Implementations of MDSSs have been shown to reduce practice variability and improve outcomes. Over the last few years, the evolution in decision-making systems is proceeding with an extension of knowledge and the decisional processes underlying this knowledge. Best practice must be an organizational and process oriented concept to achieve adoption and consequently outcome improvements. The first step in how decision support systems can be re-examined and improved may be with incorporating new and unambiguous knowledge with a clear scientific reference. Evaluating these improved systems implies evaluating physicians' adoption, compliance with guidelines, and impact on outcomes. A second important building block is to adopt clear medical concepts and classifications. Because the use of medical data for cooperative care is necessary to improve the quality of care, the patient-centered electronic health care documentation is needed. The study covered over 100 researches conducted in the field of Medical Decision Support system (MDSS). However, the research was not limited to simply MDSS. The field of MDSS has evolved out of Information technology and medical informatics. The key concepts relating to current MDSS systems were developed and presented in the literature prior 1976. But the most monumental research was conducted by Miller (1994) and his study acts as the foundational study for this research.