The value of medical research derives from its ability to impact further research and medical practice. Medical knowledge synthesis, bridging the gap between current research, future research and medical practice, is a rapidly changing industry. The expanding mass of medical information makes knowledge synthesis evermore essential to enable and inform evidence-based decision-making. Systematic reviews (SRs), clinical practice guidelines (CPGs), textbooks and electronic information tools are the dominant modes of medical knowledge synthesis.
Over the last fifty years, the number of systematic reviews and guidelines has increased more rapidly than the publication of new original research. High standards have been developed for SRs and CPGs, but they are not widely adopted. Some medical research questions are over-covered by multiple and sometimes contradictory systematic reviews and guidelines, while others questions are not covered at all by high-quality knowledge synthesis. Until recently, textbooks were, with colleagues, the main source of information for clinicians. They have been supplanted by the Internet and point-of-care resources. The integration of high quality and up-to-date evidence varies across textbooks and electronic information tools.
This white paper summarizes important and practical information on Systematic Reviews (SRs), Clinical Practice Guidelines (CPGs), medical textbooks and point-ofcare resources, discusses their interrelationship and evolution, and the evidence on their quality, use and impact on medical practice.
Using two hundred years of national and Massachusetts data on medical care and health, we examine how central medical care is to life expectancy gains. While common theories about medical care cost growth stress growing demand, our analysis highlights the importance of supply side factors, including the major public investments in research, workforce training and hospital construction that fueled a surge in spending over the 1955-1975 span. There is a stronger case that personal medicine affected health in the second half of the twentieth century than in the preceding 150 years. Finally, we consider whether medical care productivity decreases over time, and find that spending increased faster than life expectancy, although the ratio stabilized in the past two decades.