The diagnosis of Raynaud's syndrome is generally straightforward. A doctor can make a diagnosis by evaluating your symptoms, characteristic skin changes visible during a physical examination, and your medical and family history. However, to determine whether the condition is primary (idiopathic) or secondary (associated with another underlying condition), additional tests such as blood tests, microscopic examination of nailfold tissue, and a cold stimulation test for Raynaud's syndrome are required.