Types Of Clinical Trials AndIts Significance

Types Of Clinical Trials And Its Significance Clinical trials means medical research

studies involving people. They are divided into different stages, called phases. The

earliest phase trials might focus at whether a drug is safe or the side effects it

causes. A later phase trial aims to test and compare whether a new treatment is

better than existing ones.also checkwhy clinical trials are important in clinical

research.

Types of Classifications:

In one way of classification it is based on the behavior of researches:

• Clinical observational study: The investigators observe the

subjects and measure their outcomes. They don’t actively manage the

study.

• Intervention study: The investigators give the research subjects a

particular medicine to compare the treated subjects with those

receiving no treatment or the standard treatment. Based on

inferences the investigator measures the health changes if any.

The U.S. National Institutes of Health (NIH) organizes trials into five

different types:

• Prevention trials : It attempts to find better ways to prevent

diseases in people who were never susceptible or to prevent a disease

from returning. These approaches include medicines, vitamins,

vaccines, minerals, or lifestyle changes.An example of a

prevention trial is the IBIS 2 breast cancer prevention trial.

• Screening trials: The best way to detect certain diseases or health

conditions. The study of causes and patterns of disease is called

epidemiology. Most epidemiological studies are observational

studies.There are three types of observational studies

– cohort studies,case control studies and cross sectional

studies.

• Diagnostic trials : To find better alternative for diagnosing a

particular disease or condition. For example to study tests or

procedures that could be used to identify cancer more accurately.

Diagnostic trials usually include people who have signs or symptoms

of the disease.

• Treatment trials : It efforts testing experimental treatments, new

combinations of drugs, or new approaches to surgery or radiation

therapy. They are conducted with diseased people as test subject.

They aim answering specific questions about and evaluate the

effectiveness of a new treatment or a new drug or a new approach of

using a standard treatment.

• Supportive care trials : It attempts find the quality of trials. It aims

finding ways to improve the comfort and quality of life for individuals

with a chronic illness.

• Expanded access trials : Also known as compassionate use trials. It

provides partially tested, unapproved therapeutics to a small number

of patients who have lost all realistic options. Usually this involves

disease for which no effective therapy has been yet approved.

A third classification is whether the trial design allows changes based

on data accumulated during the trial.

• Fixed trials : It considers existing data only during the trial’s design,

and does not modify the trial after it begins and even not assess the

results until the study is complete.

• Adaptive clinical trials: This use existing data to design the trial and

then use inferred results to modify the trials as it proceeds.

Modifications include dosage, sample size, drug undergoing trial,

patient selection criteria and “cocktail” mix. Adaptive trials often

employ a Bayesian experimental design to assess the trial’s progress.