Clinical Research

Dr Naveen PhuyalMBBS. MD

History

Medical research as an organized scientific discipline has just surfaced in last few decades.

The practice of this art however can be traced to almost 400 years back when Hippocrates related human disease to the environment on his treatise “ Airs, Waters and Places”.

James Lind and Scurvy (1747)

Edward Jenner vaccinating for prevention of Smallpox (1796)

John Snow and Cholera (1850)

Semmelweis’ hand hygiene study

Goldberger relating pellagra to maize diet (1915)

History

Fletcher relating beriberi to polished rice (1905)

They all were practicing epidemiology

Strong methodologies were developed later on in 1940s and 1950s

Community trials of fluoridation of water supplies

Cigarette smoking and lung cancer by Doll and Hill

Why research at all ?

To submit thesis/ dissertationPublish or Perish syndromeMedicine is still practiced and so many things yet to be known

Medicine is expanding we need more knowledgeAs qualified doctor we have obligation to art and science of medicine and we also have to contribute to this advancement.

Why should a doctor be trained to do medical research?

Clinical epidemiology is nothing but an extension of wise clinician’s intuitively explorative faculties.

However such extension of this faculty does not occur with learning and practicing medicine.

History of medicine is replete with instances in where the results based on unscientifically conducted research have been applied to the patients eg. Blood letting, Gastric freezing.

Why should a doctor be trained to do medical research?

Doctors are consumers of research done by others, applying their research to treat their own patients.

Our own research will be used by our colleagues who read our publications, in their clinical practice.

7 reasons

These 7 reasons act in sequence and make a working knowledge of ‘ medical research’ necessary for every doctors:1. Variability2. Generalisability/ Loss of external variablity3. Precision/ Sampling error4. Internal validity/ Bias/ Measurement Errors5. Indirect Associations/ Confounding6. Statistical significance / Clinical significance7. Selecting the correct research “Design”8. Reading and asking questions

Variability

All humans, healthy or sick, and their characteristics are different from each other.

Hence our clinical observations based on few subjects of our own practice may not be enough to be applied to all patients all over the world.

Generalisability

We cannot study the whole lot of subjects , we have to study samples.

Samples should be representative: if not results can not be generalized to the total population.

This is called as loss of external validity or loss of generalisability.

Precision/ Random or Sampling Error

Samples should be of adequate size to obviate the play of chance.

The role of chance has to be evaluated statistically.

Internal validity/Bias/Measurement Errors

Entire research is based on making correct measurements.

We should be able to accurately measure what we really intend to measure.

We need to be aware of places where such ‘measurement errors’ may come up.

Indirect association/ Confounding

We have to demonstrate that association in our research is not explained by ‘ indirect association’ due to a third factor.

Statistical and clinical significance We must consider primarily the clinical and public health

significance of our result and not go by “ statistical significance’

Design of the study

The design of our research work should be such that it is appropriate to answer the clinical/ public health question at hand.

Reading and asking

Research does not stop after our particular study has been done.

Every research opens up many more question, which need to be further answered.

Thank You