Evidence Based Medicine, Hierarchy of evidence

Evidence Based Medicine
Evidence based medicine (EBM) is an approach to medical practice that consists of the use of results of documented previous research in order to treat patients in the most accurate and efficient way possible. Even though modern medicine is profoundly based on empirical (scientifically proven by experiment) facts, Evidence Based Medicine extends further, rating the findings from the experiments by different measures (for example, the number of people the trial was performed on, the randomness of the testing etc.). This classification allows a researcher to yield the strongest, most reliable results one can work with. The results of randomized controlled trials and meta-analysis will be considered the strongest, most recommended evidence to rely on, while the researches that are considered to have “weaker” or results which are less credible will be case-controlled studies or experiments with an unknown origin.

The main concept of evidence-based medicine is to prove that medical practice should be most definitely based on solid, reliable, carefully gathered evidence, rather than on the treating physician’s personal knowledge or experience. This approach supports the belief that one may never fully know the extent of the clinician’s knowledge on a certain subject, nonetheless be able to assess it, and therefore the solid facts should always be the main guideline to treatment, whether discussing medical education, the treatment of individuals, or establishing policies that may concern whole populations.

When gathering medical evidence, the method of choice is the Scientific Method. It standardizes the gathering of evidence, regardless of the type of evidence, by following a strict set of steps. The goal of this method is to test a given theory (hypothesis).

Guidelines of Medical Based Medicine
EBM guidelines are essentially documents that aim to guide decisions and criteria regarding practice, diagnosis, and decisions in various clinical instances. Modern medical guidelines are based on an examination of current evidence within the format of evidence-based medicine.

EBM Guidelines is an easy to use collection of clinical guidelines for primary and ambulatory care linked to the best available evidence. Continuously updated, EBM Guidelines follows the latest developments in clinical medicine and brings evidence into practice.

EBM Guidelines is designed to provide you with the information that a doctor needs in order to follow protocol and make informed decisions. Designed for use at the point of care, the guidelines are delivered in a format that makes its easy for a clinician to make a decision regarding treatment.

Guidelines, however, should not be taken as gospel. They should be used in almost every case, but it is also important that the practitioner takes into account the diversity of humans and must consider all treatment options for the appropriate situation.

Scientific databases
Scientific Database is organized and collective computerized data, which can be acquired and accessed for scientific purposes such as for research and for long-term stewardship. The scientific database allows the integration of new database sources and also lets old data be analyzed in different ways and methods, often making new scientific source in the process, always under strict discipline.

The following advantages of using scientific databases are that in general, a database can constantly be improve and evolve with the adding of new data by new researchers. Also with the increasing number of users the tendency of detecting and discovering wrong or corrupted data and correcting it increases significantly.

Also a very good advantage while using scientific database is the cost, it is generally cheaper to save data then rather relocating the data. It is known that in many cases factors such as population influences and change of weather and change in ecosystem makes data relocation pretty impossible no matter what is the cost of it.

The progress of development of database is actually an evolutionary process, the data base will serves as a collective and dynamic community with a constant influx of users that at the end will make the database improve its data by the adding and editing and processing of new data constantly. [1]

Hierarchy of Medical Evidence and Evidence Pyramid
The hierarchy of medical of evidence is the distinguishable levels of evidence that can be obtained through various methods, and placing them in an order based on their credibility. For any given topic, the highest level of evidence is not always obtainable in which case a researcher would move down the pyramid. At the bottom of the pyramid is lab testing and animal research. While this is not necessarily an optimal method in order to validate a certain therapy, it can be used as an indicator about the adverse effects of a treatment, and may signal that the therapy will be injurious to the quality of evidence. In the middle of the evidence pyramid or case reports and case studies that outline treatment on patients, yet yield no verifiable evidence as they can only show causation, and not correlation. Furthermore, case studies use past medical documents to retrospectively look for evidence as opposed to cohort studies which prospectively follows a large number of patients in an attempt to find an outcome. In broad categories, all of the aforementioned evidence gathering categories is “unfiltered” in the sense that they have not gone through any evaluation process. They should not be regarded as being of very high in credibility. Randomized control testing is used to reduce bias and begins by someone (although not the researchers or the administration) selecting two separate groups. Dividing the two test groups in RCT is comparable to tossing a coin; it must be completely random. The goal is to make two evenly distributed groups on which the drug effects make little difference based on individual factors and two obtain results that are not influenced by assumptions of those conducting the study Systematic review is the Review of the RCT and is regarded as the key in evidence-based medicine. It is high on the Evidence Pyramid and is classified as “filtered” evidence, having undergone analysis. The steps are as follows:


 * 1) 	Choose one or several criteria about the research to be reviewed (Ex: Reduced heart rate?)
 * 2) 	Look for any data from the research that corresponds to the criteria
 * 3) 	Extract all relevant data
 * 4) 	All data acquired needs to be compared to the criteria set in point 1. If it corresponds to what you are looking for, it is a positive result.
 * 5) 	Analyze and compare the data.

Meta-Analysis is the quantitative and statistical analysis of the data acquired in all different methods of testing throughout the research period. All results are compared, and all corresponding results are put together statistically to reach more conclusions. The stronger correlation between different methods about one topic, for example the hearts response to a drug, the more likely it is to be true. This is the highest level of evidence and conclusions can be drawn one this evidence has been acquired.

Clinical trials - Types of clinical trials
Clinical trials are research studies that evaluate the efficiency of new medical approaches. All trials deal with very specific issues and attempt to answer particular questions. A study might, for example, try to provide better ways to prevent, screen for, diagnose or treat a disease. Trials follow strict protocols, explicitly describing all steps to be taken. Such a protocol would dictate the criteria used to choose suitable candidates for the purpose of the trial, what will be done in the study, its different parts and why they are crucial to the goal of the trial. Many trials, especially if they concern drugs, biological products or medical devices, have to be approved, monitored and reviewed by an Institutional Review Board (IRB). An IRB is a committee of physicians, statisticians, and other members of the community, entrusted with ensuring compliance with ethical parameters, protection of the participants’ welfare and rights, and relatively reasonable risk compared to possible benefits.[1]

Cohort Studies
Any group of people linked in some way is a cohort. In cohort studies researches follow and observe a group of patients, over time, who are undergoing a certain treatment or have an exposure. Researchers then compare the patients’ outcomes to a similar group who have not been exposed. An example of a cohort study would be, following a group of children from their birth, and record various information (exposures) about them. [5]


 * Clinical trials may be categorized according to various criteria.

Firstly, according to their objectives & the way they are organized:


 * Interventional (treatment) trials; aiming to test methods of treatment not yet approved
 * Prevention trials; attempting to prevent particular conditions or reoccurring of such
 * Observational trials; investigating health issues in greater groups of people (participants provide information, blood samples etc.)
 * Diagnostic and screening trials; attempting to find new and more effective ways of detecting and diagnosing medical conditions (e.g. better and more effective tests/procedures)

Secondly, according to the group of people likely to benefit from the study:

Finally, according to way of organization that could affect the participants (especially regarding the inclusion of a placebo group). The most common results of this classification are:
 * Therapeutic; the investigated treatment is expected to benefit the participants (as in the case of a drug trial)
 * Non-therapeutic; the trial is unlikely to benefit the participants but will yield information which could contribute towards further understanding a condition and future development of new treatments
 * Randomized; participants are assigned into separate groups randomly
 * Placebo; a substance similar in appearance to the experimental drug is used, not containing the active ingredients of the latter
 * Add-on; all participants receive existing therapy. Then, some receive the experimental drug, while others do not, or receive a placebo
 * Open label; both researchers and participants are aware of the administered drug
 * Blind; the participants are not aware of whether they are in the treatment or placebo group
 * Double blind; neither participants nor researchers know which participants are in the treatment and which in the placebo group, until the end of the study
 * Single-center; the study is carried out in a single location
 * Multi-center; the study is carried out in multiple locations (e.g. in different towns or even in more than one countries)[2] Controlled; a comparison (control) group is included. The latter receives a placebo, a different treatment, or no treatment at all.[3]