Behav/Biostat 1 Flashcards
What is the major limitation of a cross-sectional study?
Cross-sectional study simultaneously measures exposures and outcomes. But the temporal relationship b/w exposure and outcome isn’t always clear. In other study designs, a certain time period separates the exposure from the outcome.
Describe a cohort study.
A group of people who do not have the disease of interest are grouped according to their exposure status and then followed to assess for the development of the disease.
What bias does Matching address?
Matching is used in case-control studies to address Confounding. It involves selecting variables that could be confounders and then matching these variables in cases and controls so that both groups have similar distribution.
In a patient w/ Panic disorder, what do you give to offer rapid relief?
Rapid relief is given w/ Benzodiazepines. Long-term management includes SSRI, SNRI, or CBT.
What is a known medical cause of major depressive disorder?
Untreated hypothyroidism can cause major depression. TSH levels should be checked in patients w/ suspected major depressive disorder.
What type of study design involves analyzing population data as opposed to individual data?
Ecological study looks at the frequency of a given characteristic and a given outcome using population data (ex. Vit D intake and multiple sclerosis in a multi-population study).
When looking at the range of a confidence interval, how is the result determined as statistically significant?
If the range of the CI doesn’t include the null value, then the result is statistically significant. If the CI crosses the null value, then there is no statistically significant difference b/w the groups.
How do you diagnose Schizoaffective d/o?
Psychosis must occur in the absence of major mood episodes, but mood ssx must be present for most of the illness. There is a lifetime history of 2+ weeks of psychotic ssx w/o mood disturbance.
How do you define True negatives? False positives?
>TN = (Spec) x (#patients w/o dse). >FP = (1 - Spec) x (#pts w/o dse).
Explain Type 2 (Beta) error.
Type 2 (beta) error is related to how much power a study has to detect a difference when a difference ACTUALLY exists (Power = 1 - beta). A larger sample size denotes greater power.
What is the most common initial finding for a patient going through Alcohol withdrawal?
At 6-24 hrs since the last drink, a patient may experience Tremors (MC) as well as anxiety, insomnia, GI upset, and palpitations.
