MLB Final Questions

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

ANOVA

What are major divide and conquer strategies associated with critical appraisal of the biomedical literature?

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

Two by two frequency tables can be used to compare? a categorical and a quantitative variable two or more quantitative variables two categorical variables two or more categorical variables a categorical and two quantitative variables

two categorical variables

What does the 'p' in p-value stand for and the numeric value indicate? 'publish' the difference observed in test versus control cases and likelihood the finding will last the test of time 'probability' of random variation accounting for the difference observed in test versus control cases 'publish' the difference observed in test versus control cases as significant at the level of the numeric value 'preliminary' but worth publishing the difference observed in test versus control cases so others can know 'probability' that the difference observed in test versus control cases is real and is worth further investigation

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

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

4

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? 20-30 4-100 10-100 4-70 4-30

4-30

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

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

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

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

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

Central tendency and error analysis

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

Cause

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

Abductive

The first and more 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? A. All cases when your explanatory factor variable and outcome factor variable were present B. All cases when your outcome factor variable was present and absent C. All cases when your explanatory factor variable was present and absent D. All cases when both, the one or other, or none of your variables were present E. All cases when your explanatory factor variable and outcome factor variable were absent

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

For quantitative research designs, what are major steps to providing evidence that support a plausible model of factors that are necessary and sufficient for a biomedical condition? A. Observe the frequency at which a candidate factor is present with the condition B. Observe the frequency at which the outcome is present in the absence of the factor C. Observe the frequency at which the factor is present in the absence of the problem D. Coding factors associated with the outcome of interest in quantifiable ways E. All of the above

All of the above

In designing tests of cause and effect of any factor of interest associated with your outcome, what are the possibilities to consider? What role might any factor have in any outcome? A. Necessary but sufficient B. Necessary but not sufficient C. Sufficient but not necessary D. Neither sufficient nor necessary E. All of the above

All of the above

What is a strength and a weakness inherent with the one-way ANOVA statistic? A. Allows statistical comparisons of two or more datasets, but it does not indicate which pair(s) of datasets are likely to have real differences in means B. Allows statistical comparisons of which pair(s) among two or more datasets are likely to have real differences in their means up to as many as 13 datasets C. has built-in Tukey post-hoc tests that allow statistical comparisons of which pair(s) among two or more datasets are likely to have real differences in their means D. allows statistical comparisons of two or more datasets, but requires that the values of each of the datasets are normally distributed E. has built-in Bonferroni post-hoc test that allow statistical comparisons of which pair(s) among two or more datasets are likely to have real differences in their means

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

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? A. Finding the single number summation of the data and how precisely it was determined B. Finding the conclusion of the data and integrating it into other findings in the field C. Analyzing the distribution of the data while suspending judgment as to the conclusion D. Displaying data beautifully pointing to the conclusion of the study based on the hypothesis tested E. Finding any error in the data that would exclude them from being part of a normal distribution

Analyzing the distribution of the data while suspending judgment as to the conclusion

In a few words, how would you define critical thinking or critical reasoning? A. Defining, labeling, and remembering B. Illustrating, comparing, describing C. Analyzing, evaluating, integrating D. Applying, identifying, organizing E. Creating, innovating, theorizing

Analyzing, evaluating, 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

Bias due to subjects lost to follow up

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

Both events will occur together less than half the time

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

Cause of an outcome of interest

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 SD is a complex conception that is not as readily related as the CI is to the estimate of the mean SE is a complex conception that is not as readily related as the CI is to the estimate of the mean range can include outlier values that unnecessarily skew the visualization of the data CIs are part of the 'new statistics' that are designed to improve engagement of the readers

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? A. confidence in how the values of a data trend is easier to grasp than probabilities linked to excluding your hypothesis B. 0.95 confidence that there is a real effect is far more readily understood that the 0.05 probability of no effect in the dataset C. p-value must be combined with other variables to determine the precision of the estimates of the true population means D. CI's are straightforward visual and conceptual relationships to the point estimate of the central tendency of the dataset E. presenting statistics as ranges is always highly preferred over presenting statistics as point estimates in visual displays

CI's are straightforward visual and conceptual relationships to the point estimate of the central tendency of the dataset

The art of science is how to find what would be new, important and soluble. Scientists seek convergence of innovations and infrequent events, over months to years. What thinking connects assumptions, open-minded antecedents and consequents in findings? A. Science leaves nothing to chance B. The early bird catches the worm C. The second mouse gets the cheese D. Chance favors only the prepared mind E. Opportunities are only seldom perfect

Chance favors only the prepared mind

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

Chi-square

Center stage in quantitative research are measures of how dispersed values in a dataset are from its average value. Dispersion from the average value tells you about: A. Confidence in its precision and likely distinctness from the average value of other data sets B. Dispersion is a characteristic property of datasets with a very large n C. Any dispersion measure from a dataset can often be used to identify outliers D. How systematically the research study design that generated the data was performed E. The nature of the statistic in your sample as a correlate of the parameter in your population

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

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

Confidence interval

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

Confidence interval

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

Confidence intervals

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

Confounders

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? A. Confounding factors B. Source of drug C. Why patients enrolled D. Duration of trial E. Patient blood pressure

Confounding factors

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

Control

Most observational research studies typically lead to? A. Hypotheses B. Causalities C. Correlations D. Propositions E. Assumptions

Correlations

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

Design systematically favors one or some study outcomes over other outcomes

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

Diagnostic testing

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

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

What broadly distinguishes qualitative, opposed to hypothesis-driven studies? Discovers, describes, and aims to test and evaluate descriptive aspects of medicine Discovers, describes, and aims to test and evaluate physical and natural laws and processes Discovers, describes, and aims to understand psycho-social dynamics and meanings Qualitative research aims to classify the categories of medicine and medical practice Qualitative research only involves the acquisition and analysis of patient narrative data

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

What distinguishes qualitative research and qualitative variables? A. Qualitative research has the number of situations, which are mathematically meaningful, of all the psychosocial interactions under exploration. Qualitative variable data has no mathematical meaningful numbers in the categories under exploration B. 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, usually narrative or images, of qualitative research. C. Qualitative research has no numbers that are mathematically meaningful. Qualitative variable data has the number of cases, which are mathematically meaningful, which are scored for each category of the qualitative variable. D. Qualitative research simply gather information on a topic or small group of topic of interest without any practical aims. Qualitative variable data is a major part of the information collected in the course of qualitative research studies. E. Qualitative research uses numbest such as those in Likert Scale in order to convert qualitative research into quantitative research. Qualitative variable data does not use numbers except to label categories, which have no mathematical meaning.

E (?)

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

Easily calculated as arithmetic average and more sensitive to extreme values

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

Effect size and confidence intervals

What are major components to a logical argument that results from applying the Scientific Method? A. a thesis claimed or hypothesis B. a rationale for the hypothesis C. Evidence from testing the hypothesis in experience D. Alternative explanations or alternative interpretations of the evidence E. A model of what the findings mean

Evidence from testing the hypothesis in experience

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

Experimental outcomes demonstrate that the assumption cannot hold true

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

Explanatory and response variables

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

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

A factor is present in region 1 and absent in region 2. A disease is absent in region 1 and prevalent in region 2. What would favor studying the factor naturally occurring in region 1 versus as an intervention in region 2? A. Exposure of factor to a given subject is known and potential effect measured shortly after B. Factor when naturally available from the environment is less subject to erroneous artifacts C. Randomization of the intervention is absent, so either study would be equally effective D. Another factor than study factor from region 1 might be blocking disease so neither study E. There should be more events of the factor's action in region 1 therefore the observational study

Exposure of factor to a given subject is known and potential effect measure shortly after

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

Five number summary

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

Fraction of healthy people correctly identified as not having the condition Specificity is also called true negative rate -- looks at how false positives skew your negative results

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

Fraction of sick people correctly identified as having the condition *Sensitivity is also called true positive rate -looks at how the false negatives skew the positive results

A data set of values of a single qualitative variable provides what kind of information? Data for constructing and analyzing a scatter plot Frequency of cases in any of two or more categories Frequency data for performing matrix operations Information to turn qualitative into quantitative research Data for constructing and analyzing a frequency histogram

Frequency of cases in any of two or more categories

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

Harm exposure

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?

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

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

Hypothesis supported by test outcomes explains results far beyond originating field

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

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

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

Imaginative combining of thoughts to explain a problem

The scientific method generates new knowledge by testing claims of such by experience. If results of tests exclude the claim, discard it and find another. If results support the claim, continue to use and test it. What are major cognitive steps involved? A. Collecting facts and systematically classifying them B. Observation and letting the dots connect themselves C. Statistical thinking and power analysis D. Imaginative hypothesis generation and critical reasoning E. Breaking down something into its parts and rebuilding it

Imaginative hypothesis generation and critical reasoning (i.e. the method and logic of biomedicine)

Francis Bacon, often referred to as a pioneering philosopher of the scientific method, did much to define its underlying logic. However, what was a most critical component that Bacon said little if anything about? A. Reasoning from the particular results of observations and experiments to a general conclusion B. Consulting with colleagues investigating associated subjects in the same or similar disciplines C. Communicating findings in publication following an inductive logical interpretation of the results D. Interleaving of free imagination with precedent and coherent reasoning to explain model investigated E. Gut feelings as the leap in understanding underlying the process going from hypothesis to conclusion

Interleaving of free imagination with precedent and coherent reasoning to explain model investigated

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

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

Intervention and the control

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

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

Mean differences or correlations

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

Meta-analysis analyzes the results whereas systematic review reviews them

What are five numbers of the boxplot often featured in exploratory data analysis? A. Mean, mode, median, standard error of mean and standard deviation of data B. Mean, standard error of mean, standard deviation, minimum, and maximum of data C. Minimum, maximum, mean, 5% of the range, and 95% of the range of the data D. Minimum, maximum, median, and first quartile, and third quartile of a data E. Sum of all data values, number of all values, mean, minimum, and maximum of data

Minimum, maximum, median, and first quartile, and third quartile of a data

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

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

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

Necessary but not sufficient to establish causal relationships

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

Order-dependence of intervention and outcome

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

Outcome is absent at the beginning of a cohort study

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

PICOT

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 source of bias in this approach? A. Investigators always present a biased viewpoint in the presentation before the survey B. The location where the survey is conducted will always bias too much the results C. When survey are made easy to take, people tend not to say what they really think D. People who are highly opinionated will be over-represented in the survey results E. Most of the people taking the survey will not know the subject and will answer randomly

People who are highly opinionated will be over-represented in the survey results

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 of causality E. Confusing conditional interdependence based on association with independence

Predicting the future given presence of one of the two factors thought to be so related

Hypothesis generation classically is best defined by which of the following? Analysis of a claim for the assumptions and principles associated with it Application of experimental techniques in tests and analyzing the results Emphasis of emotional intuition in open-mindedness applied to a problem Preparation of precedence, incubation, and illumination Verification of an observation by systematically altering what causes it

Preparation of precedence, incubation, and illumination

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

Presence of the intervention is a predictor of the outcome

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

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

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? A. Precision of the parameter mean of an outcome variable from confidence intervals B. Standard error of the mean from an outcome variable of interest and a control variable C. Prior probability calculated from previous experiments or observations related to the study D. Number of events of an outcome of interest in sample along with the law of large numbers E. Standard deviation from an outcome variable of interest together with a control variable

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

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

Prior probability from other studies

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

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

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

Qualitative

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

Random noise

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

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

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

Recall bias by subjects

What features are the most important advantages of interventional designs over observational design in research studies? A. Multiple time points closely follow the time of the first intervention B. Multiple comparator groups to determine the primary intervention's effectiveness C. The number of subjects, objects, or events for the controls is greater than 30 D. The number of subjects, objects, or events for the tests is greater than 30 E. Removal of the intervention to measure the reversibility of the outcome effect

Removal of the intervention to measure the reversibility of the outcome effect

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 Research to determine whether or not the intervention approach makes a difference Research in the social sciences because the subjects always involve observations Research on a topic whose investigation by an interventional study would be expensive Research with many variables as they only can be tracked all together by observing

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

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

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

What is the broad goal of an Interventional Study? A. Associations among outcomes and factors influencing those outcomes B. Identification of a specific hypothesis for testing in clinical trials C. Linear regression to positively or negatively associate factors with disease outcome D. Retrospective reviews of patient cases to look for opportunities to intervene E. Test for cause and effect relationships between measured outcomes and their causes

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

What makes a question a scientific hypothesis? A question is a scientific hypothesis if it is theoretically logical Analyzable by the syllogistic format of antecedent-consequent parts Answerable by looking into the published literature in a scholarly field Testable by experience in a way that it is possible to be excluded The question must be shown to be of interest to groups of people

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

What part of research study data results in probabilistic thinking being necessary? A. Precision of measured values varies in any study so there is no way they are absolutely correct B. Scientific data can never be proved beyond some doubt so better to think probabilistically C. Systematic bias on the research design or performance of the research design of the study D. The accuracy of measured values from scientist to scientist and from lab to lab varies E. The outcome being measured can be conditionally dependent on the independent variable

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

Why bother with statistics? What do statistical tests of significance tell us generally? A. Shows whether the difference in means or the correlation of the data sets is big or small under 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 the association likely results from variability in measuring outcomes D. How accurate are the means or the correlation given the precision and conditions to measure outcomes E. How incisive the intervention was taking into consideration the conditions used to measure outcomes

To what extent the difference in means or the association likely 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

Two or more factors have a conditional relationship

What is an example of a biased sample in a research study? You perform a research study and find that 72% of people go to baseball games You perform a research study and find that 98% of people use the internet daily You set out to find whether all people like you and you report on only the people who do You set out to find whether all people run at least once weekly, 18% do, 82% do not You test for the presence of lead in water from natural springs, 45% do, 55% do not

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

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

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

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

What are major advantages of using graphs that display box plots of a quantitative outcome for each of multiple qualitative explanatory variables in a quantitative research study? A. Central tendency in the mean and spread in the standard error for each dataset and visual comparisons of means for effect sizes and standard errors for preciseness of measurements across all explanatory factor variables B. central tendency in the median and spread in interquartile range for each dataset and visual comparisons of medians for effect sizes and IQR for preciseness of measure across all explanatory factor variables C. Simple focus on the central tendency of the median and spread in the data of the IQR in the bar graphs that do not distract by showing or characterizing in any way the whole range of data values from each categorical set D. Central tendency in the mean and spread in standard deviation for each dataset and visual comparisons of means for effect sizes and standard deviations for preciseness of measurements across all explanatory factor variables C. Simple focus on the central tendency of the mean and spread in the data of the standard error of the mean in the bar graphs that do not distract by showing or characterizing in any way the whole range of data values from each categorical set

central tendency in the median and spread in interquartile range for each dataset and visual comparisons of medians for effect sizes and IQR for preciseness of measure across all explanatory factor variables

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? conditions where the candidate cause and other comparator causes are recorded conditions where the two parameters' values are recorded and analyzed comparative conditions of absence, varied amount, concentrations, or frequencies comparative conditions of geography where the two sites are completely separate first one parameter is observed and the other parameter is checked and then vice-versa

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

What are the reasons why a patient who tests positive for a disease does not necessarily have a 100% probability of actually having the disease? A. diagnostic tests have a substantial rate of true negatives B. the prevalence in the population of any disease is not 100% C. diagnostic tests have a significant rate of false negative D. diagnostic tests have a substantial rate of true positives E. diagnostic tests have a significant rate of false positives

diagnostic tests have a significant rate of false positives

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? are the units of the parameters standardized? Is x the cause of y? do the data points indicate a unimodal distribution? Is the distribution curvilinear? do the data points fit a y = mx + b line? Is x the cause of y? do the data points linearly align? If so, is the line sloping upward or downward? do the data points form clusters? Are the two clusters overlapping?

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

The student's t-test boils down to a ratio of what statistical variables over what other statistical variables? A. weighted average of the ranges of the datasets normalized by the effect size B. effect size normalized by the weighted average of the ranges of the datasets C. weighted average of experimental error normalized by effect size D. effect size normalized by the weighted average of experimental error E. total range of the confidence intervals divided by the medians of the datasets

effect size normalized by the weighted average of experimental error

aseline 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 only after the intervention is applied in parallel with and only before the intervention is applied in parallel with and specifically at the time of intervention in parallel with and specifically at the outcome measure endpoints in parallel with and before and after the intervention is applied

in parallel with and before and after the intervention is applied

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 inter-quartile range median and standard deviation mean and inter-quartile range mean and range median and range

median and inter-quartile range

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 exponential cumulative log normal geometric

normal

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

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

Given the deluge of daily publication in biomedicine, what will be your primary strategies to ensure that you learn important advances in your field for your patients and research?

structured approach based on a structured question, and choosing study designs appropriate to that 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 shows that confounding factors of physical activity play a role in obesity explanatory variable, calories per breakfast, indicates good nutrition prevents obesity study is an observational study and therefore on its own the findings of cause are flawed explanatory variable, calories per breakfast, predicts satiety thereby lowering eating later in day breakfast foods have a lesser proportion of empty calories causing decreased obesity

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