Both newly diagnosed diabetic patients and older diabetic patients are interested in knowing if they have complications from diabetes. What tests should be done to clarify the diagnosis? 1. Eyes: To clarify if you have diabetic eye disease. Preliminary examination: Go to ophthalmology to check vision and dilate the pupil to check the fundus. Further examination: for those with suspicious fundus lesions or those with preproliferative or proliferative retinopathy, further fundus fluorescence imaging should be done. 2. Heart: clarify whether there is concurrent coronary artery disease and hypertension Preliminary examination: standard 12-lead ECG, blood pressure in prone and standing position. Further examination: cardiac ultrasound, 24-hour ambulatory electrocardiogram and 24-hour blood pressure monitoring for suspected cardiovascular lesions. 3. Kidney: clarify whether there is diabetic nephropathy Preliminary examination: urine routine, urine microscopy, 24-hour urine albumin quantification or urine albumin to creatinine ratio, blood creatinine and urea nitrogen. Further examination: creatinine clearance measurement is feasible for those with renal lesions. 4. Neurological system: clarify whether there is diabetic neuropathy Preliminary examination: tendon reflexes of the limbs, blood pressure in the standing and lying position, tuning fork vibration sensation or nylon wire tactile sensation. Further examination: if neuropathy is suspected, nerve conduction velocity measurement and nociceptive threshold measurement will be performed. 5, foot: clarify whether there is diabetic foot lesion Preliminary examination: dorsal foot artery, posterior tibial artery pulsation and ischemic performance, skin color, whether there is breakage, ulceration, fungal infection, callus, fine hair loss, etc. Ask about abnormal sensory symptoms such as numbness, pain, and ankylosis of the foot. Further examination: for those with lower limb ischemia, Doppler ultrasonography, blood flow measurement, brachial artery and dorsalis pedis artery blood pressure ratio are feasible. 6.Blood biochemical examination:: clarify whether there is hyperlipidemia, hyperuric acid, and understand liver function Blood lipids (total cholesterol, triglycerides, LDL-C and HDL-C), uric acid, electrolytes, liver function, etc. 7.When type l diabetes is suspected For adolescents with high blood glucose and patients suspected of having possible type l diabetes, check islet cell antibodies, insulin antibodies and glutamic acid decarboxylase antibodies as well as blood insulin or C-peptide levels. 8. For patients with manifestations of insulin resistance, measure fasting blood insulin, etc. After completing the screening for complications, for patients without complications, in principle, patients with type 2 diabetes should be screened once a year. patients with type 1 diabetes should be screened once a year after 3-5 years if the first screening is normal.