The starting point for safety is the national licencing authority – each country’s DGCA (Directorate-General for Civil Aviation). If the DGCA’s safety oversight is strong, the airlines of that country will be as safe as anywhere else. If the DGCA is weak or deficient, you may still of course have individual airlines with a strong safety culture but there may be others that slip through the net. The US and the EU both maintain blacklists and watchlists which are a strong incentive to individual states to smarten up their act.
One country springs to mind (its name begins with In and finishes with ia and it’s not India) about which more questions are asked than most. There may be others. But always remember – a million-to-one chance of getting wiped out is twice as bad as two million to one, but it’s still pretty good odds.