Randomization is a fundamental concept in clinical research that refers to the process of randomly assigning participants to different study groups. Randomization is a crucial tool for reducing bias and ensuring that study results are unbiased and statistically valid. Randomization involves assigning participants to study groups in a way that is not influenced by any factors that could potentially affect the outcome of the study. This is typically done using a computer-generated randomization sequence or a random number table. There are several benefits to using randomization in clinical research. First, it helps to ensure that the study groups are comparable in terms of baseline characteristics, such as age, sex, and disease severity. This reduces the risk of bias and confounding factors that could impact study results. Second, randomization helps to ensure that any observed differences between the study groups are due to the intervention being tested, rather than other factors. This is critical for establishing causality and determining whether a particular intervention is effective. Finally, randomization helps to ensure that the results of the study are statistically valid. By randomly assigning participants to study groups, researchers can calculate the probability of obtaining the observed results by chance alone, which helps to determine the significance of the findings. In summary, randomization is a critical tool for ensuring the validity and reliability of clinical research results. By reducing bias and ensuring that study groups are comparable, randomization helps to establish causality and determine the effectiveness of medical interventions.

1. Welcome
Randomization – From The Technical Front
Monika Yadav
M Pharmacy
Student ID :- 007/012023
5/5/2023
www.clinosol.com | follow us on social media
@clinosolresearch
1

2. Index
 Introduction
Objective
Randomization Methods
 Background
What Is Randomization
Principle
Advantages and disadvantages
5/5/2023
www.clinosol.com | follow us on social media
@clinosolresearch
2

3. Randomization – From The Technical Front
Study participants are randomly assigned to one or more
groups that receive (different types of) an intervention,
known as the “treatment group” or groups, and a comparison
group that does not receive any intervention. Researchers
then measure the outcomes of interest in the treatment and
comparison groups. Randomized evaluations make it
possible to obtain a rigorous and unbiased estimate of the
causal impact of an intervention; in other words, what
specific changes to participants’ lives can be attributed to the
program. They also allow researchers and policymakers to
tailor their research designs to answer specific questions
about the effectiveness of a program and its underlying
theory of change.
5/5/2023
www.clinosol.com | follow us on social media
@clinosolresearch
3

4. To review and describe randomization
techniques used in clinical trials,
including simple, block, stratified, and
covariate adaptive techniques.
5/5/2023
www.clinosol.com | follow us on social media
@clinosolresearch
4
Objective: Background:
Clinical trials are required to establish treatment efficacy of
many athletic training procedures. In the past, we have
relied on evidence of questionable scientific merit to aid the
determination of treatment choices. Interest in evidence-
based practice is growing rapidly within the athletic training
profession, placing greater emphasis on the importance of
well-conducted clinical trials. One critical component of
clinical trials that strengthens results is random assignment
of participants to control and treatment groups. Although
randomization appears to be a simple concept, issues of
balancing sample sizes and controlling the influence of
covariates a priori are important. Various techniques have
been developed to account for these issues, including block,
stratified randomization, and covariate adaptive techniques.
Randomization
Methods:-
1. Simple Randomization
2. Unequal Allocation Randomization
3. Stratified Randomization
4. Blocked Randomization

5. Advantages:
Athletic training researchers and scholarly clinicians can use
the information presented in this article to better conduct and
interpret the results of clinical trials. Implementing these
techniques will increase the power and validity of findings of
athletic medicine clinical trials, which will ultimately improve
the quality of care provided.
5/5/2023
www.clinosol.com | follow us on social media
@clinosolresearch
5
What Is Randomization?
Randomization is the process of assigning participants to treatment and control groups, assuming that each
participant has an equal chance of being assigned to any group. Randomization has evolved into a
fundamental aspect of scientific research methodology. Demands have increased for more randomized
clinical trials in many areas of biomedical research, such as athletic training. In fact, in the last 2 decades,
internationally recognized major medical journals, such as the Journal of the American Medical
Association and the BMJ, have been increasingly interested in publishing studies reporting results from
randomized controlled trials.

6. Principle
The principle of randomization involves the
allocation of treatment to experimental
units at random to avoid any bias in the
experiment resulting from the influence of
some extraneous unknown factor that may
affect the experiment.
5/5/2023
www.clinosol.com | follow us on social media
@clinosolresearch
6
Simple randomization means that participants have an equal chance of
being allocated to different treatment groups. This method increases
statistical power and meets the assumption of equipoise in the randomly
allocated groups.
Unequal Allocation Randomization: Unequal allocation randomization
means randomly assigning participants into disproportionately sized
groups. The acceptable ratios for unequal allocation are 2:1, 3:1, and 4:1
controls to cases. This method is useful for studying rare outcomes,
adverse events, or emerging therapies. This method may lead to
violations of equipoise.
Stratified Randomization: Stratified randomization means randomly
assigning participants to treatment groups based on predefined and
objective characteristics called strata. Each stratum is randomly allocated
to treatment groups.
Blocked Randomization: Blocked randomization is feasible in smaller
studies. Participants are randomly assigned to treatment groups in small
"blocks" of four or six participants. This method ensures that there are
equally sized groups and it also meets the assumption of equipoise.
Randomization methods in experimental
research designs Simple Randomization:

7. Advantages and disadvantages of randomised control study design
5/5/2023
www.clinosol.com | follow us on social media
@clinosolresearch
7
Advantages of randomised control trial study design:
•Comparative:
• One treatment is directly compared to another to establish superiority.
• This study design can make causal inferences, i.e. it is the strongest
empirical evidence of a treatment's efficacy
•Minimises bias:
• Randomisation minimises allocation bias and selection bias
• Blinding minimises performance bias
• Double-blinding minimises assessment bias
• Allocation concealment minimises both performance and assessment
bias
• Prospective design minimises recall error and selection bias
•Minimises confounding factors:
• Randomisation minimises confounding due to unequal distribution of
prognostic factors
• Randomisation makes groups comparable according both known and
unknown factors
• Blocked randomisation makes groups comparable
within known confounding factors
•Statistical reliability
• Statistical test of significance is readily interpretable when the study is
randomised
• Sample size - when adequately powered- avoids both Type 1 error
(where the null hypothesis is incorrectly rejected) and Type 2 error
(where the null hypothesis is incorrectly accepted)
•Publishable
• Considered the gold standard: more publishable
•Disadvantages of randomised control trial study design:
•Logistics:
• Power calculation might demand vast samples size, which require more
resources from the investigators
• Validity requires multiple sites, which will be difficult to manage
• Long trial run time may result in the loss of relevance as practice may
have moved on by the time the trial is published
•Statistics
• A disadvantage of block randomization is that the allocation of
participants may be predictable and result in selection bias when the
study groups are unmasked
•Applicability
• Trials which test for efficacy may not be widely applicable. Trials
which test for effectiveness are larger and more expensive
• Results may not always mimic real life treatment situation (e.g.
inclusion / exclusion criteria; highly controlled setting)
•Ethical limitations
• Randomisation requires clinical equipoise: one cannot ethically
randomise patients unless both treatments have equal support in the
clinical community
• Informed consent is often impossible
• Some research cannot be ethically performed as an RCT
(classically, RCT of the effects of parachutes on the survival of sky-
divers)

8. REFERENCES…
• Domanski M, Mckinla . A Handbook for the 21st century. Philadephia, PA: Wolters Kulwer; 2009.
Successful randomized trails. [Google Scholar] [Ref list]
• Frane JW. A method of biased coin randomization, its implementation and validation. Drug Inf
J. 1998;32:423–32. [Google Scholar]
• Altaman DG, Bland JM. How to use randomize. BMJ. 1999;319:703–4. [PMC free
article] [PubMed] [Google Scholar]
• Altaman DG, Bland JM. Statistics notes. Treatment allocation in controlled trails: Why
randomize? BMJ. 1999;318:1209. [PMC free article] [PubMed] [Google Scholar]
• SAS/Stat User's Guide, version 9.2. Cary, NC: SAS Institute Inc; 2009. SAS institute Inc. [Google
Scholar]
• Domanski M, Mckinla . A Handbook for the 21st century. Philadephia, PA: Wolters Kulwer; 2009.
Successful randomized trails. [Google Scholar]
• Stang, Andreas. "Randomized controlled trials—an indispensible part of clinical
research." Deutsches Ärzteblatt International 108.39 (2011): 661.
5/5/2023
www.clinosol.com | follow us on social media
@clinosolresearch
8

9. Thank You!
www.clinosol.com
(India | Canada)
9121151622/623/624
info@clinosol.com
5/5/2023
www.clinosol.com | follow us on social media
@clinosolresearch
9