Lessons Learned from Cohort Studies, and Hospital-Based Studies and Their Implications in Precision Medicine

Abstract

Advances in human genomics and cutting-edge technologies have created space for integrating personalized or precise medicine into the practice of medicine and thereby improving the public health. Achieving the goal of quantitatively improving the quality and effectiveness of health care for all requires both knowledge of classical, genomics, and pharmacogenomic studies carried out worldwide on different subsets of population. Since the disease outcome and therapeutic effectiveness may vary according to geographical areas, ethnicity, race, and genetic makeup, the complex pathways, including gene-environment, gene-drug, and gene-gene interactions, play a significant role in the development of disease as well as in determining an individual's response toward prescribed medicine. The decision-making process in selecting or identifying precise medicine via clinicians depends on the large effort carried out by researchers and pharmaceutical companies conducting clinical trials, cohort studies, and hospital-based retrospective and prospective studies (e.g., The Strengthening the Reporting of Genetic Association studies (STREGA) initiative builds on the STrengthening the Reporting of Observational Studies in Epidemiology (STROBE) study. However, the evidence based on gene-disease associations is fraught with certain methodological problems such as inadequate sample size, reporting of results, even from well-conducted studies, hampers the assessment of a study's strengths and weaknesses and hence the integration of evidence into clinical practice (Little et al., 2009).Precision Medicine Initiative, a research cohort, launched by NIH, including more than a million Americans, is one of the brilliant steps toward precision medicine which will contain genomic, clinical, and other health-related information. This U.S. Research Cohort may provide a platform for scientists to conduct rapid and efficient randomized trials that use cohorts and registries for further research (Baker et al., 2015). Appropriate decision making on the basis of previously established studies or trials and with available evidence in hand, based on genomic profiling have revolutionized the current paradigm of clinical practice. Now, the trend of giving importance to therapies rather than to diagnostics may need to be revisited to ensure and to speed up innovation in the area of personalized or precision medicine. ? 2017 Elsevier Inc.