关键词: 体征和症状, 躯体型障碍, 未分化疾病, 医学无法解释的躯体症状, 诊断, 决策, 争鸣

Abstract: Undifferentiated disease is defined as medically unexplained physical symptoms or the disease which is still in the early stage and not clearly attributed to a specific system.In the diagnosis and treatment of such diseases，excessive medical resources are often consumed，resulting in more medical and social problems.This article summarizes the characteristics and over-diagnosis of undifferentiated diseases，then deeply analyzes four major factors（of patient-，physician-，medical examination techniques- and medical industry-related）associated with over-diagnosis，and proposes that shared decision making is an effective way to solve these over-diagnosis problems.In addition，to achieve effective shared decision making for intervening such diseases，clinicians should provide patients with professional advice，and deliver interventions based on fully considering the patient's demands as well as develop a contractual mode of physician-patient relationship.

Key words: Signs and symptoms, Somatoform disorders, Undifferentiated disease, Medically unexplained physical symptoms, Diagnosis, Decision making, Contending