Methods in vaccine effectiveness and safety studies: a critical need for vaccine confidence.

As currently designed, vaccineshave as their goal the conversion f a generally healthy but susceptible host, into a host protected gainst a disease (for which the vaccine is being administered) o which the host may be exposed to at a future date. To this nd, a high bar for effectiveness, efficacy, and safety of vaccines s appropriate. Interest in efficacy and safety is not confined to scintists and health care providers, but also to the general public. ndeed, absent data demonstrating both safety and efficacy, such accines will neither be recommended by physicians, nor utilized y the public. Measuring safety and effectiveness is not, however, nherently straightforward. Done correctly, increased confidence nd widespread adoption of a vaccine may ensue. Done poorly, or ncorrectly, years of misperceptions and “active disuse” of a vacine may result. Recent examples include vaccine safety fears and ontroversies regarding the possible occurrence of Guillian–Barre yndrome after pandemic influenza vaccine, or fears about autism pectrum disorders among intended recipients of MMR vaccines. hese controversies started with anecdotal observations, and proeeded to various types of study designs often of low ormisleading uality. Because the science ofmethods in vaccine safety and effeciveness continues to evolve, “gold standard” study design and ethods have not yet been widely disseminated and put into lace by scientific journals and routinely utilized by journal ediors and reviewers. Worse, the print and broadcast media often isinterpret or wrongly report such observations, decreasing pubic confidence in vaccines. As a result, confusion ensues and poorly esigned studies are published that add to the fears and confuion about a vaccine’s safety or efficacy. Indeed, recent papers nd commentaries on the “new decade of vaccines” have emphaized the importance of vaccine confidence, and the scientific and ocial challenges we face in developing and utilizing new vacines [1,2]. Sound study design methods for vaccine safety and ffectiveness are essential to physician and public confidence in accines. As a remedy for this situation, we are excited to announce a new ection for VACCINE entitled, “Methods in Vaccine Effectiveness nd Safety Studies.” In recent years, a confluence of circumstances as led to a proliferation of observational vaccine safety and ffectiveness studies. These include the widespread adoption of lectronic health records, increased interest among investigators n following large cohorts for epidemiologic studies on the influnces of vaccination on health, and many large vaccine safety nitiatives in the U.S. These include such representative initiatives s the Vaccine Adverse Event Reporting System (VAERS) [3], Vacine Safety Datalink (VSD) [4], Post-licensure Rapid Immunization