This document discusses quantitative and qualitative research methods used in medical research. It provides examples of quantitative research designs including observational studies like cross-sectional, case-control and cohort studies as well as experimental designs like randomized controlled trials. Key aspects of cohort studies are described such as their distinguishing features, examples of different types, and measures used to determine risk like relative risk and attributable risk.
Social and Preventive Medicine Classroom discussion topic on types of Epidemiological study designs available.
sole reference is Park text book 20th edition
Social and Preventive Medicine Classroom discussion topic on types of Epidemiological study designs available.
sole reference is Park text book 20th edition
Periodontal disease is a widely prevalent disease worldwide which often gets unnoticed or it often ignored due to its slowly progressive nature. It is of concern since it can cause irrepairable damage to tooth supporting structures if not early diagnosed or treated.
Observational research designs are those in which the researcher/investigator merely observes and does not carry out any interventions/actions.
to change the result. The three most common types of observational studies are cross-sectional studies, case-control studies, and cohort (or longitudinal) studies.
In cross-sectional studies, exposure/risk factors and outcomes are determined at a single point in time. You can bid
information on disease prevalence and an overview of likely relationships that can be used to form a hypothesis. Control cases In
studies, participants are selected based on the presence/absence of an outcome and risk factors are identified during the study.
after enrollment of study participants.The relationship between exposure and outcome is reported as an odds ratio. This research; However,
carries a high risk of bias, which should be taken into account when designing the study. Cohort studies are prospective and include participants
were selected based on presence/absence of exposure and results were obtained at the end of the study. This research can deliver The incidence/impact of the disease and the relationship between exposure and outcome are presented as relative risks. They are useful
establish causality.A problem that arises in these studies could be the high fluctuation and dropout of study participants.
Descriptive studies generally describe the magnitude of a problem and characteristics of the population/individuals.
The various types of such studies include
case reports
case series or surveys.
A case report generally describes a patient presenting with an unusual disease, or simultaneous occurrence of more than one condition, or uncommon clinical features in a known disease.
A case series is a collection of similar cases. Such studies, other than providing some advancement to knowledge of a disease, are of limited value. Another method often used in epidemiological health care research is conducting surveys.
Surveys are done during a defined time-period and information on several variables of interest is collected from the target population. They provide estimates of prevalence of the various variables of interest, and their distribution. Such studies could also provide insight into individual opinions and practices. Advantages include ease of conduct and cost efficiency. The disadvantages include low response rates and a variety of biases.
An analytical study tests a hypothesis to determine an association between two or more variables, like causation, risk, or effect. Such studies have two or more study groups for comparison.
The primary focus of this article will be the three most common types of analytical observational studies –
cross-sectional,
case control (also known as retrospective) and
cohort (or longitudinal, also known as prospective) studies.
It may be pertinent to note that the primary objective of most clinical studies is to determine one of the following - burden of disease (prevalence
Comparative Observational Studies Major types of these designs are cross-sectional studies, case-control studies, and cohort studies (both retrospective and prospective)
Epidemiology is the study and analysis of the patterns, causes, and effects of health, disease & production conditions in defined populations, in terms of space and temporality.
Epidemiology designs for clinical trials - PubricaPubrica
1. Clinical trial study design
2. Cohort Study design
3. Case-Control Studies
4. Cross-Sectional Studies
5. Ecological Studies
6. Randomized Clinical Trials
Continue Reading: https://bit.ly/3tDt6rH
Reference: https://pubrica.com/services/research-services/experimental-design/
Why Pubrica:
When you order our services, We promise you the following – Plagiarism free | always on Time | 24*7 customer support | Written to international Standard | Unlimited Revisions support | Medical writing Expert | Publication Support | Biostatistical experts | High-quality Subject Matter Experts.
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Periodontal disease is a widely prevalent disease worldwide which often gets unnoticed or it often ignored due to its slowly progressive nature. It is of concern since it can cause irrepairable damage to tooth supporting structures if not early diagnosed or treated.
Observational research designs are those in which the researcher/investigator merely observes and does not carry out any interventions/actions.
to change the result. The three most common types of observational studies are cross-sectional studies, case-control studies, and cohort (or longitudinal) studies.
In cross-sectional studies, exposure/risk factors and outcomes are determined at a single point in time. You can bid
information on disease prevalence and an overview of likely relationships that can be used to form a hypothesis. Control cases In
studies, participants are selected based on the presence/absence of an outcome and risk factors are identified during the study.
after enrollment of study participants.The relationship between exposure and outcome is reported as an odds ratio. This research; However,
carries a high risk of bias, which should be taken into account when designing the study. Cohort studies are prospective and include participants
were selected based on presence/absence of exposure and results were obtained at the end of the study. This research can deliver The incidence/impact of the disease and the relationship between exposure and outcome are presented as relative risks. They are useful
establish causality.A problem that arises in these studies could be the high fluctuation and dropout of study participants.
Descriptive studies generally describe the magnitude of a problem and characteristics of the population/individuals.
The various types of such studies include
case reports
case series or surveys.
A case report generally describes a patient presenting with an unusual disease, or simultaneous occurrence of more than one condition, or uncommon clinical features in a known disease.
A case series is a collection of similar cases. Such studies, other than providing some advancement to knowledge of a disease, are of limited value. Another method often used in epidemiological health care research is conducting surveys.
Surveys are done during a defined time-period and information on several variables of interest is collected from the target population. They provide estimates of prevalence of the various variables of interest, and their distribution. Such studies could also provide insight into individual opinions and practices. Advantages include ease of conduct and cost efficiency. The disadvantages include low response rates and a variety of biases.
An analytical study tests a hypothesis to determine an association between two or more variables, like causation, risk, or effect. Such studies have two or more study groups for comparison.
The primary focus of this article will be the three most common types of analytical observational studies –
cross-sectional,
case control (also known as retrospective) and
cohort (or longitudinal, also known as prospective) studies.
It may be pertinent to note that the primary objective of most clinical studies is to determine one of the following - burden of disease (prevalence
Comparative Observational Studies Major types of these designs are cross-sectional studies, case-control studies, and cohort studies (both retrospective and prospective)
Epidemiology is the study and analysis of the patterns, causes, and effects of health, disease & production conditions in defined populations, in terms of space and temporality.
Epidemiology designs for clinical trials - PubricaPubrica
1. Clinical trial study design
2. Cohort Study design
3. Case-Control Studies
4. Cross-Sectional Studies
5. Ecological Studies
6. Randomized Clinical Trials
Continue Reading: https://bit.ly/3tDt6rH
Reference: https://pubrica.com/services/research-services/experimental-design/
Why Pubrica:
When you order our services, We promise you the following – Plagiarism free | always on Time | 24*7 customer support | Written to international Standard | Unlimited Revisions support | Medical writing Expert | Publication Support | Biostatistical experts | High-quality Subject Matter Experts.
Contact us:
Web: https://pubrica.com/
Blog: https://pubrica.com/academy/
Email: sales@pubrica.com
WhatsApp : +91 9884350006
United Kingdom: +44- 74248 10299
Opendatabay - Open Data Marketplace.pptxOpendatabay
Opendatabay.com unlocks the power of data for everyone. Open Data Marketplace fosters a collaborative hub for data enthusiasts to explore, share, and contribute to a vast collection of datasets.
First ever open hub for data enthusiasts to collaborate and innovate. A platform to explore, share, and contribute to a vast collection of datasets. Through robust quality control and innovative technologies like blockchain verification, opendatabay ensures the authenticity and reliability of datasets, empowering users to make data-driven decisions with confidence. Leverage cutting-edge AI technologies to enhance the data exploration, analysis, and discovery experience.
From intelligent search and recommendations to automated data productisation and quotation, Opendatabay AI-driven features streamline the data workflow. Finding the data you need shouldn't be a complex. Opendatabay simplifies the data acquisition process with an intuitive interface and robust search tools. Effortlessly explore, discover, and access the data you need, allowing you to focus on extracting valuable insights. Opendatabay breaks new ground with a dedicated, AI-generated, synthetic datasets.
Leverage these privacy-preserving datasets for training and testing AI models without compromising sensitive information. Opendatabay prioritizes transparency by providing detailed metadata, provenance information, and usage guidelines for each dataset, ensuring users have a comprehensive understanding of the data they're working with. By leveraging a powerful combination of distributed ledger technology and rigorous third-party audits Opendatabay ensures the authenticity and reliability of every dataset. Security is at the core of Opendatabay. Marketplace implements stringent security measures, including encryption, access controls, and regular vulnerability assessments, to safeguard your data and protect your privacy.
Chatty Kathy - UNC Bootcamp Final Project Presentation - Final Version - 5.23...John Andrews
SlideShare Description for "Chatty Kathy - UNC Bootcamp Final Project Presentation"
Title: Chatty Kathy: Enhancing Physical Activity Among Older Adults
Description:
Discover how Chatty Kathy, an innovative project developed at the UNC Bootcamp, aims to tackle the challenge of low physical activity among older adults. Our AI-driven solution uses peer interaction to boost and sustain exercise levels, significantly improving health outcomes. This presentation covers our problem statement, the rationale behind Chatty Kathy, synthetic data and persona creation, model performance metrics, a visual demonstration of the project, and potential future developments. Join us for an insightful Q&A session to explore the potential of this groundbreaking project.
Project Team: Jay Requarth, Jana Avery, John Andrews, Dr. Dick Davis II, Nee Buntoum, Nam Yeongjin & Mat Nicholas
Levelwise PageRank with Loop-Based Dead End Handling Strategy : SHORT REPORT ...Subhajit Sahu
Abstract — Levelwise PageRank is an alternative method of PageRank computation which decomposes the input graph into a directed acyclic block-graph of strongly connected components, and processes them in topological order, one level at a time. This enables calculation for ranks in a distributed fashion without per-iteration communication, unlike the standard method where all vertices are processed in each iteration. It however comes with a precondition of the absence of dead ends in the input graph. Here, the native non-distributed performance of Levelwise PageRank was compared against Monolithic PageRank on a CPU as well as a GPU. To ensure a fair comparison, Monolithic PageRank was also performed on a graph where vertices were split by components. Results indicate that Levelwise PageRank is about as fast as Monolithic PageRank on the CPU, but quite a bit slower on the GPU. Slowdown on the GPU is likely caused by a large submission of small workloads, and expected to be non-issue when the computation is performed on massive graphs.
Best best suvichar in gujarati english meaning of this sentence as Silk road ...
Quantitative Methods.pptx
1. Dr. Khem R. Sharma, Assistant Professor
School of Public Health & Community Medicine, BPKIHS
2. To describe the burden of disease or prevalence of risk
factors, health behaviors, or other characteristics of a
population that influences the risk of disease
To determine the causes or risk factors for illness
To determine the relative effectiveness of interventions
2
3. Medical Research methods include scientific ways to
distinguish facts from fiction in broadly two categories:
1) Quantitative research methods: emphasize objective
measurements (numerical data) and analysis of poll,
questionnaire data or manipulating pre-existing
statistical data using different computational
techniques.
2) Qualitative research methods: focused more on
discovering underlying meanings and patterns of
relationships in a manner, that does not involve
mathematical models. Example: Focus Group
Discussion 3
4. Quantitative research is a systematic investigation of
assembling quantifiable data and performing statistical,
mathematical or computational techniques to present it.
The goal in conducting quantitative research study is to
determine the relationship of one entity [independent variable]
with another [dependent or outcome variable] within a
population.
Quantitative research designs are either descriptive [subjects
usually measured once & establishes only associations between
variables] or experimental [subjects measured before and after
a treatment & establishes causality].
4
5. Structured tools: Questionnaires are used to gather quantitative
data which helps in collecting in-depth and accurate information
from the survey respondents.
Sample size: Quantitative research is conducted based on
significant sample size that represents the target population, with
the use of appropriate sampling methods to meet the research
objectives
Prior studies and preparation: Adequate groundwork needs to be
done before starting the study as all aspects of the study needs to be
carefully designed before data collection ensues.
5
6. Quantitative data: in the form of numbers and statistics
represented by tables, charts, graphs etc. makes it easy to
understand the information
Generalization of results: Results of the research can be generalized
to a subgroup or even the entire population to take appropriate
actions for improvement.
The study can usually be replicated or repeated, given its high
reliability.
6
7. Quantitative methods have an objective approach to studying
research problems as a consequence, the results of quantitative
research may be statistically significant but may be humanly
insignificant.( Biologically not plausible)
Though more efficient and able to test hypotheses, it may miss
contextual detail;
Uses a static and rigid approach and so employs an inflexible
process of discovery;
Results provide less detail on behavior, attitudes, and
motivation; 9
8. I. Observational Studies
a) Descriptive (case study, case series, cross-sectional)
b) Analytical (cross-sectional, case-control, cohort ,
ecological studies)
II. Experimental Studies
a) Randomized Control Trial (RCT/ Clinical Trials)
b) Field Trials (Healthy people as units)
c) Community trials (Communities as units of study)
10
9. Observational studies allows nature to take its own
course; the investigator keeps measuring, but does not
intervene.
Descriptive studies are limited to description of the
problem that exists in that population
Analytical studies go one step further and analyses the
relation between the outcome variable and various factors
implicated in its occurrence.
Experimental/Intervention studies involve active
interventions to change the progression of a disease/event.
11
10. The first phase of an epidemiological investigation concerned
with observing the distribution of disease or health-related
characteristics in human populations & identifying the factor
with which the disease seems to be associated.
Such studies basically ask the questions.
a) When is the disease occurring ? - time distribution
b) Where is it occurring ? - place distribution
c) Who is getting the disease? - person
distribution
12
11. Analytical Studies
interest is the individual within
the population
to test hypothesis
inference is not to individuals.
but to the population from
which they are selected.
Answer why and how
Descriptive Studies
• look at entire populations
• to formulate hypothesis
• gives person, time & place
status of Health Problems
• Answer what, who, where,
and when
13
12. Simplest form of an observational study
Based on a single examination of a cross-section of
population at one point in time - the results of which can be
projected on the whole population (Photograph)
Usually Descriptive-Analytical when two groups are
compared
Provides very little information about the natural history of
disease or about the rate of occurrence of new cases
(incidence).
14
13. Common first approach to test causal hypothesis
Three distinct features:
a) Both exposure & outcome have occurred before the start of
study
b) Study proceeds backwards from effect(outcome) to cause
(exposure)
c) Uses a control/ comparision group to support or refute an
inference
To study rare diseases
To study multiple exposures that may be related to a single
outcome
15
15. 1) Selection of cases and controls: suitable controls may present
difficulties
Sources: Case(hospital/gen population)
Controls- (hospital/relatives/neighbor hood/gen popn)
2) Matching to ensure comparability between cases and control but
controls should free from the disease under study.
Process by which controls are selected such that they are similar to
cases with regard to certain pertinent selected variables (e.g., age,
gender etc) which are known to influence the outcome of disease and
which if not adequately matched for comparability, could confound
the results (eg: Alcohol in esophageal cancer VS cig).
17
16. 3) Measurement of exposure: Definitions and criteria of exposure
should be the same and information about exposure should be
obtained in precisely the same manner for both cases and
controls
obtained by interviews/questionnaires or studying past hospital,
employment records etc. of cases
4) Analysis: to find out-
a) Exposure rates among cases & controls to the suspected factor +
b) Estimation of disease risk associated with exposure (Odds
Ratio)
18
17. Measure of the strength of the association between risk factor and outcome.
cross product of the 2 X 2 table
OR= ad/bc
Odds ratio is based on three assumptions:
1) the disease being investigated must be relatively rare
2) the cases must be representative of those with the disease, &
3) The controls must be representative of those without the disease.
If a race horse runs 100 races and wins 25 times and loses the rest, the
probability of winning is 25/100 = 0.25 or 25%, but the odds of the horse
winning are 25/75 = 0.333 or 1 win to 3 loses.
19
18. What is a cohort?
-Well-defined group of people who share a common
characteristic or experience within a defined time period
(e.g., age, occupation, exposure to a drug or vaccine,
pregnancy etc).
Example: Those born in 1990 form the birth cohort of
1990
What are other examples of cohorts?
20
19. Longitudinal study, follow-up study
Participants classified according to exposure status and
followed-up over time to ascertain outcome
Can be used to find multiple outcomes from a single exposure
Appropriate for rare exposures or defined cohorts
Ensures temporality (exposure occurs before observed
outcome)
21
21. COHORT STUDY
The distinguishing features of cohort studies are :
1) the cohorts are identified prior to the appearance of the
disease under investigation
2) the defined study groups are observed over a period of
time to determine the frequency of disease among them
3) the study proceeds forward from cause to effect.
23
22. 1) when there is good evidence of an association between exposure
and disease as derived from clinical observations and supported
by descriptive and case control studies
2) when exposure is rare but the incidence of disease high among
exposed. (eg: hirosima nuclear disaster/Bhopal gas)
3) To learn about multiple outcomes due to a single exposure (eg:
Health effects of a nuclear power plant accident)
4) when attrition of study population can be minimized e.g., follow-
up is easy, cohort is stable, cooperative and easily accessible
5) when ample funds are available.
24
23. Three types of cohort studies have been distinguished on the basis of the
time of occurrence of disease in relation to the time at which the
investigation is initiated and continued :
1) Prospective cohort studies: Eg - Doll & Hill, Framingham Heart Study
2) Retrospective cohort studies: Eg: study of lung cancer in uranium
miners
3) Combination of retrospective and prospective cohort studies:
The cohort is identified from past records, assessed to date for the
outcome and the same cohort is followed up prospectively into future for
further assessment of outcome.
25
24. It is a direct measure (or index) of the "strength" of the
association between suspected cause and effect.
A RR of one indicates no association while RR of 2 indicates
that the incidence rate of disease is 2 times higher in the
exposed group as compared with the unexposed
RR = Incidence of disease (or death) among exposed
Incidence of disease (or death) among non-exposed
26
25. The difference in incidence rates of disease (or death)
between an exposed group and non-exposed group expressed
as a percentage.
Attributable risk indicates to what extent the disease under
study can be attributed to the exposure
Population Attributable Risk (PAR) provides an estimate of
the amount by which the disease could be reduced in that
population if the suspected factor was eliminated or modified.
27
26. Experimental research studies compare the effectiveness
of medical treatments, management & prevention
strategies, and other medical or public health
interventions.
Design is very similar to that of a prospective cohort
study- intervention is present.
Investigator assigns the exposure status in clinical trials,
while subjects' genetics, behaviors, and life circumstances
determine their exposures in a cohort study
28