Behavioral Science/Stats Flashcards
Study type that establishes prevalence
Cross-sectional
Case-control study measure?
Odds ratio (What was “odd” about their history?)
Case-control study design?
People with disease v. people without disease. Looking for prior exposure or a RF
Cohort study measure?
Relative risk (Increased risk for disease)
Cohort study design?
People with exposure v. people without exposure
Twin concordance study design?
Frequency of disease between twins
Pharm phase I asks?
Is it safe? Safety, toxicity, pharmacokinetics
Pharm phase II asks?
Does it work? Efficacy, dosing, AE’s
Pharm phase III asks?
Is it as good or better?
Pharm phase IV asks?
Can it stay? Post-marketing surveillance
Sensitivity =
TP / (TP + FN) = Pr (T+|D+)
Specificity =
TN / (TN + FP) = Pr (T-|D-)
PPV =
Pr (D+|T+) = TP / (TP + FP)
NPV =
Pr (D-|T-) = TN / (TN + FN)
Prevalence is related to incidence how?
Prevalence is approx incidence rate x avg disease duration
Incidence rate =
of new cases in specified time period / population at risk during same time period
Odds and Probability related how?
Odds = Pr / (1-Pr) ; Pr = O / (1 + O)
What parameters are only dependent on the test itself?
Sensitivity, specificity, likelihood ratio
Odds ratio and relative risk?
OR = (a/b) / (c/d) = ad/bc; RR = [a / (a+b)] / [c (c+d)]
RRR =
1 - RR
Difference between effect modification and confounding bias?
Effect modification is something to be studied; Present when effect of the main exposure is modified by presence of another variable.
Power
= 1 - Beta; Beta = Pr(type II error) = Pr of rejecting null hypothesis when it is truly false = Pr difference when there IS one = Maximize for clinical trials!
Type 1 v. type 2 error
1st and foremost, making something out to be when there isn’t anything. (Rejecting H0 when it is true). 2nd, saying nothing when there is (Fail to reject, when H0 is false)
Berkson’s bias
Selection bias - selecting hospitalized patients as the control
Hawthorne effect
The tendency for a study population to affect an outcome due to the knowledge of being study. e.g. behavioral studies
Pygmalion effect
Researcher’s beliefs in efficacy of treatment potentially affecting the outcome
Number needed to harm?
1/AR
Precision vs. accuracy?
Accuracy has to do with close to REAL number. Precision has to do with ability to REPRODUCE a result
Lead-time bias vs. recall bias?
Lead-time bias occurs when the early detection of a condition is interpreted as increased survival. Recall bias is when awareness of the condition leads to increased recall (e.g. retrospective studies)
Observer-expectancy bias?
The Pygmalion effect - researcher’s belief in efficacy changes outcome of treatment
Standard deviation vs. standard error of the mean?
SD is variability from mean of a set of values. Standard error is variability between sample mean and true population mean. SEM = SD / sqroot(n)
Positive vs. negative skew?
Skewed is tail. Positive tail is long. Negative skew has longer negative tail.
What is statistical power?
The probability of rejecting the null hypothesis WHEN IT IS FALSE = 1-Type II error (Beta = false-negative)
Primary vs. secondary disease prevention?
Preventing disease occurrence and screening for EARLY disease
Tertiary vs. quaternary disease prevention?
Tertiary screening is treating to reduce disability 2/2 disase. Quaternary is ID’ing patients at risk from unnecessary treatment.
What things can children get treatment for without parental consent?
Contraception, STDs, pregnancy, drugs, emergency/trauma
Priority of surrogate decision making?
Spouse, adult children, parents, adult siblings, other relatives.
APGAR stands for?
Appearance, Pulse, Grimace, Activity, Respiration.
When should you be worried about APGAR?
4-6 = assist and stimulate. < 4 = resuscitate
Definition of low birth weight?
<2500 g
Number of words by age 2?
- 2-word sentences
Number of words by age 3?
- Complete sentences
When should a kid be able to kick a ball?
Age 2
When does a kid form core gender identity?
Age 3
When does a kid hop on one foot?
Age 4
When does a kid have cooperative play and have imaginary friends?
Age 4
when does a kid have stranger anxiety vs. separation anxiety?
6 mo and 9 mo
When does a kid lift up head while prone?
1 mo
When does a kid lose the moro reflex?
3 mo
When does a kid lose the Babinski reflex?
12 months
When does a kid lose the palmar reflex?
6 months
When does a kid pass toys from one hand to the other?
6 months
When does a kid point to objections?
12 months
When does a kid lose rooting reflex?
4 months
Schizoaffective disorder
Requires psychosis W/o mood symptoms for at least 2 weeks.
Big difference between anorexia and bulimia?
Bulimics maintain their body weight and don’t have amenorrhea, osteoporosis, emaciation
How to determine if something is a confounding variable?
Stratify your analysis with the confounder to see if there are still an effect of the exposure onto the outcome.
