Biostats, Research, Ethics, Forensics, Policy, Epidemiology, Etc. Flashcards
What is attrition bias? How can you reduce it?
Bias resulting from differential withdrawals of participants from different comparison groups. It is a major concern in studies that suffer from unequal loss of participants from different groups which are being compared. To reduce the risk of attrition bias, researchers should practice higher rates of follow-up.
What is lead time bias?
The phenomenon where early diagnosis of a disease falsely makes it look like people are surviving longer. It is often a concern in studies that involve early screening for disease.
What type of bias are case-control retrospective studies commonly susceptible to?
Recall Bias - the tendency among individuals who develop a condition to have better recall of potentially
contributing factors
What is a type I error?
The probability of detecting a treatment effect (difference) when the effect does not exist.
What is a type II error?
The probability of not detecting a treatment effect (difference) when an effect does exist
How does volume of distribution change with age?
As we age, more of our body composition is fat (at lest 30% by the time we are elderly) and muscle mass and water decreases –> this leads to a larger volume of distribution –> causing longer half-life of lipophilic drugs (slower clearance)
Starting at what age can an individual give consent to HIV screening? The CDC has also mandated HIV screening for all patients undergoing treatment for what infection?
13 years old; Tuberculosis
What is a correlation coefficient? What is the range? What do positive/negative correlation coefficients indicate?
1) Measurement of the direction and strength of the relationship between two variables
2) Pearson correlation coefficient is on a scale from -1 to +1. The closer the coefficient is to -1 or +1 shows a strong relationship while close to 0 shows a weak relationship.
3) A positive correlation means that one variable moves the other in the same direction, while negative means it moves the other in the opposite direction.
The method of obtaining a prediction for the value of one variable in relation to another variable is called?
Regression analysis
What is relative risk?
The ratio of the incidence of a condition in those with risk factors to the incidence of the condition in those without risk factors
What is attributable risk?
The absolute incidence of the illness in patients exposed to the condition that can be attributed to the exposure
What is a type 1 (alpha) error?
The null hypothesis (H0) is rejected when it is true. Meaning erroneously concluding the difference between groups is due to an experimental effect when it’s just due to random fluctuation – that a difference was determined when there was no difference at all.
What is a type 2 (beta) error?
Accepting the null hypothesis and rejecting alternate hypothesis when the null hypothesis should be rejected and the alternate hypothesis should be accepted. Plain English: Failing to get a significant result when in truth an effect is present.
What is absolute risk?
The probability of developing a certain disease (or outcome) over a specific period of time. The absolute risk is equivalent to the incidence rate
Absolute Risk (AR) = the number of events (good or bad) in a treated (exposed) or control (nonexposed) group, divided by the number of people in that group
What is confounding?
Confounding occurs when the relationship between exposure and outcome is distorted by the introduction of a third variable
What is the M’Naghten Rule?
A mental disease or defect at the time of the act caused them not to know the nature and quality or the wrongfulness of the act. SIMPLY PUT Capacity to know right from wrong.
The legal concept of _____ allows the state to intervene and act as a surrogate parent for those who are unable to care for themselves or who may harm themselves.
Parens patriae
What are the 4 elements that must be proven for a medical malpractice civil suit/tort?
The 4 D’s: Duty, Dereliction, Damages, and Direct Cause
The right to maintain confidentiality in the face of a subpoena is referred to as?
Privilege (doctor/therapist-patient communications are considered privileged communications which the law protects from forced disclosure on the witness stand –> the right to privilege belongs to the patient and NOT the physician so only the patient may wave this right)
To be found guilty for a socially harmful act/crime, the accused must demonstrate what two findings?
1) Mens rea = evil intent
2) Actus reus = voluntary conduct
What does the term ‘respondeat superior’ mean?
A person occupying a high position in a hierarchy is responsible for those in lower positions
What is ‘substituted judgement’?
When a surrogate decision maker makes aa decision on the basis of what the patient would have wanted, taking into account the patient’s wishes and values.
