Clinical Trials in Clinical Research

Clinical Trials are part of clinical research and at the heart of all medical advances. Clinical Trials look at new ways to prevent, detect, or treat diseases under study. Treatments might be new drugs or new combinations of drugs, new surgical procedures or devices, or new ways to use existing treatments.

Goal of Clinical Trials

The goal of clinical trials is to determine if a new test or treatment works and is safe. Clinical trials can also look at other aspects of care, such as improving the quality of life for people with chronic illness.

Clinical Trials in Clinical Research: Definitions

Clinical Research

Clinical research is a medical research that involves people to test new treatments and therapies.

Clinical Trials

A research study in which one or more human subjects are prospectively assigned to one or more interventions (which may include a placebo or other control) to evaluate the effects of those interventions on health-related biomedical or behavioural outcomes.

Placebo

A placebo is a pill or liquid that looks like the new treatment but does not have any treatment value from active ingredients.

Protocol

A protocol is a carefully designed plan to safeguard the participants’ health and answer specific research questions.

Principal Investigator

A principal investigator is a doctor who leads the clinical research team and, along with the other members of the research team, regularly monitors the study participants’ health to determine the study’s safety and effectiveness.

Healthy Volunteer

A healthy volunteer is a person with no known significant health problems who participates in clinical research to test a new drug, device, or intervention.

Inclusion/ Exclusion Criteria

Inclusion/ exclusion criteria are factors that allow someone to participate in a clinical trial are inclusion criteria. Those that exclude or do not allow participation are exclusion criteria.

Informed consent explains the risks and potential benefits of a clinical trial before someone decides whether to participate.

Patient Volunteer

A patient volunteer has a known health problem and participates in research to better understand, diagnose, treat, or cure that disease or condition.

Randomization

Randomization is the process by which two or more alternative treatments are assigned to volunteers by chance rather than by choice.

Single or Double Blind Studies

Single or double-blind studies (also called single or double-masked studies) are studies in which the participants do not know which medicine is being used, so they can describe what happens without bias.

Clinical Trials Biostatistics

Phases of Clinical Trials

Clinical trials are conducted in phases. The trials at each phase have a different purpose and help researchers to answer different questions.

  • Phase-I Trials: an experimental drug or treatment in a small group of people (20 to 80) for the first time. The purpose is to evaluate its safety and identify side effects.
  • Phase-II Trials: The experimental drug or treatment is administered to a larger group of people (100 to 300) to determine its effectiveness and to further evaluate its safety.
  • Phase-III Trials: The experimental drug or treatment is administered to large groups of people (1000 to 3000) to confirm its effectiveness, monitor side effects, and compare it with standard or equivalent treatments.
  • Phase-IV Trials: After a drug is licensed and approved by the FDA (Food and Drug Administration), researchers track its safety, seeking more information about its risks, benefits, and optimal use.

Types of Clinical Trials

  • Diagnostic Trials: Determine better tests or procedures for diagnosing a particular disease or condition.
  • Natural History Studies: Provide valuable information about how disease and health progress.
  • Prevention Trials: Look for better ways to prevent a disease in people who have never had the disease or to prevent the disease from returning.
  • Quality of Life Trials (or Supportive Care Trials): Explore and measure ways to improve the comfort and quality of life of people with a chronic illness.
  • Screening Trials: Test the best way to detect certain diseases or health conditions.
  • Treatment Trials: Test new treatments, new combinations of drugs, or new approaches to surgery or radiation therapy.

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Normal Probability Distribution MCQs 13

Test your understanding of Normal and Standard Normal distribution with these key MCQs. The Quiz Normal Probability Distribution MCQs covers probabilities, Z-scores, percentiles, transformations, and real-world applications. This Normal Probability Distribution MCQs Quiz is perfect for:

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    Includes detailed solutions for concepts like empirical rule, quartiles, mean deviation, and CLT. Boost your stats skills now!
Online Normal Probability Distribution MCQs with Answers

Online Normal Probability Distribution MCQs with Answers

Online Multiple Choice Type Questions about Normal Probability Distribution with Answers

1. If $Y=5x+10$ and $X$ is N(10, 25), then mean of $Y$ is

 
 
 
 

2. The probability $P(Z\le 1.96)$ is approximately

 
 
 
 

3. If $X \sim N(10, 4)$ and $Y\sim N(15, 9)$ are independent, what is the distribution of $X+Y$?

 
 
 
 

4. Given a random variable $X$ which is normally distributed with a mean and variance both equal to 100. The value of the mean deviation is approximately equal to

 
 
 
 

5. If $X\sim N(\mu, \sigma^2)$ then $Z=\frac{X-\mu}{\sigma}$ follows

 
 
 
 

6. If $Z$ is a standard normal variate, then $P(-1.645 \le Z \le 1.645)$ is equal to

 
 
 
 

7. In a normal distribution mean is 100 and the standard deviation is 10. The values of points of infection are:

 
 
 
 

8. If $X$ is a normal variate with mean 20 and variance 1.6. The respective values of $\beta_1$ and $\beta_2$ are

 
 
 
 

9. If $X$ is a normal variate with mean 50 and standard deviation 3, the value of the quartile deviation is approximately equal to

 
 
 
 

10. If a normal distribution with $\mu=200$ have $P(X> 22.5)=0.1587$ then $P(X<175)$ equal to

 
 
 
 

11. If $Z$ is a standard normal variate, then $P(|Z| < 1.96)$ is equal to

 
 
 
 

12. For a normal distribution with $\mu = 10, \sigma = 2$ the probability of a value greater than 10 is

 
 
 
 

13. If $X$ is a normal random variable with mean $\mu=50$ and standard deviation $\sigma = 7$, if $Y=x-7$ then standard deviation of $Y$ is

 
 
 
 

14. If $Z$ is a standard normal variate, then $P(-2.33\le Z \le 2.33)$ is equal to

 
 
 
 

15. If $X$ is $N(100, 5)$ the fourth central moment is

 
 
 
 

16. Given a normal distribution with $\mu=100$ and $\sigma^2=100$, the area to the left of 100 is

 
 
 
 

17. A normal distribution has the mean $\mu=200$. If 70% of the area under the curve lies to the left of 220, the area to the right of 220 is

 
 
 
 

18. A random variable has a normal distribution with the mean $\mu=400$. If 8% of the area under the curve lies to the left of 500, the area between 400 and 500 is

 
 
 
 

19. The 99th percentile of the standard normal distribution is closest to:

 
 
 
 

20. If $Z$ is a standard normal variate, then $P(-2.575\le Z \le 2.575)$ is equal to

 
 
 
 


  • If $Z$ is a standard normal variate, then $P(-1.645 \le Z \le 1.645)$ is equal to
  • If $Z$ is a standard normal variate, then $P(-2.33\le Z \le 2.33)$ is equal to
  • If $Z$ is a standard normal variate, then $P(-2.575\le Z \le 2.575)$ is equal to
  • If $Z$ is a standard normal variate, then $P(|Z| < 1.96)$ is equal to
  • For a normal distribution with $\mu = 10, \sigma = 2$, the probability of a value greater than 10 is
  • Given a random variable $X$ which is normally distributed with a mean and variance both equal to 100. The value of the mean deviation is approximately equal to
  • If $X$ is a normal variate with mean 50 and standard deviation 3, the value of the quartile deviation is approximately equal to
  • In a normal distribution mean is 100 and the standard deviation is 10. The values of points of infection are:
  • If $X$ is a normal variate with mean 20 and variance 1.6. The respective values of $\beta_1$ and $\beta_2$ are
  • If $X$ is $N(100, 5)$, the fourth central moment is
  • A normal distribution has the mean $\mu=200$. If 70% of the area under the curve lies to the left of 220, the area to the right of 220 is
  • Given a normal distribution with $\mu=100$ and $\sigma^2=100$, the area to the left of 100 is
  • If a normal distribution with $\mu=200$ have $P(X> 22.5)=0.1587$ then $P(X<175)$ equal to
  • A random variable has a normal distribution with the mean $\mu=400$. If 8% of the area under the curve lies to the left of 500, the area between 400 and 500 is
  • If $Y=5x+10$ and $X$ is N(10, 25), then mean of $Y$ is
  • If $X$ is a normal random variable with mean $\mu=50$ and standard deviation $\sigma = 7$, if $Y=x-7$ then standard deviation of $Y$ is
  • If $X\sim N(\mu, \sigma^2)$ then $Z=\frac{X-\mu}{\sigma}$ follows
  • The probability $P(Z\le 1.96)$ is approximately
  • The 99th percentile of the standard normal distribution is closest to:
  • If $X \sim N(10, 4)$ and $Y\sim N(15, 9)$ are independent, what is the distribution of $X+Y$?

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Normal Distribution Quiz 12

Test your understanding of the Normal Distribution Quiz with this 20-question MCQ Test! Perfect for statisticians, data analysts, and students preparing for exams or job interviews. Covers key concepts such as mean, variance, standard deviation, Z-scores, and probability under the normal distribution. Check your answers and sharpen your statistical skills today! Let us start with the Online Normal Distribution Quiz now.

Online Normal Distribution Quiz with Answers
Please go to Normal Distribution Quiz 12 to view the test

Online Normal Distribution Quiz with Answers

  • A random variable $X$ is normally distributed with $\mu=70$ and $\sigma^2=25$. The third moment about the arithmetic mean is
  • For the standard normal distribution $P(Z > mean)$ is
  • Given a standardized normal distribution (with a mean of zero and a standard deviation of one), $P(Z<variance)$ is equal to
  • The area to the left of $(\mu + \sigma)$ for a normal distribution is approximately equal to
  • The median of a normal distribution corresponds to a value of $Z$ is ———.
  • The mean and standard deviation of the standard normal distribution are, respectively:
  • In a standard normal distribution, the area to the left of $Z=1$ is
  • The semi-interquartile range for a standard normal random variable $Z$ is
  • If $X\sim N(\mu, \sigma^2)$ then $\mu_4$ is equal to
  • If $X\sim N(\mu, \sigma^2)$ then $\beta_2$ is equal to
  • $P(\mu – \sigma < X <\mu + \sigma)$ is equal to
  • In a normal curve $\mu \pm 2\sigma$ covers
  • In $X$ is $N(\mu, \sigma^2)$, the percentage of the area contained within the limits $\mu\pm 3\sigma$
  • Most of the area under the normal curve with parameter $\mu$ and $\sigma$ lies between
  • The probability density function of the standard normal distribution is
  • The equation of the normal frequency distribution is
  • If $X$ is $N(\mu, \sigma^2)$ and if $Y=a+bX$ then mean and variance of $Y$ are, respectively:
  • For a normal distribution with mean $\mu$ and standard deviation $\sigma$
  • The normal probability distribution with mean $np$ and variance $npq$ may used to approximate the binomial distribution if $n\ge 50$ and both $np$ and $nq$ are
  • In a normal distribution, $Q_1=20$ and $Q_3=40$ then the mean is equal to

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