Accreditation of hospitals , diagnostic labs and other health care organisations provide some degree of assurance of quality as they have to follow standardised processes as determined by accredited agencies. These processes are based on proven best practices and are frequently updated and also these organisations are audited frequently . Accreditation does not guarantee that there will no avoidable harm but the probability should be lower . 

Here are the links to the Accrediting agencies listing the organisations that have been accredited by them. Try and use one of the accredited organisation if you have one closer to you . However in case of Emergency please decide as appropriate. If you have any issue of a harm caused by one of the Accredited organisations you could also share it with the accrediting agency. 

Patients For Patient Safety Intiative has not reviewed any of these organisation and just providing you easy links. The list is continuously updated