Week 8: Workshop 8- Clinical Trial Design (The Pharmacist)
AIM
To understand fundamental factors in clinical trial design.
To define stages in conducting a clinical trial.
LEARNING OUTCOMES
Be familiar with the range and types of clinical trial evaluation.
Appreciate how clinical trial information contributes to clinical governance, clinical guidelines and best
practice.
1-Case Report
Definition
An article that describes and interprets an individual case, often written in the form of a detailed story. Case
reports often describe:
Unique cases that cannot be explained by known diseases or syndromes
Cases that show an important variation of a disease or condition
Cases that show unexpected events that may yield new or useful information
Cases in which one patient has two or more unexpected diseases or disorders
Case reports are considered the lowest level of evidence, but they are also the first line of evidence, because
they are where new issues and ideas emerge. This is why they form the base of our pyramid. A good case
report will be clear about the importance of the observation being reported. If multiple case reports show
something similar, the next step might be a case-control study to determine if there is a relationship between
the relevant variables.
Examples
This case report was published by eight physicians in New York city who had unexpectedly seen eight male
patients with Kaposi’s sarcoma (KS). Prior to this, KS was very rare in the U.S. and occurred primarily in the
lower extremities of older patients. These cases were decades younger, had generalized KS, and a much
lower rate of survival. This was before the discovery of HIV or the use of the term AIDS and this case report
was one of the first published items about AIDS patients.
This case report is written by the patient, a physician who contracted SARS, and his colleague who treated
him, during the 2003 outbreak of SARS in Hong Kong. They describe how the disease progressed in Dr. Wu
and based on Dr. Wu’s case, advised that a chest CT showed hidden pneumonic changes and facilitate a rapid
diagnosis.
2. Case Control Study? Definition
A study that compares patients who have a disease or outcome of interest (cases) with patients who do not
have the disease or outcome (controls), and looks back retrospectively to compare how frequently the
exposure to a risk factor is present in each group to determine the relationship between the risk factor and
the disease.
Case control studies are observational because no intervention is attempted and no attempt is made to alter
the course of the disease. The goal is to retrospectively determine the exposure to the risk factor of interest
from each of the two groups of individuals: cases and controls. These studies are designed to estimate odds.
, Case control studies are also known as "retrospective studies" and "case-referent studies."
Examples
Patients with non-Hodgkin lymphoma (NHL) were matched with controls to compare their history of
autoimmune and chronic inflammatory disorders, markers of severity, and treatment. The study showed the
risk of NHL was increased in association with rheumatoid arthritis, primary Sjögren syndrome, systemic lupus
erythematosus, and celiac disease.
This study looked at the relation between risk of acute myocardial infarction and current or former smoking,
type of tobacco, amount smoked, effect of smokeless tobacco, and exposure to second-hand smoke.
3. Cohort Study
Definition
A study design where one or more samples (called cohorts) are followed prospectively and subsequent status
evaluations with respect to a disease or outcome are conducted to determine which initial participants’
exposure characteristics (risk factors) are associated with it. As the study is conducted, outcome from
participants in each cohort is measured and relationships with specific characteristics determined
Advantages
AIM
To understand fundamental factors in clinical trial design.
To define stages in conducting a clinical trial.
LEARNING OUTCOMES
Be familiar with the range and types of clinical trial evaluation.
Appreciate how clinical trial information contributes to clinical governance, clinical guidelines and best
practice.
1-Case Report
Definition
An article that describes and interprets an individual case, often written in the form of a detailed story. Case
reports often describe:
Unique cases that cannot be explained by known diseases or syndromes
Cases that show an important variation of a disease or condition
Cases that show unexpected events that may yield new or useful information
Cases in which one patient has two or more unexpected diseases or disorders
Case reports are considered the lowest level of evidence, but they are also the first line of evidence, because
they are where new issues and ideas emerge. This is why they form the base of our pyramid. A good case
report will be clear about the importance of the observation being reported. If multiple case reports show
something similar, the next step might be a case-control study to determine if there is a relationship between
the relevant variables.
Examples
This case report was published by eight physicians in New York city who had unexpectedly seen eight male
patients with Kaposi’s sarcoma (KS). Prior to this, KS was very rare in the U.S. and occurred primarily in the
lower extremities of older patients. These cases were decades younger, had generalized KS, and a much
lower rate of survival. This was before the discovery of HIV or the use of the term AIDS and this case report
was one of the first published items about AIDS patients.
This case report is written by the patient, a physician who contracted SARS, and his colleague who treated
him, during the 2003 outbreak of SARS in Hong Kong. They describe how the disease progressed in Dr. Wu
and based on Dr. Wu’s case, advised that a chest CT showed hidden pneumonic changes and facilitate a rapid
diagnosis.
2. Case Control Study? Definition
A study that compares patients who have a disease or outcome of interest (cases) with patients who do not
have the disease or outcome (controls), and looks back retrospectively to compare how frequently the
exposure to a risk factor is present in each group to determine the relationship between the risk factor and
the disease.
Case control studies are observational because no intervention is attempted and no attempt is made to alter
the course of the disease. The goal is to retrospectively determine the exposure to the risk factor of interest
from each of the two groups of individuals: cases and controls. These studies are designed to estimate odds.
, Case control studies are also known as "retrospective studies" and "case-referent studies."
Examples
Patients with non-Hodgkin lymphoma (NHL) were matched with controls to compare their history of
autoimmune and chronic inflammatory disorders, markers of severity, and treatment. The study showed the
risk of NHL was increased in association with rheumatoid arthritis, primary Sjögren syndrome, systemic lupus
erythematosus, and celiac disease.
This study looked at the relation between risk of acute myocardial infarction and current or former smoking,
type of tobacco, amount smoked, effect of smokeless tobacco, and exposure to second-hand smoke.
3. Cohort Study
Definition
A study design where one or more samples (called cohorts) are followed prospectively and subsequent status
evaluations with respect to a disease or outcome are conducted to determine which initial participants’
exposure characteristics (risk factors) are associated with it. As the study is conducted, outcome from
participants in each cohort is measured and relationships with specific characteristics determined
Advantages
