and information and add any maiden or previous names to the additional names section.
Please provide all addresses where you have lived for the past 7 years.
Review your answers for accuracy and spelling.
If you have any questions or special circumstances you should call our office at before submitting this request.
My comment: sometimes I doubt the effectiveness of this sort of background check. But we still need to respect the process though, as this is quite common step before some employers can formally onboard someone.
Example 2: I did this one MACHS Fingerprinting Background Checks website twice as a requirement for my volunteer work for Ladue School. I think first time they came to LMS and fingerprinted people on site. Mostly recently I went to this place called IdentoGo (it looks like a private company, but they work with government agencies such as FBI for background check). I go there, did my fingerprints, and they sent my information to their backend for more processing. And they also sent back information to the Ladue School on the 2nd day. It seems they are pretty efficient in terms of processing.
Reference Check
I have done reference check for colleagues and friends from time to time. For that purpose, I usually make sure I get an updated resume, and also ask my colleague or friend what should I say (I usually say nice things).
Drug Test
For my 1st job, I did the drug test via the hair sample. More common drug test is via urine sample. I did urine sample a few times in my career, all for pre-employment drug testing. Again the need for drug test also varies by employer.