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Protocol elements of a clinical trial

Protocol elements of a clinical trial
This is the basic, the basic trial operation, the basic trial infrastructure. But to perform, to execute this trial we need basic documentation. The main document which
contains the outline: The background information, the purpose, the objective of the research, the design, what subjects will be recruited, what will be accessed or evaluated during the research, its content, all the ethical framework, all the safety, all the legal requirements will be described and defined in a protocol. Elements of the protocol, as
we can read, includes: General information, background information, objectives / purpose, trial design , selections and withdrawal of subjects, treatment subjects, assessment of safety and efficacy.
The statistics, access to source documents, QA, QC, ethics, how to handle the data, the finance and insurance of the trial and even the publication policy. So what is a protocol? Protocol basically a study plan, a legal document, on which all clinical trials are based. The type of information and audience differs depending on the phase of the investigation. This plan is designed, as I mentioned before, to safeguard the health of the participants, as well as answer a specific research questions. It should describe the design, the objectives, the methodology, the organization of the trial. So who implement the protocol? As I mentioned many times, the ward investigator. Who is an investigator?
Investigator is an individual who direct a clinical investigation under whose immediate direction the drug or device is applied or administered to a subject. The investigator in one ward is the responsible of the research team, the leader of the team.
There are some investigators that also can be involved in the clinical research. This can defined as any other member who is directed and supervised by the PI, to perform activities described in the protocol.
So who implement the protocol? Who is responsible for the protocol? The sponsors. An individual who takes for an initiate a clinical investigation. A sponsor may be a company, a government institution, academic institution or a private organization.
Subjects, subjects are individuals who participates in a clinical study. If the individual, patient or healthy, enters a clinical investigation become a subject and this need to be addressed in the protocol.
So where to start? What is the research mechanics? Basically, the investigator should define the type of study to be conducted, the hypothesis, translated hypothesis into objectives, should establish the endpoint, should design the trial, should design, decide what is a treatment group.
Should decide what would be the active treatment controls, should decide whether this will be a prevention investigation, a diagnostic research, a screen research, a quality of life study, an observational trial, a prospective or retrospective interventional trial, will be compared against historical controls, will be proved the superiority of the investigational product or maybe either the non-inferiority or equivalence. Will be used control populations or placebo control? Will be blinded or unblinded? Is just to measure some timepoints during a pharmacokinetic study?
One of the key methods is the hypothesis, translated hypothesis into objectives. This is one of the most difficult part, but to be success in implementing the objectives, the investigator should be a specific, the objectives should be measurable, ordered, significant, and should follow a specific time.
Once this framework is established, then the investigator will define, decide, what is the proper way to evaluate the effectiveness in the target condition and population. What will be the safety concerns? What is more effective? Is this more effective than another intervention? Is the safety and efficacy limited to a particular sub-group of population? What is the base measure to evaluable safety and effectiveness? To do that, the investigator should define what are the endpoints, how to measure the objective? Why at this point should it be accepted and approved by the regulatory authority or by the local ethical committee? To make sense, you can use new points, you can have new endpoints evaluation methods, but you have to scientifically valid and prove it.
So this will be summarized in the the study design. The study design will contain all the info, all what I mentioned before. All the method, all the methodology, and the definition, in a summarized way.
So at the end of the day, the research mechanics will also relied on what others have done in the past to continue to improve what others has been done in the past. To do this, is necessary to refer to review articles and research databases like the Pubmed or go to websites like the FDA, or EMI which contains public information about clinical research done in the past or currently ongoing. There are other websites for references like you can see “”, “” or “” which contains a very detailed and very smooth, easy readings and definitions about clinical research.
Finally, the protocol will be, will be readed or reviewed by the many many people so make sure who is reading your protocol. Make sure who will define what is the end of the protocol. What will be the final document provided.
Thank you for your attention.

What is a protocol?

A protocol describes the objectives, design, methodology, population, statistical considerations, ethical conduct, and organization of a clinical trial.

In this video, Dr. Castro will explain the key components of a protocol and how to design a feasible clinical trial.

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Introduction to Translational Research: Connecting Scientists and Medical Doctors

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