Combined Questions 11/10

What kind of research is better done using an observational study design?

Research on a topic whose investigation by an interventional study would be unethical

What makes a question a scientific hypothesis?

Testable by experience in a way that it is possible to be excluded

A "convenience" sample can generate a large number of events. An issue of broad appeal is presented to people in a high traffic area, popular internet site/ place on campus, with option to take a survey. What is the likely bias to this approach?

The location where the survey is conducted will always bias too much of the results

What part of research study data results in probabilistic thinking being necessary?

The outcome being measured can be conditionally dependent on the independent variable

Most observational research studies typically lead to? a. hypotheses b. causalities c. correlations d. propositions e. assumptions

c. Correlations

What does the 'p' in p-value stand for and the numeric value indicate?

'probability' of random variation accounting for the difference observed in test verses control cases

Which of the following acronyms could be used as a rough outline to a clinical science article? A FINER B PICOT C ANOVA D IGOR E PULSE

B PICOT

What broadly distinguishes qualitative, opposed to hypothesis-driven studies?

Discovers, describes, and aims to understand psycho-social dynamics and meanings

A great way to visualize both the central tendency and spread in a data set? A Three number summary B Four number summary C Median and range D Mean and range E Five number summary

E Five number summary

What comes to mind when you think of schema & illness scripts, and models & diagnoses?

Exploratory data analysis and confirmatory data analyses respectively.

With pre-test probability of 30% how does a positive versus a negative outcome on a perfect diagnostic test (very high sensitivity and very high specificity) change a clinician's confidence that the patient has the disease and should begin treatment?

Negative outcome would indicate not proceeding with treatment

In biomedical studies, the p-value assesses the probability that the data in question can be the result of random variability alone. What beyond the p-value is needed to assess the probability that the data results from the hypothesis being investigated?

Prior probability calculated from previous experiments or observations related to the study

When reading the primary biomedical literature, clinicians and scientists should be..?

Skeptical

Medical errors mostly arise during the diagnostic process. It can be extraordinarily complex with many aspects going from a patient to a timely, accurate, explanatory diagnosis. Where exactly is the problem in the diagnostic process?

clinical reasoning

Which of the following is not part of exploratory data analysis? A Confidence intervals B Median C Inner quartiles D Range E Data distribution

A Confidence intervals

In the study of biomedical outcomes of interest, a factor can be identified that shows association with the outcome. Often the evidence is a correlation in which the factor is associated with the outcome in greater than 90% of all observations conducted. Which one of the following factors is most likely to have no real causal effect, indirect or direct, on an outcome of interest? A Confounder B Modifier C Stratifier D Satisficer E Distractor

A Confounder

Optimizing healthcare for the most people generally increases costs for all involved and budgets are limiting. At academic medical centers, critical and scientifically creative thinking often plays a fundamental role in fulfilling medicine's oath to optimize healthcare for the most people. How might this best be done? A Create equally or even more effective treatment at lower cost B Require insurers to pay a greater fraction of the cost of healthcare C Require patients to pay a greater fraction of the cost of healthcare D Create choices for patients to opt out of expensive treatment E All of the above

A Create equally or even more effective treatment at lower cost

Which of the following best defines big data? A Data that are very large scale and gathered, distributed, and analyzed across locations B Data that are very large contained within an individual computing environment C Data that are very large whose analysis and interpretation have big implications D Data that are very large and contained within electronic patient health data records E Data that are very large scale and accumulating since the beginning of cloud storage

A Data that are very large scale and gathered, distributed, and analyzed across locations

How are differential diagnoses typically refined to the initial primary diagnosis? A The patient's chief complaints B History and physical examination C Lab tests and problem lists D Initial illness scripts E None of the above

C Lab tests and problem lists

There are two major types of data analysis in quantitative research studies. One is confirmatory data analysis. The other is exploratory data analysis. What best characterizes the aim of exploratory data analysis? A Present with clarity the central tendency of the data and statistical error B Graph the data in forms that cause the viewer to quickly conclude the study C Tabulate or graph study data in a beautiful way that appeals to the viewer D Present the data in open-minded ways that reveal what the data might mean E Present the confirmatory data analysis on your study as the first step

D Present the data in open-minded ways that reveal what the data might mean

What combined with the P-value can indicate how likely your hypothesis is false? A Inverse probability of null hypothesis B Dispersion of preliminary data C Probability of null hypothesis D Prior probability from other studies E Standard error of the means

D Prior probability from other studies

The annual rate of medical errors in US healthcare is which of the following? A 1 % B 2 % C 4 % D 8 % E 16 %

E 16 %

What is the broad goal of an Interventional Study?

Test for cause and effect relationships between measured outcomes and their causes

What is the rate of MI in smokers and non-smokers according to the Cohort Study data in the pre-class module? 78 per hundred smokers and 9 per hundred non-smokers over ten years of the study 10 per hundred smokers and 5 per hundred non-smokers over on average 50 years of life 5 per hundred smokers and 10 per hundred non-smokers over on average 50 years of life 10 per hundred smokers and 5 per hundred non-smokers over ten years of the study 5 per hundred smokers and 10 per hundred non-smokers over ten years of the study

10 per hundred smokers and 5 per hundred non-smokers over ten years of the study

Student's t-test is a statistic that is one of the most common procedures in science and medicine. The t-test is the most common statistic of significance used when comparing the mean of two samples of quantitative, normally distributed data sets. The t-test provides statistical analysis of the difference in sample means normalized to the standard error of difference of sample means. The numerator relates to the explanatory variable, whereas the denominator relates to the random noise in the study results. The t-test is special and distinct from other statistics, in particular as opposed to the z-statistic or other statistics, because the t-statistic is valid for small samples. What is the n number of independent samples in a study where the t-test should be used to analyze the probability of the difference between the means of two samples being due to chance alone?

4-30

Probabilistic thinking is very important to evidence-based medicine on an everyday level. This way of decision making relies on the strength to which two or more features are correlated or independent of one another. If two independent events each has a probability of 0.7, what is most likely? A Both events will occur together less than half the time B One or the other event will occur at any given time C Both events will occur together more than half the time D Both events will occur together 70% of the time E Neither will occur greater than 10% of the time

A Both events will occur together less than half the time

What is generally the most informative measure of error in a data set? A Confidence interval B P-value C Error of the mean D Standard deviation E Median

A Confidence interval

Most medical errors result from which of the following? A Diagnostic errors in the formulation and accurate identification of the medical problem B Trivial errors and other mistakes that anyone could make due to inattention to details C Challenging number of complications due to chronic diseases in their late stages D Lack of knowledge about some rare diseases, injuries, and other medical problems E Errors in the effective use of advanced medical systems and information technologies

A Diagnostic errors in the formulation and accurate identification of the medical problem

Statistical tests are not generally intuitive which leads to a lot of confusion as to what these tests tell us about research measures. The concept and meaning of P-values are not well understood generally, including by investigators who use P-values routinely, but must be if we are to decrease the rate at which we publish research studies that turn out to be false. A Student's t test in a study giving a P-value of 0.001 means ...? A Difference between means has a 1 in 1000 chance of being random variability B The hypothesis being tested has a 999 in 1000 chance of being true C The difference in means is highly unlikely to be reproducible D The hypothesis being tested has a 1 in 1000 chance of being true E The research study has a 999 in 1000 chance of being true

A Difference between means has a 1 in 1000 chance of being random variability

Massive data analysis from public health records indicate that one person infected with the SARS-CoV-2 virus productively infects on average more than one person. This fact logically explains which of the following characteristics of the Covid-19 disease? A Exponential growth B Linear growth C Linear decay D Constant incidence E Exponential decay

A Exponential growth

In a cohort study design what are the minimal cohorts and their outcomes? A Exposed and not exposed at start & disease and not disease at end B Exposed with disease at start & not exposed without the disease at end C Exposed without the disease at start & and not exposed with the disease at end D Disease and no disease at start & exposed and not exposed at end E Disease and no disease at start & exposure is determined retrospectively

A Exposed and not exposed at start & disease and not disease at end

What makes a hypothesis potentially innovative rather than simply new? A Hypothesis supported by test outcomes explains results far beyond originating field B Hypothesis supported by test outcomes is important enough to publish C Hypothesis supported by test outcomes can lead to results in a device that is useful D Hypothesis supported by test outcomes for the very first time in the world E Hypothesis supported by test outcomes corroborates multiple previous publications

A Hypothesis supported by test outcomes explains results far beyond originating field

Understanding outcomes of interest in medicine can involve interrogating observations and conditions giving rise to those outcomes in terms of plausible causal models. A critical question often arises as to whether a factor that correlates with the medical outcome of interest is a direct and major cause or an indirect correlation. Which one of the following factors is most likely to have a real but indirect cause on an outcome of interest? A Modifier B Confounder C Stratifier D Satisficer E Distractor

A Modifier

It is best to design and perform case-control studies so ...? A Past conditions of exposure to harm are similar for cases and control subjects B Allocation in the case and control groups is randomized at start of study C Case and control subjects are randomly paired so outcomes average out D Candidate factors are measured with techniques specific to each subject E Case subject-specific and control subject-specific factors are investigated

A Past conditions of exposure to harm are similar for cases and control subjects

The long-term effect of chemical hazards in the workplace can be initially difficult to detect let alone characterize in terms of easily measured outcome on say blood work or organ physiology. Nevertheless, public health research has developed methodology that can identify these hazards and either remove them from the workplace or minimize exposure to them of workers. Which of the following can be done to improve the conditions of the workplace;? A Perform retrospective survival analysis of workers in workplaces with the hazard present or absent B Perform prospective survival analysis of the workers after adding the hazard to the workplaces C Perform a survey analysis on if workers think the candidate hazard is harmful in workplaces with it D Perform a survey analysis on if workers think the candidate hazard is harmful in workplaces without E Perform a cross-over design study on workers using both the candidate hazard and a placebo control

A Perform retrospective survival analysis of workers in workplaces with the hazard present or absent

Covid-19 modeling reflects the centerpiece of scientific methodology and reasoning in medicine. What aspect of the Covid-19 modeling best reflects scientific methodology and reasoning in public health best practice? A Reciprocally fitting of actual Covid-19 case, death and geographical spread variable values with theoretical model parameters B Averaging massive data across all countries of the world taken together to monitor the trends in Covid-19 cases and deaths C Following general principles of virology and infectious disease to avoid getting lost in the weeds of SARS-CoV-2 and Covid-19 D Focusing effort and resources on disruptive imagined therapeutics to provide public health communication and policies E Modeling Covid-19 infectious disease variables by fitting them to known precedence of historical SARS-CoV-1 model parameters

A Reciprocally fitting of actual Covid-19 case, death and geographical spread variable values with theoretical model parameters

When studying factors and biomedical outcomes of interest, what key concept below reflects strong evidence for the role of the factor in the outcome A Reversibility of the outcome under conditions when the factor is removed B Presence of the factor under conditions when the outcome is absent C Presence of the factor under conditions when the outcome is present D Absence of the outcome under conditions when the factor is absent E Presence of the outcome under conditions when the factor is absent

A Reversibility of the outcome under conditions when the factor is removed

What is a major difference between a systematic review and a meta-analysis? A Statistical aggregation of data from different studies are pooled B Conceptual depth of a meta-analysis is greater than a systematic review C Only systematic review presents evidence for its completeness D Only meta-analysis considers assumptions of the studies reviewed E Meta-analysis analyzes the results whereas systematic review reviews them

A Statistical aggregation of data from different studies are pooled

What would you think most plausible of a drug whose mechanism of action is to bind and stimulate receptors of cells in the body? A The effect in response to the drug will saturate at a particular maximum concentration of the drug B The effect in response to the drug will increase as long as the concentration of the drug increases C The effect in response to the drug will randomly increase with increase in concentration of the drug D The effect in response to the drug will randomly decrease with increase in concentration of the drug E The effect in response to the drug will be exponential with increase in concentration of the drug

A The effect in response to the drug will saturate at a particular maximum concentration of the drug

Strong evidence of temporality consistent with a causal relationship between a drug and a medical outcome include which of the following? A The greater the concentration of the drug the faster the increase of the effect response B The greater the concentration of the drug the greater the magnitude of the effect response C The response to the drug is absolutely dependent upon the presence of a second factor D The change in the medical outcome occurs in the presence of the drug, never in its absence E The change in the medical outcome always fails to take place in the absence of the drug

A The greater the concentration of the drug the faster the increase of the effect response

Geographical information systems (GIS) are being used at a greater frequency in healthcare over the last decades. A multi-state GIS-based health study featuring zip code analyses found that, independent of wealth and health insurance, there exists a graded spectrum of access to healthcare according to the zip code of not only your home but also of your work. Which of the following is likely to be most generally true. A The nearer the hospitals from home and work, the better access to care B The farther the hospitals from home and work, the better the access to care C The nearer the hospitals from home and work, the worse access to care D The nearer the hospitals to industrial factories, the worse access to care E The farther the hospitals to industrial factories, the worse access to care

A The nearer the hospitals from home and work, the better access to care

In an epidemiological study of an infectious agent outbreak, cases of infection are analyzed section by section of the greater city region and a single geographical section is determined to be the hotspot having the most number of cases, five-fold more than any other section. The authors of the study conclude that the origin of the infection must be in the hotspot section. Which if the following is a critical aspect of the analysis? A The number of infected people must be compared to the number of people living in the section B The number of infected people must be compared to the size of the physical area of the section C The number of infected people must be compared to the time that they spent in the section D The number of infected people must be compared to the time that they spent outside the section E The number of infected people must be compared to the rainfall that was received in the section

A The number of infected people must be compared to the number of people living in the section

Why do physicians make sure that they know the epidemiology of the diseases in his or her area of practice?

A centerpiece of epidemiology is the prevalence which is important in properly interpreting diagnostic test results

You prospectively study 60,000 patients with cancer triggered by two independent exponential growth processes. If either one, the other, or both processes are required for the cancer what would be the shape of the cumulative cancer cases over time?

A exponential rise verses an initial first slow then fast exponential rise in cancer cases.

What aspects of the outcomes of an observational clinical study of two factors could suggest support for a causal relationship between them?

A large number of cases when both factors F and O were observed together, a large number of cases when O was observed in the absence of F, and a few cases where F was observed in the absence of O

The first and most important step in scientific thinking is to test whether your explanatory factor variable and your outcome variable are coincidental. What do you need to test for independence in your data?

All cases when both, one or the other, or none of your variables are present

Answering the simplest most straightforward question of survival data, "what was the average survival time of patients with disease X?" turns out at the analysis level not so simple and straightforward at all! what complicates survival analysis?

All of the above, Alive patients art the end of the study, patients who die from a different cause, patients physically unable to participate in the study, patients deciding not to continue to be a part of the study.

How might how long it takes an infectious agent to shed in one infected person to infect another person, how many people one person typically infects, mobility of people, reporting combine to influence the rate of change in the prevalence of infections?

All of the above, can spell after a lag of weeks, daily doubling of cases too late to stop. prevalence of infections can double quickly if the agent has high infectivity, non recorded areas, long time to demonstrate disease, people travel who are infected

When surrogate endpoints are used, which of the following properties might they have in an RCT?

All of the above, cost far less to measure compared to measuring the actual clinical outcome in the patient, be an early change for shorter trials, dose relationship, actual clinical outcomes

In designing tests of cause and effect of any factor of interest associated with your outcome of interest, what are the possibilities to consider? What role might any factor have in any outcome?

All of the above, necessary and sufficient, necessary and not sufficient, sufficient but not necessary, neither sufficient or necessary

For quantitative research designs what are major steps on the way to providing evidence supporting a plausible model of what factors are necessary and sufficient for a biochemical condition to occur?

All of the above, observing frequency of the factors with the condition, without the condition, factor is present without the problem, and coding factors associated with the outcome

Why are case-control study designs so much more frequently used over other research study types for associating candidate causes of rare diseases?

All of the above, participants have the disease, lowlihood of developing disease, prospective RCT are impractical, qualitative studies not suited for variables.

What do the big data of COVID-19 infections and death tell us about the SARS-CoV-2 virus and Covid-19?

All of the above, public health challenge, medicine will take a while to create, virology has significantly increased in the last decades, not accurately measured effects of the virus

How does COVID disease show us that health care is social?

All of the above, social determinates of health matter, change meeting with friends and family, change public meetings, covid effects everyone and shows health disparities.

What concepts are important in evaluating evidence for cause and association, over coincidence?

All of the above, strength of evidence, reproducibility, specificity, temporality, biological gradient, biomedical plausibility and coherence, intervention.

Which of the following contribute to mis-diagnoses leading to death or serious harm in the US today? Narrow diagnostic focus with failure to establish a differential diagnosis Failure to appreciate and reconcile relevant symptoms, signs, or test results All of the answers contribute to mis-diagnoses Misinterpretation of diagnostic studies (imaging, pathology, etc Failure or delay in ordering a diagnostic test

All of the answers contribute to mis-diagnoses

What is a strength and a weakness inherent with the one-way ANOVA statistic?

Allows statistical comparisons of two or more data sets but it does not itself indicate which pair(s) of data sets are likely to have real differences in means

when teachers and students are asked what is critical thinking most typically they go on for many minutes describing it. In a few words how would you define critical thinking or critical reasoning?

Analyzing, Evaluating, and Integrating

In prognostic research studies, what issue comes into play for diseases whose onset have long latencies? A Under-sampling errors B Bias due to subjects lost to follow up C Specificity of diagnostic test D Sensitivity of diagnostic test E Internal validity of study design

B Bias due to subjects lost to follow up

What is a statistic to analyze variation in measures of two categorical variables? A t statistic B Chi-square C ANOVA D Distractor E Distractor

B Chi-square

What concept is now used to indicate how likely the mean is what you think it is? A P-value B Confidence interval C Range D Inner quartiles E Median

B Confidence interval

Random allocation is a critical design component in scientific research studies. What does random allocation in large research studies minimize? A Gender differences B Confounders C Baseline rates D Perceptual bias E Blindedness

B Confounders

Central tendency is a statistical analysis that determines a single value as representative of an entire data distribution. What is an advantage and a disadvantage of the mean versus the median as a measure of central tendency of a data set? A Everybody knows what it is and requires calculation of the error of the mean B Easily calculated as arithmetic average and more sensitive to extreme values C Always the best measure of central tendency and requires a computer to determine D More resistant measure of the central tendency and includes weight of outliers E Quantifies variability in the data and inaccurate in small data sets with outliers

B Easily calculated as arithmetic average and more sensitive to extreme values

An assumption by definition is not tested in research studies, often times is not even identified at the onset of the study, but occasionally becomes a game changer as the study progresses. How might an assumption unexpectedly become the main test of an experimental study? A Experimental outcomes demonstrate that the assumption must hold true B Experimental outcomes demonstrate that the assumption cannot hold true C Control conditions yield the same results as the experimental conditions D Control conditions give different results than the experimental conditions E Experimental conditions demonstrate that the assumption must hold true

B Experimental outcomes demonstrate that the assumption cannot hold true

What are the two most important endpoint questions for studies about therapy? A How many test subjects and how many control subjects in the study? B How large was the treatment effect and how precisely was it measured? C Was the study conducted at multiple sites and equal participants at each site? D Was the principle investigator and the statisticians blinded to test and control groups? E Was a cross-over research study design used and alternative sequences tested?

B How large was the treatment effect and how precisely was it measured?

What accounts for the assessment that most claimed research findings are false? A Study designs are not the correct type given the nature of the research question posed B Most experiments are under-powered and P-values acceptable for publication too high C Selection of positive results before study publication and repeated study publication D Not using any statistical tests of significance in published reports of research outcomes E Most experiments are not independent and when they are results are not aggregated

B Most experiments are under-powered and P-values acceptable for publication too high

The best clinical research design is the Randomized Control Trial (RCT). At the heart of RCTs is an intervention and an outcome of interest. What is the logical role of the intervention in RCTs? A Correlation of the intervention with the outcome measured B Presence of the intervention is a predictor of the outcome C Baseline rate in the same type of experiments will be zero D P-value in the present and future will be less than < 0.05 E Outcome is the cause in a cause-and-effect relationship

B Presence of the intervention is a predictor of the outcome

The Scientific Method is the best strategy we have for generating new knowledge about the world. The critical and creative thinking processes of the Scientific Method are used not only in medicine but also in law and in business. What best defines the Scientific Method? A Objectively collects data, organizes it into categories and publishes the organization B Proposes useful or predictive claims about the world and tests them by experience C Generation of theories which are logically valid about how the world works D Applies emotional intuition to problems in the world to come up with solutions E The set of all methods that scientists use to for the acquisition of all data

B Proposes useful or predictive claims about the world and tests them by experience

Student's t-test is a statistical test to determine the likelihood that ...? A Your hypothesis that you were testing accounts for your research study results B Random variability linked to your measures can account for the research study results C Your research study results are statistically indistinguishable from those of students D Your experimental measurements are normally distributed and therefore trustworthy E An unusual sample is likely to be the factor accounting for your research study results

B Random variability linked to your measures can account for the research study results

What are semantic qualifiers? A Ambiguous terms that are impossible to quantify and use to distinguish diagnoses B Terms that are abstractions of the patients description of their symptoms and signs C Differing terms or phrases describing the same illness script by various healthcare people D Codes used by healthcare workers to describe dangerous or other extreme conditions E Terms used whose ambiguity leads to errors by less successful healthcare workers

B Terms that are abstractions of the patients description of their symptoms and signs

Which of the following properties of proteins and pathways of the human body are exhibited in the relationship between exposure and outcome variables of observational clinical research studies?

Before increases in magnitude of exposures to the maximum occurs the changes in the outcome measure reaches an extreme and does not change further

The shape of data distributions is a major focus of Exploratory Data Analysis. The shape provides clues to not only the nature of the sampling performed but also the nature of the population. A plausible source of data values for a bimodal distribution would be ...? A Weight in grams of all Haas avocados harvested from a farm in a season B Time in minutes it takes you to drive to school sampled over a year C A large random sample of heights of all adults from across the US D Average precipitation in a major US city for each month across the year E Average length of daylight hours in US for each day across the year

C A large random sample of heights of all adults from across the US

What do interventional studies aim to research? A Correlation of factors and outcome of interest B Patterns that do not occur spontaneously C Cause of an outcome of interest D Natural factors and outcomes of interest E Propositions to test as hypotheses

C Cause of an outcome of interest

A research design is biased under what conditions? A Only when statistical analysis is omitted completely from the research study B When the intervention allocation is randomized with respect to control allocation C Design systematically favors one or some study outcomes over other outcomes D Design does not include randomization and blindedness of investigators E When the figures and tables do not include results from exploratory data analysis

C Design systematically favors one or some study outcomes over other outcomes

What are synonyms for causes and effects in research studies? A Confounders and outcomes B Parameters and values C Explanatory and response variables D Interventions and controls E Placebos and comparators

C Explanatory and response variables

In diagnostic testing, specificity refers to ...? A Fraction of healthy people incorrectly identified as not having the condition B Fraction of sick people correctly identified as having the condition C Fraction of healthy people correctly identified as not having the condition D Fraction of sick people correctly identified as not having the condition E Fraction of healthy people incorrectly identified as having the condition

C Fraction of healthy people correctly identified as not having the condition

Exclusion and inclusion criteria aim to optimize the possibility that ...? A Intervention and control groups are adequate in number for the study B Statistical tests of significance are the most relevant for the study C Intervention and control groups have the same prognosis at study start D Therapy intervention tested in the study has the best chance of success E Blindedness occurs at the level of therapy administration and outcome analysis

C Intervention and control groups have the same prognosis at study start

A gold standard in research design is the Randomized Control Trial (RCT). The design features to deal with confounding factors that might contribute to the outcome. In an RCT what gets randomly allocated? A Intervention and the trial B Trial and the control C Intervention and the control D Confounder and the intervention E Confounder and the control

C Intervention and the control

At best the findings of an observational study are ...? A Necessary and sufficient to establish causal relationships B Sufficient but not necessary to establish causal relationships C Necessary but not sufficient to establish causal relationships D The basis for hypothesis-driven research studies E The basis for quantitative research studies

C Necessary but not sufficient to establish causal relationships

What distinguishes a cohort from a case-control study? A Outcome is absent at the beginning of case-control study B Outcome has just presented at the beginning of a cohort study C Outcome is absent at the beginning of a cohort study D Outcome has just presented at the start of a case-control study E Control subjects are present in case-control and absent in cohort studies

C Outcome is absent at the beginning of a cohort study

What is a major limitation of case-control studies of decades-long exposure harm? A Cases matched with other cases B Data coding and analysis C Recall bias by subjects D Controls matched with other controls E Cases more interesting than controls

C Recall bias by subjects

Why bother with statistics? What do statistical tests of significance tell us generally? A Shows if the difference in means or correlation of data sets is big or small under the study conditions B Shows whether or not the differences in means or the correlation shown have any practical importance C To what extent the difference in means or association results from variability in measuring outcomes D How accurate are the means or the correlation given precision and conditions to measure outcomes E How incisive the intervention was taking into consideration the conditions used to measure outcomes

C To what extent the difference in means or association results from variability in measuring outcomes

Probabilistic thinking comes into play in the Scientific Method most frequently when? A Conclusions of the research studies have yet to be proven B Signs and symptoms are not 100% known by a physician C Two or more factors have a conditional relationship D Experimental methods are not completely understood by the investigator E Studies have explicitly stated caveats that prevent conclusions

C Two or more factors have a conditional relationship

When presenting figures showing analysis of your data, the 95% CI is preferred over the range, SD, and SE assessing your data values because:

CI is an easily understood indicator of how precise the mean of the values was determined

What are the advantages of presenting estimates of variability of a research study by 95% confidence intervals rather than P-values?

CIs are straightforward visual and conceptual relationship to the point estimate of the central tendency of the data set(s)

What are the major advantages of using graphs that display box plots of quantitative outcome for each of multiple qualitative explanatory variables in a quantitative research study?

Central tendency in the median and spread in interquartile range for each data set and visual comparisons and contrasts of medians for effect sizes and interquartile range of preciseness of measures across all explanatory factor variables

What are over-arching topics to analyze and evaluate in any grant, publication, or scientific critique?

Claim Rationale Evidence Alternative Meanings (CREAM)

Clinical reasoning is often said to be similar to basic science reasoning in that in both types of reasoning hypotheses can play major roles. How is clinical science different than basic science reasoning? Clinical reasoning begins with the consequent and the antecedent is generated in the diagnosis Basic science reasoning can begin with the antecedent and the consequent is generated in the results Deduction is a required step in clinical reasoning and is optional in basic science reasoning Clinical reasoning involves abduction and deduction and basic science reasoning only abduction Deduction is an optional step in clinical reasoning and is required in basic science reasoning

Clinical reasoning begins with the consequent and the antecedent is generated in the diagnosis

What is the major distinction making Cohort studies at least by design better than Case-Control studies? Cohort studies are prospective with participants not having the disease or medical condition at the onset of the study Case-Control studies are retrospective with participants having the disease or medical condition at the onset of the study Case-Control studies are prospective with participants not having the disease or medical condition at the onset of the study Cohort studies are prospective with participants having the disease or medical condition at the onset of the study Cohort studies are retrospective with participants having the disease or medical condition at the onset of the study

Cohort studies are prospective with participants not having the disease or medical condition at the onset of the study

What feature distinguishes a cohort from a case-control study in such a way that makes the strength of evidence to be stronger by design in the former, compared to the latter study type?

Cohort studies are prospective, whereas Case-Control studies are retrospective

Center stage in quantitative research are measures of how dispersed values in a data set are from the average value. Dispersion from the average value tells you:

Confidence in its precision and likely distinctiveness from the average value of other data sets

Large drug trials have numerous variables including wide ranging differences in the patients enrolled. When comparing the outcome of a drug trial on patient groups what can be difficult or impossible to know yet can alter outcome measures.

Confounding factors

Statistical analysis of a categorical study of two groups needs what minimal number of cell counts of data? A 30 B 2 C 16 D 4 E 8

D 4

What logic is most closely associated with the Scientific Method? A Theoretical B Inductive C Deductive D Abductive E Practical

D Abductive

Deliberate critical thinking underlying successful clinical reasoning features which of the following: A Imagination, free-association, horizontal thinking B Emotional intuition, expert intuition, strategic intuition C Excellent recall, comprehension, and transfer application D Analysis, evaluation, interpretation, and integration E Creativity, inverse thinking, inductive generalization

D Analysis, evaluation, interpretation, and integration

In interventional studies the intervention is presumed to be ... ? A Moderator B Effect C Modulator D Cause E All above

D Cause

The baseline rate is determined in what design part of a research study? A Follow-up B Intervention C Enrollment D Control E Kinetics

D Control

Which of the following is methodologically similar to basic science hypothesis testing? A Specificity analysis B Evidence-based medicine C Sensitivity analysis D Diagnostic testing E Qualitative research

D Diagnostic testing

In diagnostic testing, sensitivity refers to ...? A Fraction of sick people incorrectly identified as not having the condition B Fraction of healthy people correctly identified as not having the condition C Fraction of sick people incorrectly identified as having the condition D Fraction of sick people correctly identified as having the condition E Fraction of healthy people correctly identified as having the condition

D Fraction of sick people correctly identified as having the condition

Hypothesis generation is best characterized by? A Imaginative gut feelings that are put in question form B Critical analytical reasoning in order to conclude C Critical evaluative thinking in order to conclude D Imaginative combining of thoughts to explain a problem E Applying concepts in new way to get different results

D Imaginative combining of thoughts to explain a problem

The hallmark global research study of the Experimental Method is? A Qualitative study B Observational study C Quantitative study D Interventional study E Control study

D Interventional study

What best conveys the magnitude of the outcome of interest important to the research study? A Explanatory variable size B P-values and sample sizes C Cause or dose size D Mean differences or correlations E Standard error of the mean

D Mean differences or correlations

What makes interventional research studies so powerful? A Incisiveness of an intervention makes it expedient B Intervention tested must be the cause of the outcome C A control is used as a reference comparison D Order-dependence of intervention and outcome E Designed studies are more powerful than natural studies

D Order-dependence of intervention and outcome

What is a critical decision for clinicians in the initial steps of the diagnostic decision making process?

Does the patient presentation clearly fit a likely known diagnosis or does it require careful analytical judgement?

Factors A and factor B are known to occur independently of each other in each of the 50 US states. You observe factor A and factor B to be highly correlated in California but independent of each other in Iowa. Which of the following would be the most likely explanation for your observations? A A directly causes B in Iowa but has no effect in California B A directly causes B in California but has no effect in Iowa C B directly causes A in California but has no effect in Iowa D B directly causes A in Iowa but has no effect in California E A and B in California are each caused by C, but C is absent in Iowa

E A and B in California are each caused by C, but C is absent in Iowa

A statistic used when a study needs to compare three or more groups is ...? A t-test B PICOT C FINER D Chi-Square E ANOVA

E ANOVA

Public health physicians bridge science, medicine, and society arguably more than any other professionals. Which of the following best distinguishes their work? A It's about groups not individuals B It's about geographic features C It's about demographic features D It's about health conditions E All of the above

E All of the above

You observe an association between two variables beyond what can be attributable to the play of chance. What aspects of the association should be considered before interpreting the association is causation? A The presence of one variable increases enormously the frequency of another variable B The association is observed consistently, repeatedly, by different investigators, at different times C The association is observed in different places, at different times, under different circumstances D One variable can be characterized as appearing before, the horse, and the other after, the cart E All of the above

E All of the above

"The human brain is a complex organ with the wonderful power of enabling man to find reasons for continuing to believe whatever it is that he wants to believe." Evidence-based medicine recognizes awareness of such bias as the first step in correcting it. When a bias is identified by a decision maker, a deliberate decoupling from mindless medical decision making to critical thinking for better clinical reasoning can occur. What are the major cognitive biases that lead to diagnostic errors in medicine? A Availability and confirmation bias B Base rate neglect and commission bias C Framing and search satisfying D Anchoring and premature closure E All the above

E All the above

What else provides strong evidence that association between two variables is likely explained by a cause and effect relationship? A The frequency of one variable increases the frequency of the other variable B The concentration of one variable increases the amplitude of the other variable C The quantitative relationship between the variables is biologically plausible D The variables show specificity, not generally occuring in all conditions and people E All the above

E All the above

Where is big data analysis having its greatest breakthroughs? A Retrospective analysis of interventions and outcomes in healthcare B Precision medicine of changes in tumor genomics over time per patient C Functional magnetic resonance brain imaging over multiple sessions per patient D Ultra-high-resolution microscopy visualizing cell biology in time and space E All the above

E All the above

The Diagnostic Method underlying clinical thinking is thought to share major cognitive processes with the Scientific Method underlying scientific thinking. Which of the following are most important to both? A Assessment of variability followed by excluding noise from the data B Affective domain processes roles in the underlying decision making C Big data acquisition, analysis, and interpretation across multiple sites D Systematic team record keeping methodology and communication E Differential hypothesis generation, testing, analysis, and interpretation

E Differential hypothesis generation, testing, analysis, and interpretation

Published research studies are often complex with lots of design, performance, and outcome parts. What are ultimately the most important study outcomes? A Normal distribution and cluster analysis B Standard deviation and P-value C Number of samples and power analysis D Controls and error of the mean E Effect size and confidence intervals

E Effect size and confidence intervals

What best describes the conceptual workings of a scientific grant or article? A Nature of question studied, novelty, expertise of investigators, and number of samples B Title, abstract, introduction, materials and methods, results, discussion, references C Questions in field, null hypothesis significance testing, results, discussion, references D Null hypothesis tested, methodology of experiments, P-values, and limitations E Hypothesis, rationale, precedence, evidence, alternative views, meaning for field

E Hypothesis, rationale, precedence, evidence, alternative views, meaning for field

Hypothesis-driven research cannot be? A Interventional B Case-controlled C Cohort controlled D Observational E Qualitative

E Qualitative

Recently, the following has changed in the Evidence-Based Medicine pyramid: A Authoritarian reviews have been moved higher than cohort-controlled studies in the pyramid B Cross-sectional studies have moved higher than cohort-controlled studies in the pyramid C Case-controlled studies have moved higher than cohort-controlled studies in the pyramid D Critically appraisal of medical topics have moved higher than meta-analyses in the pyramid E Systematic reviews & meta-analyses are a way of viewing evidence from primary studies

E Systematic reviews & meta-analyses are a way of viewing evidence from primary studies

Unlike confirmatory data analysis (statistical hypothesis testing), Exploratory data analysis embraces the two major principles of critical reasoning. What principles are embraced by the Exploratory Data Analysis?

Finding the conclusion of the data and integrating it into other findings in the field.

What is most likely locality size to optimize use of geographical information systems (GIS) resources for preventative medicine by health systems?

GIS analyses that automatically indicate health outcome changes of two standard deviations from average for any given country very local locality compared to other localities within and outside of the patients localities

Baseline rates are important to understand whenever doing an intervention study because the rate might be contributing to the measured effect. When should you control for baseline rate effects by making multiple outcome measures in the absence of the intervention?

In parallel with and before and after the intervention is applied

Francis Bacon often referred to as the pioneering philosopher of the scientific method, did much to define its underlying logic. However, what was the most critical component that

Interweaving of free imagination with precedent and coherent reasoning to explain the model investigated.

What are major strategies of critically appraising an outcome of interest topic in the medical literature?

Investigate the type of research designs and study types that are most relevant to your structured question

Conditional probabilities can make differential diagnostic hypothesis testing of a patient representation daunting. What strategies for the clinical reasoning process can greatly simplify the process?

Look for must have features and rejecting features associated with leading illness scripts

Values of infection fatality rates (IFR) of Covid-19 are: All of the other answers Underestimates of the true IFR because the total number of cases is overestimated Overestimates of the true IFR because the total number of cases is underestimated Accurate because the true IFR is independent of varying treatment patients receive Accurate because the true IFR is independent of varying patients' immune response

Overestimates of the true IFR because the total number of cases is underestimated

what distinguishes qualitative research and quantitative variables?

Qualitative research aims at improving the quality of care or the workplace without trying to test a hypothesis requiring mathematical operations . Qualitative variable data is the information using narratives or images of qualitative research

excluding observational designs, what is the hierarchy of research studies using experimental designs, from best to worse?

Randomized control studies, non randomized control trials, non-controlled interventional trials

When smoking is constant there continues to be a variation in cancer outcomes. A second factor's presence increases outcomes. A third factor associates with cancer but its presence or absence does not alter cancer outcomes. What could be going on?

Second factor is a modifier and third factor is a confounder

Clinical thinking and reasoning is a centerpiece skill for clinicians today not least in part for its role in minimizing medical errors and optimizing patient outcomes. Patient presentations, case representations and diagnostic tests are processed by clinicians by two interactive types of thinking, non-analytic and analytic. Which of the following hold true for these cognitive processes. System II thinking is automatic, easy, fast, and subject to bias System II thinking is deliberate, easy, slow, and accurate System II thinking is automatic, intuitive, fast, and abductive System I thinking is automatic, effortless, fast, and subject to bias System I thinking is automatic, easy, slow, and accurate

System I thinking is automatic, effortless, fast, and subject to bias

What is best to distinguish the use of the terms epidemic and pandemic? The locality of the health condition The agent underlying the health condition The severity of the health condition The host-range of the infectious agent The public response to the health condition

The locality of the health condition

Given the deluge of daily publications in biomedicine, what will be your primary strategy to ensure that you learn important advances in your field for your patients, research, or both?

Use an approach based on structured questions and study designs and types appropriate to those questions

A patient's case can have many facets making the process of analyzing and evaluating the details complex. To deal with this complexity physicians learn to develop a strategic, often deliberately staged, cognitive approach of divide and conquer at the broadest level of categories to characterize the potential diagnosis for a patient. Which of the following is one of the earliest chunks in the clinical reasoning process? Use of semantic qualifiers Consult with a specialist Lab tests Treatment plans Use of illness scripts

Use of semantic qualifiers

What is an example of a biased sample in a research study?

You set out to find whether all people like you and you report on only the people who do

The fact that most diseases are rare tells you that: a diagnostic test must have good sensitivity a positive diagnostic test result is likely to be true a positive diagnostic test result is likely to be false a diagnostic test must have good specificity a negative diagnostic test result is likely to be false

a positive diagnostic test result is likely to be false

Which of the following describe big data? High variety data that include large number of variables and their values High velocity data that grow massively and are analyzed in real-time or quasi-real time High volume data that cannot be stored in single desktop or mainframe computers Data identifying major problems, evaluating their solutions and resources for improvement All of the Above

all of the above

Without a well-formulated question, we are likely to search data bases for: hours or even days the too good to be true irrelevant facts and figures wherever it may lead all the other answers and more

all the other answers and more

At the stage of analyzing and evaluating the one or the few articles that survived your triage in Critical Appraisal, answering facets of your major formulated question and associated questions can be easier, faster, and more effective, taking advantage of the fact that: re-investigating the questions on the net and critiquing more articles on the issue are always options answers to the types of questions you will need to answer are located in typical sections of the article reading the article(s) from beginning to end is a systematic way of not missing any important detail the single most important section of any medical research article is the Materials and Methods section the single most important section to evaluate of any medical research article is the Discussion section

answers to the types of questions you will need to answer are located in typical sections of the article

Simply pointing out a high correlation between selected factors are too frequently interpreted to be in a cause and Effect relationship. This can be due to our minds being predisposed to...? a. knowing that highly correlated factors must be in a cause and effect relationship b. predicting the future given presence of one of the two factors thought to be so related c. interpreting the correlation between two factors as necessary for causality d. interpreting the correlation between two factors as independent for causality e. confusing conditional interdependence based on association with independence.

b. predicting the future given presence of one of the two factors thought to be so related

What are likely the best sources for evidence supporting best clinical practice and what makes them so? pharmaceutical and biotechnology company publications communicating sponsored data on devices and drugs in advertisements pharmaceutical and biotechnology company publications communicating sponsored data on devices and drugs in biomedical journals biomedical journals reviewed by fellow clinicians and scientists published based on strength of evidence and reasoning internet sites designed and edited by the companies owning them to make profit and offering some sampling of self-selected evaluators authoritative review articles written by investigators whose development of the devices and drugs have been company sponsored

biomedical journals reviewed by fellow clinicians and scientists published based on strength of evidence and reasoning

To provide sufficient evidence supporting a cause-and-effect relationship between two quantitative variables, values of the outcome of interest variable is measured under what conditions of the candidate cause variable?

comparative conditions of absence, varied amount, concentration, or frequencies

what are the reasons why a patient who tests positive for a disease not necessarily have a 100% probability of actually having the disease?

diagnostic tests have a significant rate of false positives

In simple analyses of survival of subjects exposed to harm in research studies, such as a Kaplan-Meier analysis, what kinds of variables can be addressed?

dichotomous variables

Taking an Exploratory Data Analysis approach to see if there is any pattern of association between values from two parameters from an observational research study, you plot the values on a scatter plot. What are the most important questions to ask when looking at all scatter plots?

do the data points linearly align? If so, is the line sloping upward or downward?

After triaging the medical literature based on your PICOT question, while investigating the full article, what are you focusing on for evaluating the strength of the findings?

effect sizes and associated confidence intervals

A data set of values of a single qualitative variable provides what kind of information?

frequency of cases in any two or more categories

The scientific method generates new knowledge by testing claims of such by experience. If results of a test exclude the claim, discard it and find another. If results support a claim, continue to use and test it. What are the major cognitive steps involved?

imaginative hypothesis generation and critical reasoning

You are analyzing the interplay among variables in observational research studies and preliminary results suggest that there might be two independent variables changing your outcome measure. One of the independent variables always changes the outcome measure regardless of the presence or absence of the second independent variable. Interestingly, the second outcome variable no matter how altered in magnitude or duration and frequency, does nothing to the outcome measure in the absence of the first independent variable. What is the likely role of the second independent variable? secondary dependent variable totally unrelated to the outcome variable independent modifiable variable totally unrelated to the other independent variable independent confounding variable

independent modifiable variable

Robustness is an important concept in EDA and descriptive statistics referring to measures of central tendency and spread in a data set or in multiple data sets being compared and contrasted. Which of the following are the most complete and robust measures characterizing data sets?

median and interquartile range

What are five numbers of the boxplot often featured in exploratory data analysis?

median, 1st quartile, 3rd quartile, minimum, maximum

What features are the most important advantage of interventional designs over observational designs in research studies?

multiple comparator groups to determine the primary intervention effectiveness

You are the analyst collecting data from 100 international hospital sites each studying the exponential decay of tumor mass after applying a promising anti-tumor immunotherapy by plotting the size of the tumor by invasive imaging each week over the course of the six month study. Each site reports weekly to you the mean size of 100 or more of its patients' tumors, with each patient's tumor normalized to the initial size immediately before the drug intervention. Each week, the means of the fractional size of the tumors from the 100 hospital sites should show what kind of frequency distribution?

normal

Hypothesis generation classically is best defined by which of the following?

preparation of precedence, incubation, and illumination

What was a critical methodological design feature of the RCT study on prevention in the pre-class module? the study perfectly balanced the number of participants allocated to the gold standard vaccine and to the new experimental vaccine the study focused on adult participants thus avoiding ethical issues that might be a concern with pediatric participants no participant in either the experimental or gold standard cohort in the study which covered a 5-year interval were lost to follow-up the study recruited participants from a single country to ensure that confounders could not unknowingly effect outcomes prognostic risk factors were assessed and found to be comparable between the experimental and comparator cohorts

prognostic risk factors were assessed and found to be comparable between the experimental and comparator cohorts

The time and effort spent searching data bases for biomedical articles can be cut ten-fold by first choosing to search based on: a search of a handful of the highest profile authors that publish clinical research articles specific kind of clinical article specified by descriptors of the relevant type of clinical question a blast search of all kinds of articles clinical and basic science so that nothing is missed a search of a handful of the highest profile journals that publish clinical research articles a serendipitous search with general open-minded terms to expand the topic maximally

specific kind of clinical article specified by descriptors of the relevant type of clinical question

You are reading a study that uses an observational study design to look at how feeding school children big breakfasts lowers obesity. The study looked at households in New York City only surveying the weight of school children and the size in calories of their breakfasts over a five-year period. The study's chief finding made headlines because it was surprising and seems counter-intuitive. Which of the following about the study is most likely to be true?

study is an observational study and therefore on its own the findings of the cause are flawed

Two by two frequency tables can be used to compare?

two categorical variables

What would have been the Odds Ratio if the women in Europe aged 50-80 years on the combination drug therapy with hip fractures were 100 and without hip fractures were 1500, and what does that tell you about the influence of potential inaccuracy in the recording or reporting of the presence or absence of hip fractures due to recall bias or confounders? use of the combination drug therapy reduced the likelihood of hip fracture by 67% and the likelihood is very sensitive to misclassification of rather few subjects compared to the total subjects in the study use of the combination drug therapy reduced the likelihood of hip fracture by 33% and the likelihood is largely insensitive to misclassification of rather few subjects compared to the total subjects in the study use of the combination drug therapy reduced the likelihood of hip fracture by 33% and the likelihood is very sensitive to misclassification of rather few subjects compared to the total subjects in the study use of the combination drug therapy reduced the likelihood of hip fracture by 67% and the likelihood is largely insensitive to misclassification of rather few subjects compared to the total subjects in the study use of the combination drug therapy reduced the likelihood of hip fracture by 50% and the likelihood is sensitive to misclassification of rather few subjects compared to the total subjects in the study

use of the combination drug therapy reduced the likelihood of hip fracture by 33% and the likelihood is very sensitive to misclassification of rather few subjects compared to the total subjects in the study

What is likely the best time period needed to stay ahead of SARS-CoV-2 in localities yet to have significant clustering of Covid-19 cases? 28 days 14 days 7 days 1 day 21 days

14 days

What are two major concepts commonly used in biomedical statistics? A Central tendency and error analysis B Bootstrapping and k statistics C Data mining and bias D Stationarity and confidence intervals E Causation and cluster analysis

A Central tendency and error analysis

Dual process theory in medical decision making refers to A Grounded theory qualitative processing versus hypothesis-driven quantitative processing B Automatic, fast, intuitive pattern-recognition versus deliberate, slow, analytical reasoning C Lower order memory thinking skills versus higher order creative thinking skills D Analytical unpacking into parts versus evaluation, synthesis, and integration E Imaginative, outside the box hypothesizing versus deductive syllogistic reasoning

B Automatic, fast, intuitive pattern-recognition versus deliberate, slow, analytical reasoning

What is a statistical factor altering precision in parameter measures? A Categorical differences B Natural variations C Random noise D Measurement accuracy E Calibration bias

C Random noise

Which medical topic is inappropriate to investigate by randomized controlled studies? A Physical therapy B Diagnostic test C Drug therapy D Harm exposure E Medical device

D Harm exposure