The document provides an introduction to common measures and statistics used in epidemiological literature. It defines measures of frequency such as risk, rate, and prevalence which characterize the occurrence of health outcomes in a population. Risk ratios and odds ratios are presented as measures of the strength of association between an exposure and outcome. The null value in epidemiological studies is 1.0 for risk ratios, rate ratios, and odds ratios, representing no association. Confidence intervals are discussed as a measure of precision of an estimate. Crude and adjusted values are also explained as ways to account for confounding factors.
this presentation takes you through the concept of association observed between variables in a study and how could it become a causative association in step-wise manner.Exemplify using Bradford hill criteria. slides after references are extra slides not covered in the presentation.
A principal aim of epidemiology is to assess the cause of disease. However, since most epidemiological studies are by nature observational rather than experimental, a number of possible explanations for an observed association need to be considered before we can infer a cause-effect relationship exists.
this presentation takes you through the concept of association observed between variables in a study and how could it become a causative association in step-wise manner.Exemplify using Bradford hill criteria. slides after references are extra slides not covered in the presentation.
A principal aim of epidemiology is to assess the cause of disease. However, since most epidemiological studies are by nature observational rather than experimental, a number of possible explanations for an observed association need to be considered before we can infer a cause-effect relationship exists.
Bias, confounding and causality in p'coepidemiological researchsamthamby79
A brief description of three issues (Bias, Confounding and Causality) commonly encountered while performing pharmacoepidemiological research. A big THANK YOU to Mr. Strom and Mr. Kimmel.
At the end of this session, the students shall be able to, Define Cause
Define Association
Define Correlation
Types of association
Additional criteria for judging causality
Differentiate between association and causation
Standardization of rates by Dr. Basil TumainiBasil Tumaini
Standardization of rates by Dr. Basil Tumaini, presented during the residency at Muhimbili University of Health and Allied Sciences, Epidemiology class
You have just finished a health education in-service to the communit.docxbriancrawford30935
You have just finished a health education in-service to the community on the hazards of smoking. A representative of the tobacco industry is present at your in-service and makes the following comment regarding your presentation: "You gave a nice presentation. However, I disagree with you that smoking can cause lung cancer. There is still not enough evidence to indicate that smoking can cause cancer."
Your task is as follows:
1. Respond to his statement and indicate why there is a cause-effect relationship between smoking and lung cancer using the
five criteria for causality
.
2. What is your interpretation of the evidence on how smoking affects lung cancer?
READ: FIVE CRITERIA FOR CAUSALITY
Assignment Expectations, in order to earn full credit:
Please write your paper in your own words. That is the only way I can evaluate your level
Analytic epidemiology is defined as the study of the determinants of disease or reasons for relatively high or low frequency in specific groups. Analytic epidemiology answers questions regarding why the rate is high or low in a particular group. Observations of differences lead to formation of hypotheses.
Analytic Studies
There are basically two types of studies: experimental and observational. In an experimental study, the exposure has not occurred yet. The investigator controls the exposure in the study groups and studies the impact. For example, he may immunize one group with an experimental vaccine that has been developed for a disease and compare the frequency with which the disease develops to the control group (which had no modification). In an observational study, the exposure has already occurred. The exposures and outcomes are observed and analyzed, not created experimentally. Observational studies are often more practical and continue to provide the major contribution to our understanding of diseases. There are two main types of observational studies: cohort (prospective) and case-control (retrospective) studies.
In a cohort study, a group of people who share a common experience within a defined time period (cohort) are categorized based upon their exposure status. For example, individuals at a work place where an asbestos exposure occurred would be considered a cohort. Another example would be individuals attending a wedding where a foodborne illness occurred. Cohort studies have well-defined populations. Often, cohort studies involve following a cohort over time in order to determine the rate at which a disease develops in relation to the exposure.
In a cohort study, relative risk is used to determine whether an association exists between an exposure and a disease. Relative risk is defined as ratio of the incidence rate among exposed individuals to the incidence rate among unexposed individuals.
To calculate the relative risk, you would use the following formula:
(a/a+b) / (c/c+d)
where:
a = the number of individuals with a disease who were exposed.
b = the number of individ.
Analytic StudiesThere are basically two types of studies experi.docxrossskuddershamus
Analytic Studies
There are basically two types of studies: experimental and observational. In an experimental study, the exposure has not occurred yet. The investigator controls the exposure in the study groups and studies the impact. For example, he may immunize one group with an experimental vaccine that has been developed for a disease and compare the frequency with which the disease develops to the control group (which had no modification). In an observational study, the exposure has already occurred. The exposures and outcomes are observed and analyzed, not created experimentally. Observational studies are often more practical and continue to provide the major contribution to our understanding of diseases. There are two main types of observational studies: cohort (prospective) and case-control (retrospective) studies.
In a cohort study, a group of people who share a common experience within a defined time period (cohort) are categorized based upon their exposure status. For example, individuals at a work place where an asbestos exposure occurred would be considered a cohort. Another example would be individuals attending a wedding where a foodborne illness occurred. Cohort studies have well-defined populations. Often, cohort studies involve following a cohort over time in order to determine the rate at which a disease develops in relation to the exposure.
In a cohort study, relative risk is used to determine whether an association exists between an exposure and a disease. Relative risk is defined as ratio of the incidence rate among exposed individuals to the incidence rate among unexposed individuals.
To calculate the relative risk, you would use the following formula: (a/a+b) / (c/c+d) where:
a = the number of individuals with a disease who were exposed.
b = the number of individuals without a disease who were exposed.
c = the number of individuals with a disease who were NOT exposed.
d = the number of individuals without a disease who were NOT exposed.
In a case-control study, the sample is based upon illness status, rather than exposure status. The researcher identifies a group of people who meet the case definition and a group of people who do not have the illness (controls). The objective is to determine if the two groups differ in the rate of exposure to a specific factor or factors.
In contrast to a cohort study, the total number of people exposed in a case-control study is unknown. Therefore, relative risk cannot be used. Instead, an odds ratio or risk ratio is used. An odds ratio measures the odds that an exposed individual will develop a disease in comparison to an unexposed individual. Please click the button below to learn how to calculate an odds ratio.
To calculate an odds ratio, you would use the following formula: ad/bc
where:
a = the number of individuals with a disease who were exposed.
b = the number of individuals without a disease who were exposed.
c = the number of individu.
Bias, confounding and causality in p'coepidemiological researchsamthamby79
A brief description of three issues (Bias, Confounding and Causality) commonly encountered while performing pharmacoepidemiological research. A big THANK YOU to Mr. Strom and Mr. Kimmel.
At the end of this session, the students shall be able to, Define Cause
Define Association
Define Correlation
Types of association
Additional criteria for judging causality
Differentiate between association and causation
Standardization of rates by Dr. Basil TumainiBasil Tumaini
Standardization of rates by Dr. Basil Tumaini, presented during the residency at Muhimbili University of Health and Allied Sciences, Epidemiology class
You have just finished a health education in-service to the communit.docxbriancrawford30935
You have just finished a health education in-service to the community on the hazards of smoking. A representative of the tobacco industry is present at your in-service and makes the following comment regarding your presentation: "You gave a nice presentation. However, I disagree with you that smoking can cause lung cancer. There is still not enough evidence to indicate that smoking can cause cancer."
Your task is as follows:
1. Respond to his statement and indicate why there is a cause-effect relationship between smoking and lung cancer using the
five criteria for causality
.
2. What is your interpretation of the evidence on how smoking affects lung cancer?
READ: FIVE CRITERIA FOR CAUSALITY
Assignment Expectations, in order to earn full credit:
Please write your paper in your own words. That is the only way I can evaluate your level
Analytic epidemiology is defined as the study of the determinants of disease or reasons for relatively high or low frequency in specific groups. Analytic epidemiology answers questions regarding why the rate is high or low in a particular group. Observations of differences lead to formation of hypotheses.
Analytic Studies
There are basically two types of studies: experimental and observational. In an experimental study, the exposure has not occurred yet. The investigator controls the exposure in the study groups and studies the impact. For example, he may immunize one group with an experimental vaccine that has been developed for a disease and compare the frequency with which the disease develops to the control group (which had no modification). In an observational study, the exposure has already occurred. The exposures and outcomes are observed and analyzed, not created experimentally. Observational studies are often more practical and continue to provide the major contribution to our understanding of diseases. There are two main types of observational studies: cohort (prospective) and case-control (retrospective) studies.
In a cohort study, a group of people who share a common experience within a defined time period (cohort) are categorized based upon their exposure status. For example, individuals at a work place where an asbestos exposure occurred would be considered a cohort. Another example would be individuals attending a wedding where a foodborne illness occurred. Cohort studies have well-defined populations. Often, cohort studies involve following a cohort over time in order to determine the rate at which a disease develops in relation to the exposure.
In a cohort study, relative risk is used to determine whether an association exists between an exposure and a disease. Relative risk is defined as ratio of the incidence rate among exposed individuals to the incidence rate among unexposed individuals.
To calculate the relative risk, you would use the following formula:
(a/a+b) / (c/c+d)
where:
a = the number of individuals with a disease who were exposed.
b = the number of individ.
Analytic StudiesThere are basically two types of studies experi.docxrossskuddershamus
Analytic Studies
There are basically two types of studies: experimental and observational. In an experimental study, the exposure has not occurred yet. The investigator controls the exposure in the study groups and studies the impact. For example, he may immunize one group with an experimental vaccine that has been developed for a disease and compare the frequency with which the disease develops to the control group (which had no modification). In an observational study, the exposure has already occurred. The exposures and outcomes are observed and analyzed, not created experimentally. Observational studies are often more practical and continue to provide the major contribution to our understanding of diseases. There are two main types of observational studies: cohort (prospective) and case-control (retrospective) studies.
In a cohort study, a group of people who share a common experience within a defined time period (cohort) are categorized based upon their exposure status. For example, individuals at a work place where an asbestos exposure occurred would be considered a cohort. Another example would be individuals attending a wedding where a foodborne illness occurred. Cohort studies have well-defined populations. Often, cohort studies involve following a cohort over time in order to determine the rate at which a disease develops in relation to the exposure.
In a cohort study, relative risk is used to determine whether an association exists between an exposure and a disease. Relative risk is defined as ratio of the incidence rate among exposed individuals to the incidence rate among unexposed individuals.
To calculate the relative risk, you would use the following formula: (a/a+b) / (c/c+d) where:
a = the number of individuals with a disease who were exposed.
b = the number of individuals without a disease who were exposed.
c = the number of individuals with a disease who were NOT exposed.
d = the number of individuals without a disease who were NOT exposed.
In a case-control study, the sample is based upon illness status, rather than exposure status. The researcher identifies a group of people who meet the case definition and a group of people who do not have the illness (controls). The objective is to determine if the two groups differ in the rate of exposure to a specific factor or factors.
In contrast to a cohort study, the total number of people exposed in a case-control study is unknown. Therefore, relative risk cannot be used. Instead, an odds ratio or risk ratio is used. An odds ratio measures the odds that an exposed individual will develop a disease in comparison to an unexposed individual. Please click the button below to learn how to calculate an odds ratio.
To calculate an odds ratio, you would use the following formula: ad/bc
where:
a = the number of individuals with a disease who were exposed.
b = the number of individuals without a disease who were exposed.
c = the number of individu.
Consider the following hypothet-ical scenario and results .docxdonnajames55
C
onsider the following hypothet-
ical scenario and results that are
formatted in evidence-based
practice (EBP) language such as those
that you might see in the Cochrane
Collaboration,1 a primary resource for
evidence-based systematic reviews.
Scenario: How effective is a daily
dose of 500 mg of vitamin C in
the prevention of ulcers on the heels of
bedridden elderly clients? Results: With
an NNT of 5, vitamin C is effective (OR,
0.10; 95% CI, 0.05-0.20).
If there are some abbreviations
or values in this situation that are un-
familiar to you, you will find explana-
tions and examples in this article that
will help you in reading, interpreting,
and understanding them as you use
evidence-based literature for your best
practices. Nurses always rise to the
occasion to learn the latest research
information that may improve patient
care and outcomes.
An obstacle to involvement in EBP
is lack of skill in understanding the
‘‘bottom line’’ of systematic reviews
and accompanying risk-related num-
bers.
2-4
Content and research experts
conduct systematic reviews using strict
criteria for inclusion of primary re-
search studies and statistical analysis.
5
The Cochrane Collaboration is a major
resource for more than 1,000 system-
atic reviews of randomized clinical
trials for the effects of healthcare inter-
ventions created through collaboration
of more than 50 worldwide review and
methods teams.6
The systematic review teams basi-
cally seek the response to 1 question:
how many people have a bad outcome
in the experimental group compared
with the control group? Bad outcomes
refer to the undesirable outcomes in a
study, such as development of a heel
ulcer. Noteworthy in EBP statistics is
the simplicity of using a head count
rather than group averages. Even when
individual study results are not statisti-
cally significant, if the experimental
group has fewer bad outcomes than the
control group, the nurse or other pro-
vider might want to apply the results
anyway. Seven terms and their abbre-
viations and formulas are common in
the reported results,7,8 as summarized
in Table 1. In this article, hypothetical
examples and their derivations de-
scribe these 7 terms. At the end, you
can derive these values for a clinical
scenario toward a better understanding
when teaching these terms to others.
Absolute Risk Reduction
Absolute risk reduction (ARR) is the
absolute arithmetic difference (abso-
lute means that one ignores plus and
minus signs) in percentages of bad
outcomes between the experimental
and control groups. Absolute risk reduc-
tion means that more people in the
control group than in the experimen-
tal group develop a bad outcome. To
calculate the ARR, you need to know
just 2 things: the experimental event
rate (EER), or the percentage of the
bad outcome in the experimental group;
and the control group event rate (CER),
or the percentage of the bad outcome in
the control group. Let us look at an ex-
ample: 13% of patients with diabetes
receiv.
Study of the distribution and determinants of
health-related states or events in specified populations and the application of this study to control health problems.
John M. Last, Dictionary of Epidemiology
P-values the gold measure of statistical validity are not as reliable as many...David Pratap
This is an article that appeared in the NATURE as News Feature dated 12-February-2014. This article was presented in the journal club at Oman Medical College , Bowshar Campus on December, 17, 2015. This article was presented by Pratap David , Biostatistics Lecturer.
Excelsior College PBH 321 Page 1 BIAS IN EPIDE.docxgitagrimston
Excelsior College PBH 321
Page 1
BIAS IN EPIDE MIOLO GY
THE MEANING AND CONTEXT OF BIAS
We briefly touched upon bias earlier in the course. The word bias probably has an intuitive meaning to you,
and recall the definition from Module 3:
“Deviation of results or inferences from the truth, or processes leading to such deviation. Any trend in the
collection, analysis, interpretation, publication, or review of data that can lead to conclusions that are
systematically different from the truth.” (J.M. Last, A Dictionary of Epidemiology, 4th ed.)
Bias is a systematic error that results in an incorrect (invalid) estimate of the measure of association. Bias can
therefore create the appearance of an association when there really is none (bias away from the null), or mask
an association when there really is one (bias towards the null). Bias can arise in all study types: experimental,
cohort, and case-control designs. It is primarily introduced by the investigator or study participants in the
design and conduction of a study, and once it occurs, cannot be removed – but it can be evaluated during the
analysis phase of a study. Bias is a direct threat to the validity of any epidemiologic study, and influences
whether we can believe the observed association is a true association.
DIRECTION OF BIAS
We can describe the impact of bias on the measure of association in a few different ways. Remember, the null
value is 1.0; the value that means there is no observed association between exposure and disease. If the true
association is protective (less than 1.0), bias towards the null will make it seem less protective as the measure
of association gets closer to the null value.
• Positive bias: the observed value is higher than the true value
• Negative bias: the observed value is lower than the true value
• Bias towards the null: the observed value is closer to 1.0 than the true value.
• Bias away from the null: the observed value is farther away from 1.0 than the true value.
Bias towards null
Bias away from null
Bias away from null
Bias towards null
Protective effects Harmful effects
1.0
(no association)
Bias towards null
Bias away from null
Bias away from null
Bias towards null
Protective effects Harmful effects
1.0
(no association)
Excelsior College PBH 321
Page 2
TYPES OF BIAS
Two main types of bias are selection and information (observation) bias. You had an introduction to these
biases in Module 4.
1. Selection Bias
Selection bias is error that occurs if selection of subjects into a study is related to both exposure and disease.
As a result, the measure of association differs from what would have been obtained if we could examine the
entire population targeted for study. Selection bias is most likely to occur in case-control or retrospective
cohort studies because exposure and outcome have occurred at time of study selection, and may influence
the willing ...
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
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Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
Common measures and statistics in epidemiological literature
1. Common Measures and Statistics
in Epidemiological Literature
Dr. Mohammed Jawad
2. Introduction
• For the non-epidemiologist or non-
statistician, understanding the statistical
nomenclature presented in journal articles
can sometimes be challenging, particularly
since multiple terms are often used
interchangeably, and still others are
presented without definition.
• This lecture will provide a basic introduction
to the terminology commonly found in
epidemiological literature.
4. Measures of
frequency
• Measures of frequency characterize the
occurrence of health outcomes, disease, or
death in a population.
• These measures are descriptive in nature
and indicate how likely one is to develop a
health outcome in a specified population.
• The three most common measures of health
outcome or frequency are risk, rate, and
prevalence.
5. Risk
• Risk, also known as incidence, cumulative
incidence, incidence proportion, or attack
rate (although not really a rate at all) is a
measure of the probability of an unaffected
individual developing a specified health
outcome over a given period of time. For a
given period of time (i.e.: 1 month, 5 years,
lifetime):
• A 5-year risk of 0.10 indicates that an
individual at risk has a 10% chance of
developing the given health outcome over a
5-year period of time.
6. Risk ratio and rate ratio
Risk ratios or rate ratios are commonly
found in cohort studies and are
defined as: the ratio of the risk in the
exposed group to the risk in the
unexposed group or the ratio of the
rate in the exposed group to the rate
in the unexposed group
7. Risk ratio
and rate
ratio
• Risk ratios and rate ratios are measures of the strength of the association
between the exposure and the outcome.
• How is a risk ratio or rate ratio interpreted?
• A risk ratio of 1.0 indicates there is no difference in risk between the
exposed and unexposed group.
• A risk ratio greater than 1.0 indicates a positive association, or
increased risk for developing the health outcome in the exposed
group.
• A risk ratio of 1.5 indicates that the exposed group has 1.5 times the
risk of having the outcome as compared to the unexposed group.
• Rate ratios can be interpreted the same way but apply to rates
rather than risks.
8. Risk ratio
and rate
ratio
• A risk ratio or rate ratio of less than 1.0
indicates a negative association between the
exposure and outcome in the exposed group
compared to the unexposed group.
• In this case, the exposure provides a
protective effect.
• For example, a rate ratio of 0.80 where the
exposed group received a vaccination for
Human Papillomavirus (HPV) indicates that
the exposed group (those who received the
vaccine) had 0.80 times the rate of HPV
compared to those who were unexposed
(did not receive the vaccine).
9. Risk ratio
and rate
ratio
• One of the benefits the measure risk
difference has over the risk ratio is that it
provides the absolute difference in risk,
information that is not provided by the ratio
of the two.
• A risk ratio of 2.0 can imply both a doubling
of a very small or large risk, and one cannot
determine which is the case unless the
individual risks are presented.
11. Odds ratio
• The odds ratio is used in place of the risk ratio
or rate ratio in case-control studies.
• In this type of study, the underlying population
at risk for developing the health outcome or
disease cannot be determined because
individuals are selected as either diseased or
non-diseased or as having the health outcome
or not having the health outcome.
• An odds ratio may approximate the risk ratio or
rate ratio in instances where the health
outcome prevalence is low (less that 10%) and
specific sampling techniques are utilized,
otherwise there is a tendency for the OR to
overestimate the risk ratio or rate ratio.
12. Odds ratio
• The odds ratio is interpreted in the same
manner as the risk ratio or rate ratio with an
OR of 1.0 indicating no association, an OR
greater than 1.0 indicating a positive
association, and an OR less than 1.0
indicating a negative, or protective
association.
13. The null
value
• The null value is a number corresponding to
no effect, that is, no association between
exposure and the health outcome. In
epidemiology, the null value for a risk ratio
or rate ratio is 1.0, and it is also 1.0 for odds
ratios and prevalence ratios (terms you will
come across). A risk ratio, rate ratio, odds
ratio or prevalence ratio of 1.0 is obtained
when, for a risk ratio for example, the risk of
disease among the exposed is equal to the
risk of disease among the unexposed.
14. The null
value
• Statistical testing focuses on the null
hypothesis, which is a statement predicting
that there will be no association between
exposure and the health outcome (or
between the assumed cause and its effect),
i.e. that the risk ratio, rate ratio or odds ratio
will equal 1.0.
• If the data obtained from a study provide
evidence against the null hypothesis, then
this hypothesis can be rejected, and an
alternative hypothesis becomes more
probable.
15. The null
value
• For example, a null hypothesis would say that there
is no association between children having cigarette
smoking mothers and the incidence of asthma in
those children.
• If a study showed that there was a greater incidence
of asthma among such children (compared with
children of nonsmoking mothers), and that the risk
ratio of asthma among children of smoking mothers
was 2.5 with a 95% confidence interval of 1.7 to 4.0,
we would reject the null hypothesis.
• The alternative hypothesis could be expressed in
two ways: 1) children of smoking mothers will have
either a higher or lower incidence of asthma than
other children, or 2) children of smoking mothers
will only have a higher incidence of asthma.
16. The null
value
• The first alternative hypothesis involves
what is called a "two-sided test" and is used
when we simply have no basis for predicting
in which direction from the null value
exposure is likely to be associated with the
health outcome, or, in other words, whether
exposure is likely to be beneficial or harmful.
• The second alternative hypothesis involves a
"one-sided test" and is used when we have a
reasonable basis to assume that exposure
will only be harmful (or if we were studying
a therapeutic agent, that it would only be
beneficial).
18. The p-value
• The "p" value is an expression of the
probability that the difference between the
observed value and the null value has
occurred by "chance", or more precisely, has
occurred simply because of sampling
variability.
• The smaller the "p" value, the less likely the
probability that sampling variability accounts
for the difference.
19. The p-
value
• Typically, a "p" value less than 0.05, is used
as the decision point, meaning that there is
less than a 5% probability that the difference
between the observed risk ratio, rate ratio,
or odds ratio and 1.0 is due to sampling
variability.
• If the "p" value is less than 0.05, the
observed risk ratio, rate ratio, or odds ratio is
often said to be "statistically significant."
However, the use of 0.05 as a cut-point is
arbitrary.
20. The p-
value
• The exclusive use of "p" values for
interpreting results of epidemiologic studies
has been strongly discouraged in the more
recent texts and literature because research
on human health is not conducted to reach a
decision point (a "go" or "no go" decision),
but rather to obtain evidence that there is
reason for concern about certain exposures
or lifestyle practices or other factors that
may adversely influence the health of the
public.
21. The p-
value
• Statistical tests of significance, (such as p-
values) were developed for industrial quality-
control purposes, in order to make a decision
whether the manufacture of some item is
achieving acceptable quality. We are not making
such decisions when we interpret the results of
research on human health.
• The lower bound of the 95% confidence interval
is also often utilized to decide whether a point
estimate is statistically significant, i.e. whether
the measure of effect (e.g. the ratio 2.5 with a
lower bound of 1.8) is statistically different than
the null value of 1.0.
23. Confidence
interval
• A confidence interval expresses the extent of
potential variation in a point estimate (the
mean value or risk ratio, rate ratio, or odds
ratio).
• This variation is attributable to the fact that
our point estimate of the mean or risk ratio,
rate ratio, or odds ratio is based on some
sample of the population rather than on the
entire population.
24. Confidence
interval
• For example, from a clinical trial, we might
conclude that a new treatment for high
blood pressure is 2.5 times as effective as
the standard treatment, with a 95%
confidence interval of 1.8 to 3.5.
• 2.5 is the point estimate we obtain from this
clinical trial. But not all subjects with high
blood pressure can be included in any study,
thus the estimate of effectiveness, 2.5, is
based on a particular sample of people with
high blood pressure.
25. Confidence
interval
• If we assume that we could draw other samples of
persons from the same underlying population as the
one from which subjects were obtained for this
study, we will obtain a set of point estimates, not all
of which would be exactly 2.5. Some samples would
be likely to show an effectiveness less than 2.5, and
some greater than 2.5.
• The 95% CI is an interval that would contain the
true, real (population) parameter value 95% of the
time if you repeated the experiment/study.
• So if we were to repeat the experiment/study, 95
out of 100 intervals would give an interval that
contains the true risk ratio, rate ratio or odds ratio
value.
26. Confidence
interval
• Remember, that you can only interpret the
CI in relation to talking about repeated
sampling.
• Thus we can also say that the new treatment
for high blood pressure is 2.5 times as
effective as the standard treatment, but this
measure could range from a low of 1.8 to a
high of 3.5.
27. Confidence
interval
• The confidence interval also provides
information about how precise an estimate
is.
• The tighter, or narrower, the confidence
interval, the more precise the estimate.
• Typically, larger sample sizes will provide a
more precise estimate.
• Estimates with wide confidence intervals
should be interpreted with caution.
29. Crude and
adjusted
values
• There are often two types of estimates
presented in research articles, crude and
adjusted values.
• Crude estimates refer to simple measures that
do not account for other factors that may be
driving the estimate.
• For instance, a crude death rate would simply
be the number of deaths in a calendar year
divided by the average population for that year.
• This may be an appropriate measure in certain
circumstances but could become problematic if
you want to compare two or more populations
that vary on specific factors known to contribute
to the death rate.
30. Crude and
adjusted
values
• For example, you may want to compare the
death rate for two populations, one of which is
located in a high air pollution area, to determine
if air pollution levels affect the death rate.
• The high air pollution population may have a
higher death rate, but you also determine that it
is a much older population. As older individuals
are more likely to die, age may be driving the
death rate rather than the pollution level.
31. Crude and
adjusted
values
• To account for the difference in age distribution
of the populations, one would want to calculate
an adjusted death rate that adjusts for the age
structure of the two groups.
• This would remove the effect of age from the
effect of air pollution on mortality.
32. Crude and
adjusted
values
• Adjusted estimates are a means of
controlling for confounders or accounting for
effect modifiers in analyses. Some factors
that are commonly adjusted for include
gender, race, socioeconomic status, smoking
status, and family history.
33. Practice
Questions
1. Based on the following table, calculate the
requested measures. Also provide the
definition for each measure in one
sentence.
a. The risk ratio comparing the exposed and
the unexposed study participants
b. The risk difference between the exposed
and the unexposed study participants
c. The prevalence of the disease among the
entire study sample, assuming the disease
is a long-term, chronic disease with no cure
and assuming no study participants have
died.
34.
35. Practice
Questions
2. Interpret the following risk ratios in words.
a. A risk ratio= 1.0 in a study where researchers
examined the association between consuming
a certain herbal supplement (the exposure) and
developing arthritis.
b. A risk ratio= 2.6 in a study where researchers
examined the association between ever having
texted while driving (the exposure) and being
in a car accident.
c. A risk ratio = 0.75 in a study where
researchers examined the association between
≥ 30 minutes of daily exercise (the exposure)
and heart disease.
36. References
Alexander LK, Lopes B, Ricchetti-Masterson
K, Yeatts KB. Common Measures and
Statistics in Epidemiological Literature.
Epidemiologic Research and Information
Center (ERIC) Notebook. Second Edition.
2015.