Temperatures of the digits can be measured as low as 90 degress Farenheit. Noninvasive vascular tests that are occasionally used to evaluate patients with Raynaud's disease include digital pulse volume recordings and measurement of digital systolic blood pressure and digital blood flow. Nailfold capillary microscopy is normal in patients with Raynaud's disease, whereas deformed capillary loops and avascular areas are present in patients with connective tissue disorders or other causes of digital vascular occlusion.

Determinations of the erythrocyte sedimentation rate and titers of antinuclear antibody, rheumatoid factor, cryoglobulins, and cold agglutins are useful to exclude specific secondary causes of Raynaud's phenomenon. Angiography is not necessary to diagnose Raynaud's phenomenon but may be indicated in patients with persistent digital ischemia secondary to atherosclerosis, thromboembolism, or thromboangiitis obliterans to identify a cause that may be treated effectively with a revascularization procedure. Past medical history is most important in making the diagnosis of Raynaud's disorder.