Aubrey- Epidemiology Test 2 Flashcards

Question

Autonomy (3)

Answer 1

[4 key principles] Self-rule/ Self-determination Participants must.. -Have full & complete understanding of the risks and benefits (No misinformation, incomplete info, or ineffectively-conveyed info (language or education level)) -Decide for ones-self, without outside influences -No coercion, reprisal, financial manipulation

Answer 2

To benefit or do good for, the patient (not society) | Has to be some benefit even if getting placebo (getting care from doctor, assessment)

Answer 3

Equal and fair treatment regardless of patient characteristics

Answer 4

Do no harm. Researchers must not.. - Withold info - Provide false information - Exhibit professional incompetence

Answer 5

Issued by National commission for protection of human subjects of biomedical and behavior research, decides whether of not research conducted is ethical 1) Respect of persons - Research should be voluntary, subjects autonomous 2) Beneficence - Research risk are justified by benefits 3) Justice - Risk and benefits are equally distrubted

Answer 6

Agreement to participate -Based on being fully and completely informed [mentally-capable and legal consenting age]

Answer 7

Agreement to participate - Based on being fully and completely informed, give by mentally capable individuals NOT able to give legal consent (children) - Requires consent of parent or legal guardian

Answer 8

IRB (before) OHRP (enforce during) DSMB (during)

Answer 9

all human subjects must be reviewed - Full board: ALL interventional trials with more than minimal/ no risk to patients, all medication studies - Expediated: minimal risk and/ no patient identifiers - Exempt: no patient identifiers, low/no risk, de-identified dataset analysis, environmental studies, use existing data/ specimens

Answer 10

agency that administers and enforces regulations

Answer 11

Semi-independent committee not involved with the conduct of the study but charged with reviewing study data as study progresses, to asses undue risk or benefit DURING Can stop study early for either overly-positive or overly negative findings

Answer 12

Patient oriented

Answer 13

Patient-Oriented Individual vs. Combined Surrogate: decreases blood pressure Patient benefit: keeps patient out of hospital

Answer 14

Assessment (measurements) Scientifically-rigorous and standardized Objective better than subjective assessments Valid, accurate, and reproducible

Answer 15

clinical trial, clinical study, experimental study, human study, investigational study

Answer 16

Investigator selects "interventions" Allocates subjects into groups More "rigorous" in ability to show cause and effect

Answer 17

Phase 1 to Phase 4 Population tends to increase Tends to get longer in duration Change in focus as you move up

Answer 18

Phase 1: Safety Phase 2: Effectivness Phase 3: Effectivness Phase 4: Safety

Answer 19

Prior to human investigation | Bench and animal research

Answer 20

``` New drug/ device/ procedure Small N (20-80) Healthy volunteers Assess safety and toxicity, dosing, and pharmcokinetics Short duration (few days to week) ```

Answer 21

New drug/ device/ procedure, indication/ study population Large N (100-300) Utilize patients of interest with condition Expands purpose of Phase 1 safety but assess efficacy Short to medium duration (several months) Narrower inclusion criteria Major flaw is limitation, want any changes to be due to intervention

Answer 22

New drug etc, indication or study population Even large N (1,000-3,000) Patients with condition Determine safety and primary purpose efficacy Longer duration (months to years) Superiority vs non-inferiorty vs equivalence formats Phase FDA mandates before drug approval [Drug with name could still be phase 3 if new condition or drug used in group not approved of when in phase 3 before]

Answer 23

Post marketing Long-term effects (risks/benefits) in large population of diseased Registries, Surveys Drug will always have name if in Phase 4

Answer 24

Cause precedes effect (shows causation) | Only design used by FDA for approval

Answer 25

Cost Complexiy/Time Ethical consideration Generalizability (external validity)

Answer 26

Systemic Review

Answer 27

It takes all studies and put them together so that it appears that there was one large, new study and build a consensus from the meta-analysis

Answer 28

Case reports and case series are just reports of one or more individuals that have had a unique experience; usually hypothesis generated

Answer 29

Desired vs logical vs plausible selection criteria These absolutely impact generalizability Control groups needs to be identical to the case group in every way except for the presence of disease

Answer 30

True, observational and interventional studies use human subjects

Answer 31

Explain impact talk about causation A lot of restrictions These studies not for clinical practice, no room for adjustment So restrictive can't even adjust dosage

Answer 32

Allow flexibility to change dosage and add other drugs Still Interventional studies Key elements -No placebo: practicality, no actually physician uses placebos -Let in the regular people: people with multiple morbidities and drugs -Use own clinical judgements on how they treat their patients

Answer 33

1) Lose the researches control of how the physician prescribes that prescription or manages the patients 2) Lose all of the advantages of the explanatory method [Lock, removal of confounding] 3) Loss of control and rigidity

Answer 34

Simple Factorial Parallel Cross-Over

Answer 35

Divides (randomizes subjects in +2 groups) A single randomization process Commonly used to test a single hypothesis Any number of groups only one randomization

Answer 36

Divides in greater than or equal to 2 groups Further subdivides into each group Randomizes at least twice Takes more people but answers more questions Tests usually at second randomization point

Answer 37

Improves efficiency for answering clinical questions Increase study populations sample size Increase complexity (which may be a barrier to recruitment) Increase risk of drop outs May restrict generalizability results

Answer 38

Groups simultaneously and exclusively managed No switching after initial randomization Can be simple or factorial

Answer 39

Groups serve as own control by crossing over from one intervention to another during study Allows small N Between & Within- Group comparison possible -comparison of A vs B -comparison of seiners on A and seiners on B Forced switching, everybody switches

Answer 40

Period of time to remove first drug from system Could be 1 day to 1 month Can be at beginning or middle Can be part of lead-in phase

Answer 41

All study subjects blindly given one or more placebos for initial therapy to determine "new" baseline elf disease (standardization) - Can assess study protocol - Can "wash out" existing medication - Can determine among to placebo-effect

Answer 42

- Only suitable for long term conditions which are not curable or which treatment provides short-term relief - Duration of study for each subject is longer - Carry-over effects during cross over - Treat-by-period interaction - Small N - Complexity in data analysis

Answer 43

-Differences in effects of treatments during different time periods

Answer 44

Primary Secondary/Teritary/ etc Composite

Answer 45

Most important key outcomes Main research question (hypothesis) Can have multiple

Answer 46

Lesser importance yet still valuable Possible for future hypothesis question Other related info generated from data

Answer 47

Combines multiple endpoints into a single outcome Could be considered primary outcome, and if so, then secondary outcomes may be the individual outcome elements from composite

Answer 48

One person can contribute toe ash of the three individual elements but only counted once in overall amount Usually secondary outcomes are listed as the breakdown composite Followed by non composite secondaries

Answer 49

``` Death Stroke or Myocardial infarction Hospitalization Preventing need for dialysis [Patient centered outcomes are more impactful] ```

Answer 50

``` [Elements used in place of evaluating patient0oriented (direct endpoints] Blood pressure (risk of stroke) Cholesterol (risk of heart attack) Change in SCr (worsening renal function) ```

Answer 51

Can be non-random or random | If random then randomly picked (not randomization)

Answer 52

baseline characteristics Purpose: to make groups as equal as possible Based on known and unknown confounders equality of groups is determined by p values [Can be shown in table format, text statement, key of table]

Answer 53

Simple Blocked Stratified

Answer 54

Equal probability for allocation to one of study groups

Answer 55

Ensures balance within each interventional group Ensure groups equal in size Last person in each block is put where they need to belong to even out groups Someone outside investigation must control this

Answer 56

ensures balance with known confounding variables examples: gender, age, disease severity/duration, comorbidities Can also pre-select levels to be balanced within each interfering factor (confounder)

Answer 57

Single Blind Double Blind Open-Label

Answer 58

study subjects are not informed of intervention Clinicans know Only okay if objective study, researchers have no interaction with patients

Answer 59

No one knows | Someoneoutside investigation controls this

Answer 60

Everyone knows Some studies you can't blind or doesn't matter if patients know Comparing injectable drug with inhaler [would have to have double dummy-placebos]

Answer 61

Post-hoc surverys

Answer 62

Placebo (Dummy) Placebo-effect Hawthorne effect

Answer 63

Inert treatments made to look identical to active treatments | Double dummy if two placebos

Answer 64

improvement in conditions, power of suggestion

Answer 65

desire of patients to "please" investigators by reporting positive results

Answer 66

[Not accepted unless prospectively planned] | Data dredging or fishing

Answer 67

Include them Ignore them Treat them "as treated"

Answer 68

Intent to treat Example: last known assessment carried forward Impact: -Preserves randomization process -Preseves baseline and group balance at baseline which controls for known and unknown confounders -Maintains statistical power (original size sample)

Answer 69

Include only compliant or completing subjects Per-Protocol or Efficacy Analysis -Compliance predefined (80-90%) -Impact of Per-protocol Biases estimates of effect (over-estimates) [reduces generalizability since not including those that could only do 65%]

Answer 70

Ignores group assignments Allows subject to switch groups and be evaluated in grips they moved to, ended in, or stayed in most If they switch or primary care switches to other group by accident

Answer 71

Drug levels Pill counts Bottle counter-tops

Answer 72

- Frequent follow up visits/ communication - Treatment alarms/ notification - Medication blister packs or dosage containers

Answer 73

Be a passive observer of natural events occurring in the individuals with the disease/condition of interest (cases) who are compared with people who do not have conditions (controls) Commonlly generates an Odds Ratio as measure of association

Answer 74

The expected baseline risk factor profile in the population from which the cases are drawn

Answer 75

Disease status

Answer 76

When studying a rare disease or investigating an outbreak

Answer 77

2x2 table Know column totals What we don't know is of those A + C people which will end up in box A and which in box C Compare odds of exposure in the disease compared to nondiseased

Answer 78

- Unable to "randomize" (unethical, Illegal, not feasible) - Limited resources (Time, money, subjects) - The disease of interest is rate - Prospecive exposure data, derived from prospective Cohort study is difficult/expensive to obtain and/or very time inappropriate

Answer 79

Retrospective (always)

Answer 80

Know outcome

Answer 81

- Good for assessing multiple exposures of one outcome - Useful when disease are rare - Useful in calculating odds and Ors - Less expensive than interventional trials and prospective cohorts - Useful when ethical issues limit interventional studies - Useful when dynamic populations [Dont have to worry about loss to follow up] - Useful when disease has a long induction/latent period

Answer 82

Limited by amount of data Worry about misclassifications Worry about have enough data Worry about if disease has changed or exposure has changed

Answer 83

Major determinant in whether any conclusion is valid | Internal validity

Answer 84

Case-control study

Answer 85

Subjects are their own controls during the other times they don't have the acute change in risk Levels of risk changes over the year

Answer 86

Case-Crossover Design

Answer 87

These are case-control studies conducted after, or out of, a prospective COHORT study Subjects in cohort study ultimately develop disease are defined as cases These defined cases used in a new (different) study design Used to evaluate other exposures

Answer 88

Set up on exposure and hunts for outcome

Answer 89

Nested Case-control studies or when "sampling" necessary from Cohort

Answer 90

Survivor sampling Base sampling Risk-set sampling

Answer 91

Sample of non-disease individuals (survivors) at end of study period

Answer 92

Sample of non-disease individuals at start of study

Answer 93

Sample of non-disease individuals during study period at same time when Case was diagnosed

Answer 94

Individual matching Group matching Don't match anything that might be a risk factor

Answer 95

Matches individuals based on specific patent based characteristics Used when have unique and important characteristics

Answer 96

Proportion of cases and proportion of controls with identical characteristics are matched 41% cases are males so 41% of controls are males

Answer 97

Prospective NOT RETRO | Cohort and caes controls are equal in terms of retrospective

Answer 98

To be a passive observe of natural events occurring in naturally-exposed and unexposed groups Useful when studying rare exposure Commonly generates Risk Ratio (RR) as measure of association

Answer 99

Exposure status OR group membership (something in common)

Answer 100

Incidence studies/ Follow up studies/ Longituidinal studies

Answer 101

2x2 Table | Know who were exposed or not, what we don't know is if they got the disease or not

Answer 102

- Unable to "randomize" - Limited resources (more so for prospective) - The exposure of interest is rare - More interested in incidence rates/ predictors of risk for outcome

Answer 103

Prospective, Retrospective, Ambidirectional fashion | Group assignment still based on exposure

Answer 104

Exposure group is selected on the basis of past or current exposure and both groups (exposure and non-exposure) followed into future to assess for outcomes and then compare - Takes longer - Still group allocated based on exposure - It is possible to lose people - Incidence study cause can look at newly diseased

Answer 105

At the start of the study, both the exposure and the outcome of interest have occurred Retrospectively start at time of exposure and follow forward to the point of outcome occurrence in the present Exposure still have to occur before outcome, group allocation based on exposure Know outcomes when starting group but ignore them Downside: at mercy of data available, accuracy and detail

Answer 106

Uses retrospective design to assess past differences but adds all data collect on additional outcomes prospectively from start of study Looking for outcomes in past and future Only am bidirectional study

Answer 107

A group with something in common Birth Cohort: individuals born in same region Inception Cohort: individuals coe to same point (work)

Answer 108

Fixed Closed Open (dynamic)

Answer 109

can't gain members but can have loss to follow up | 911 firefighters

Answer 110

No gain or loss Walled off room with no doors Short term

Answer 111

has new additions and some loss | Framingham heart study, babies added, elderly die

Answer 112

Internal (best): same cohort General population: randomly selected Comparison: least acceptable

Answer 113

Least acceptable Simple attempt to match groups as close as possible on numerous personal characteristics (can't control for other potentially harmful exposures) Find them where you can, make sure not exposed

Answer 114

- Good for assessing multiple outcomes of one exposure - Useful when exposure are rare - Useful in calculating RISK and RR - Less expensive than interventional - Good when ethical issues limit use of interventional - Good for long induction/latent periods (Retrospective) - Able to present temporality (prospective)

Answer 115

-Can obtain greater amount of study info [more control over specific data collection, get more data, can educate patients on what to avoid] -Follow-up/ Tracking of patients may be easier -Better at giving answer to "temporality" -May look at multiple outcomes for one exposure -Calculate incidence and incidence rates

Answer 116

- Time, expense, lost to follow up - Not efficient for rare disease - Not suited for long induction - Exposure may change over time

Answer 117

- Best for long induction/latency conditions - Able to study rare exposures - Useful if the data already exists - Saves time and money compared to prospective

Answer 118

- Requires access to charts, database - "Information" may not factor in or control for other exposures - Patients may not be available for interview or contact - Exposure (or amount) may have changed over time

Answer 119

``` Levels of exposure (stratify) Induction period (interval between exposure and onset) Latency period (interval between onset and clinical diagnosis) ```

Answer 120

Healthy work effect | Selection bias

Answer 121

relationships of health/ disease to other variables of interest at same time aka PREVALENCE Called cross sectional because information gathered represents what is occurred at a point in time or time frame a-cross a large population SNAPSHOT in time Any study with word NATIONAL in it

Answer 122

Focueses simultaneously on disease & population characteristics, including exposure, health status, health care, utilization etc - seeks associations - generates and tests hypothesis - by repetition in different time periods, measure trends

Answer 123

Person, Place, TIme

Answer 124

- Fairly quick and easy to perform for researcher using data (data already collected) - Useful for determining prevalence and risk factors across populations - useful for measuring current health status & planning health services - Useful for evaluation differences in subgroups within populations - Require IRB review but low level expediated

Answer 125

- Prevalent cases may represent survivors (bias) - Difficult to study disease of low freq - Problems determing temporal relationship of a presumed cause & effect (exposure and disease histories taken at same time)

Answer 126

1. Collect data on each member of population | 2. Take same of pop and draw inferences

Answer 127

Assess the health and nutritional status of adults & children Combines interview and physical examinations Interview includes demographic, socioecominic, diet Oversamples greater than 60, african america/ hispancis

Answer 128

CDC interview, personal household contacts, non impatient, dr. offices Not physical screening but data is direct (not from chart) Health of the civilian, non-institutionalized population

Answer 129

reliable information about the provision and use of ambulatory medical care services in US Based on sample of visits to non-federal, office based physicians Dr. offices, free clinics, walk in and out, no inpatient Info from charts

Answer 130

combined study designed to describe national patterns of healthcare delivery in non-federal hospital based settings -discharges of impatient departments, visits to ER, outpatient department, ambulatory surgery centers intergrates 3 previous studies (NHDS, NHSMCS, DAWN)

Answer 131

A state based telephone health survey that collects info on health risk behaviors, preventative health practices, and health care access Monthly collection

Answer 132

``` How well a test can detect presence of disease when in fact disease is present -positivity of test -accuracy in those with disease Sens= YP/ (YP+FN) Sens= YP/ (all diseased) Sens=A/ (A+C) ```

Answer 133

How well a test can detect absence of disease in those that disease is absent Spec= NN/ (NN+NP) Spec= NN/ all non disease Spec= D/ (B+D)

Answer 134

how accurately a positive test predicts the presence of disease PPV=YP/ (YP+NP) PPV= YP/ (total positive test) PPV= A/ (A+B)

Answer 135

how accurately a negative test predicts the absence of disease NPV=NN/ (NN+YN) NPV= NN/ (all negative tests) NPV= D/ (B+D)

Answer 136

proportion of time that a patient is correctly identified as either having disease or not having disease with positive or negative test DA/DP= (YP+YN)/ (All patients)

Answer 137

ratio of the proportion of a given test result (pos or neg) for a person with the disease/ propbabiliy of the same result (pos or neg) for a person without the disease

Answer 138

Probabily of a positive test in the presence of disease/ probability of a positive test in the absence of disease Sensitivity/ (1-specificity) [(A/A+C)/(B/(B+D)]

Answer 139

Probability of a negative test in the presence of disease/ probability of a negative test in the absence of disease 1-sensitivity/ specificity [(C/(A+C)/(D/D+B)]

Answer 140

LR+ >10 to demo most bene | LR-

Answer 141

ROCs receiver operator curves a more efficient way to show a relationship between sensitivity and specificity for test with numerical (continuous) outcomes

Answer 142

Validity | Reliability

Answer 143

ability to accurately discern between those that do and those that do not have the disease Telling the truth

Answer 144

Ability of a test to give the same result on repeated uses Analogous to reproducibility/ consistency A valid test is always reliable, but a reliable test is not always valid

Answer 145

For single-group non-comparisons for incidence rate determination

Answer 146

Lower sample size Increase risk of type 2 error Study populations may not be equal between groups

Answer 147

When you use a multiprobabilty, multistage selection

Answer 148

Probability samples and systemic (convience) samples

Answer 149

Decide on what fraction of population is to be sampled and how they will be sampled

Answer 150

Questionaire/ Surveys | Physical assessments

Answer 151

Take into consideration the number of drop outs

Answer 152

Misclassification

Answer 153

observational

Answer 154

Interventional studies

Answer 155

Odds ratio (OR)

Answer 156

Risk Ratio (RR)

Answer 157

Assocations

Answer 158

a low false negative rate

Answer 159

a low false positive rate