Research/Stats/Ethics Flashcards
(38 cards)
1
Q
Sensitivity
A
- Good screeNing test but can have false positives
- Negative results are really reliable, positive results are not as reliable
- seNsitivity have reliable Negatives (CAN RULE OUT DISEASE!)
- Probability that the test will produce a true positive when used on a population with the disease
= TP / (TP + FN) —– true positives divided by everyone with the disease
2
Q
Specificity
A
- Positive results are really reliable, negative results are not as reliable
- Good Confirmatory test (to determine treatment) but can have false negatives
- sPecificity have reliable Positives
- Probability that the test will produce a true negative when used on a population without the disease
= TN / (TN + FP) —- true negatives divided by everyone without the disease
3
Q
Positive Predictive Value
A
- Probability that someone who tests positive actually has the disease and isn’t a false positive
- Most useful when the prevalence is high (PPV increases as prevalence increases)
= TP / (TP + FP)
4
Q
Negative Predictive Value
A
- Probability that someone who tests negative actually does not have the disease and isn’t a false negative
- Most useful when prevalence is low
= TN / (TN + FN)
5
Q
P value definition
A
- Chance that the null hypothesis was rejected in error
- Odds that the null was correct and the results were due to chance
6
Q
Type I error
A
- Rejected the null hypothesis in error
- Probability of a type I error is the same as the p value
7
Q
Type II error
A
- Accepted the null hypothesis in error
8
Q
Validity
A
- Whether a test actually measures what it’s intended to measure
- Internal validity reflects accuracy
- External validity reflects generalizability
9
Q
Reliability
A
- Consistence or repeatability of scores
10
Q
Intention to treat
A
- All patients remain in the original groups to which they were initially randomly assigned in the study
11
Q
Number needed to treat
A
- Number needed to treat to prevent one adverse effect
- NNT = 1 / absolute risk reduction
- Absolute risk reduction = rate in untreated group - rate in treated group
12
Q
Incidence
A
Newly diagnosed cases in a given period of time
13
Q
Prevalence
A
Total number of cases of disease existing in a population at a given time
14
Q
Standard error
A
Describes how accurate the sample mean value used in the analysis is compared to the true population mean value
15
Q
Confidence interval
A
Measure of the reliability of your result
16
Q
Pre-test probability
A
Best estimate of the probability that a condition is present before you start diagnostic testing
17
Q
Likelihood ratio
A
Likelihood that a person who has the condition will have a positive test result
- LR > 1 increases the probability that the target condition is present
- LR < 1 makes condition less likely
18
Q
Absolute risk
A
Dividing number of patients who develop disease by total patients exposed
= A / (A+B)
19
Q
Relative risk
A
Probability of an outcome in the exposed group to the probability of the outcome in an unexposed group
= (A / (A+B)) / (C / (C+D))
20
Q
Odds ratio
A
Odds of an outcome in one group compared to the odds of that outcome in another group
= (A/B) / (C/D)
21
Q
Order of best study types
A
- Systematic reviews, meta analysis
- Randomized, controlled trials
- Cohort studies
- Case control studies
- Cross sectional studies
- Case studies/case reports
- Expert opnions/editorials
22
Q
Randomized control trial benefits
A
- Blind study, randomly assigned
- Baseline groups are equal, no confounding variables
- Limits expectation bias of patient and reduces bias of interpreting results
23
Q
Cohort studies
A
- Compare a group with an exposure to a control group without an exposure
- Limitations: need large sample size and long time to do they study
24
Q
Case control studies
A
- Compare patients with the disease and patients without disease and then check for risk factors
- Risk factor has to come before the outcome
- Useful only with a small sample size, a long latency period, or a rare outcome
25
Cross sectional studies
- Observational, good for looking at associations between two measured factors at one point in time
- Limitations are risk of confounding variables and results can't be used to infer causality
26
Systematic reviews
Require: specific clinical question, thorough search for studies, clear explanation for which studies were considered and which were not, descriptive results section summarizing the findings
27
Definition of brain death
Patients in a coma lack wakefulness and lack awareness of self environment. Patients in a vegetative state lack awareness but do have wakefulness.
28
Sibling donor rules
Both donor and recipient are to benefit (mostly psychological to donor so if sibling has severe cognitive disabilities they are not going to benefit), risk to donor is minimal, absence of coercion
29
Maternal-fetal conflicts
- Autonomy and bodily integrity of mother is critical and must be honored
- Can't legally force a mom into a C-section for any reason
30
Assent
- Willingness to accept treatment
| - It is preferred for kids to agree to the treatment but since they're minors, it's not required like consent
31
Newborn screening guidelines to include disease
- Disease should have a significant deleterious effect on the child, have effective treatment available if diagnosed early, have a screen that is acceptable to the population
32
Newborn screening positives/negatives
High rate of false positives so need more definitive testing (but can also have some false negatives)
33
Ethics for correcting ambiguous genitalia
- Decision should be multidisciplinary approach
- Possibility of gender change in adulthood should be factored in and surgery should be reversible if possible, fertility should be preserved if able
34
Ethics for HIV positive patients
- Disclose slowly over time to child
- Participation in close contact sports where blood and bodily fluid transmission is likely is not recommended
- It is NOT mandatory for parents to disclose a child's positive HIV status to the school
35
Children exposed to domestice violence are at risk for
- Physical injury
- Aggression with their peers
- Separation anxiety as toddlers
- School failure as adolescent as well as risky sexual behavior
36
Foster care health rules
- Health screen should be done within 72 hours of placement into foster care
- Comprehensive health assessment within 30 days
37
Most common type of medical error
Medication error
38
Disclosing medical errors to family
- Be totally transparent, why it happened, how it will impact them, steps being taken to prevent it from happening again
- Shown to reduce litigation and decrease settlement amounts
