Behavioural Sciences Flashcards
What is a cross sectional study? What can it be used to measure?
Assesses frequence of disease (or other factors) in a group of people at a particular point in time - What is happening?
Measures disease prevalence - shows risk factor association with disease NOTE correlation =/= causation
What is a case control study? What does it measure?
Compares group with disease to control - Looks for risk factor
Measures Odds ratio
What is a cohort study? What does it measure?
Compares group with risk factor to group without risk factor. Looks to see if exposure increases likelihood of disease. Can be retrospective or prospective.
Measure relative risk - e.g. smokers had higher risk of developing COPD than non smokers.
What is a twin concordance study? What does it measure?
Compares the frequency with which both monozygotic twins or both dizyogtic twins develop the same disease;
Measures nature vs nurture
What is an adoption study? What does it measure?
Compares siblings raised by biological vs adoptive parents
Measures nature vs nurture
What does a triple blinded clinical trial entail?
Blinding of patients, doctors and researchers analyzing the data
What is the purpose of a phase I clinical trial?
Assesses safety, toxicity, pharmacokinetics and pharmacodynamics
What is the purpose of the phase 2 clinical trial?
Assesses treatment efficacy, optimal dosing and adverse effects
What is the purpose of phase 3 clinical trials?
Compares new treatment to current treatment or placebo
What is the purpose of phase 4 clinical trials? what does it involve?
Postmarketing surveillance of patients after treatment is approved.
Detects rare or long term adverse efects
Define the sensitivity of a test.
Probability that a test detets a disease when disease is present.
SN-N-OUT = a highly SeNsitive test, when Negative, rules OUT disease
Define the specificity of a test
Probability that the test detects no disease when disease is absent.
SP-P-IN = a highly SPecific test, when Positive, rules IN disease
Define positive predictive value
Probability that a person actually has the disease when given a positive test result
Define negative predictive value
Probability that person actually is disease free when given a negative test result
Define incidence and prevalence
Incidence - no of new cases / no of people
Pevalnce = no of existing cases / no of people at risk
Define odds ratio
Odds tht the group with the disease was exposed to a risk factor divided by odds that the group without the disease was exposed
Define the relative risk
Risk of developing disease in exposed group divided by risk in unexposed group
Define the attributable risk
difference in risk between exposed and unexposed groups
Define relative risk reduction
Proportion of risk reduction attributable to the intervention as compared to a control
RRR = 1 - Relative Risk
Define absolute risk reduction
Difference in risk attributable to the intervention as compared to a control
ARR = (c/c+d) - (a/a+b)
Define the number needed to treat
Number of patients who need to be treated for 1 patient to benefit
Define the number needed to harm
number of patients who need to be exposed to a risk factor for 1 patient to be harmed
Define precision of a test
absence of random variation in test
Define the accuracy of a test
Trueness of test measurements
What is the berkson bias?
Study population selected from hospital is less healthy than general population
What is the healthy worker effect?
Study population is more healthy than general population
What is the non response bias?
participating subjects differ from nonrespondents in meaningful ways
How would you reduce selection bias?
Randomization
Ensure the choice of the right comparison group
How would you reduce recall bias?
Decrease time from exposure to follow up
What is measurement bias and how would you reduce it?
Info is gathered in a way that distorts it
Reduced using a standardised method of data collection
What is procedure bias and how would you reduce it?
Subjects in different groups are not treated the same
Reduce - Blinding and use of placebo to reduce influence of participants and researchers
What is observer-expectancy bias and how would it be reduced?
Researcher’s belief in the efficacy of a treatment changes the outcome of that treatment - self fulfilling prophecy
Reduce by blinding and use of placebo to reduce influence of participants and researchers
What is a confounding bias? How would it be reduced?
When a factor is related to both exposure and outcome but isnt on the causal pathway
Reduced by multiple studies, crossover studies where the subjects act as their own controls (they receive both treatments although the order in which they receive them are randomised), and matching (patients with similar characteristics in both treatment and control groups)
What is lead time bias and how would you reduce it?
Early detection is confused with increased survival
Reduced by measuring back end surbvival (adjust survival rate according to the severity of disease at time of diagnosis)
Define standard error
an estimate of how much variability exists between sample mean and true population mean
What is bimodal distribution?
2 peaks of distribution, suggesting 2 different populations
What is positive and negative skew distribution?
Positive - Asymmetry with longer tail on right due to mean > median > mode
Negative - asymmetry with longer tail on left due to mean < median < mode
What is the null hypothesis?
no relationship between factor and outcome
What is the alternative hypothesis?
Some relationship between factor and outcome
What would occur if the study result indicated the null hypothesis was correct and the reality is that the null hypothesis is correct?
Correct result - there is no relationship
What would occur if the study results indicated the alternative hypothesis was correct but the reality was that the null hypothesis was correct?
Type 1 error (α) - False positive error.
α is probability of making a type I error. α = you sαw a difference that did not exist
Wha twould occur if the study results indicated the null hypothesis was correct but th ereality was that the alternative hypothesis was correct? How would you reduce this error?
Type II error (ß) - False negative error
ß is probability of making a type II error.
Reduced by increasing sample size, precision of measurement
When would you accept the null hypothesis in:
a) mean difference
b) odds ratio and relative risk
c) CIs between 2 groups
a) H0 not rejected when CI for a mean difference between 2 variables includes 0
b) odds ratio or relative risk includes 1
c) if CIs between 2 groups overlaps = H0 accepted
What is the t-test used for?
checks difference between mean of 2 groups
Tea is meant for 2
What is ANOVA used for?
checks differences between means of 3 or more groups
What is Chi-square used for
checks differences between 2 or more percentages or proportions of categorical outcomes (not mean values) e.g. chi square used to measure PERCENTAGE of MEMBERS of 2 different ethnic groups rather than comparing the MABP between 2 different ethnic groups
What is the pearson correlation coefficient?
“Can I draw a line graph to represent the data?” - r is between -1 and +1
Closer to 1 is stronger linear correlation. +1 is positive correlation. -1 is negative correlation. 0 is no correlation.
What is primary, secondary, tertiary and quaternary disease prevention?
Primary - Prevent disease occurrence e.g. vaccine
Secondary - Screening early for diseaes
Tertiary - Treatment to reduce disability from disease
Quaternary - Identify patients at risk of unnecessary treatment
Who is medicare for?
medicare for >65, <65 with disabilities and those with end stage renal disease
Who is medicaid for?
Medicaid for people with v low incomes
What are the 4 parts of medicare?
Part A - Hospital insurance
Part B - Basic medical bills
Part C - Parts a and b delivered by approved private companies
Part D - Prescription drugs
What is the concept of autonomy?
respect patients as individuals to create conditions necessary to make self informed decisions and to honour their decisions
What is the concept of beneficence?
duty to act in the patient’s best interest.
What is the concept of Justice?
Treat the patients fairly and EQUITABLY. Not necessary equally
What does informed consent require?
- Disclosure of info about disease and treatment
- Ability to understand
- Ability to make ones own decisions
- Freedom from coercion or manipulation
What situations do not require parental consent?
- Sex (contraception, STIs, pregnancy)
- Drugs (addiction)
- Rock and roll (emergency/trauma)
What are advance directives?
Instructions given by a patient in anticipation of the need for a medical decision
What is an oral advancce directive?
Incapacitated patient’s prior oral statements commonly used as a guide
What is a living will?
Describes treatments the patient wishes to recieve or not recieve if they lose decision making capacity
What is a medical power of attorney?
Patient designates an agent to make medical decisions in the event that they lose decision making capacity
What is a surrogate decision maker
If patient loses capcity and has not prepared an advance directive, surrogates who knew the patient must determine what the patient would have done
spouse > adult children > parents > adult siblings > others
What is an Apgar score? What do the scores mean?
Appearance, Pulse, Grimace, Activity, Respiration
Assessment of newborn vital signs following labour via a 10 point scale evaluated at 1 minute and 5 minutes.
>7 is good, 4-6 = assist and stimulate, <4 = resus
Define low birth weight. What are the risks?
<2500g.
risks of sudden infant death syndrome and mortality
What are the motor milestones of a 0-12 month baby?
- Primitive reflexes disappear
- Posture - lifts head up prone (1mo) –> rolls and sits (by 6 mo) –> crawls (by 8 mo) –> stands up (by 10 mo) –> walks (12-18 months)
- Picks - passes toys hand to hand (by 6 mo), Pincer grasp (by 10)
- Points to objects (by 12 mo)
Parents Start Observing
Child Rearing Working
Dont Forget, theyre still Learning!
What are the social milestones of a 0-12 mo baby?
- Social smile (by 2 mo)
- Stranger anxiety (by 6 mo)
- Separation anxiety (by 9 mo)
Parents Start Observing
Child Rearing Working
Dont Forget, theyre still Learning!
What are the verbal/cognitive milestones of a 0-12 mo baby?
- Orients - first to voice (by 4 mo), then to name and gestures (by 9 mo)
- Object peramnence (by 9 mo)
- Oratory - says mama and dada (by 10 mo)
Parents Start Observing
Child Rearing Working
Dont Forget, theyre still Learning!
What are the motor milestones of a 12-36 mo baby?
- Cruises - takes first steps (by 12mo)
- Climbs stairs (by 18 mo)
- Cubes stacked - number = age (yr) x 3
- Cultured - feeds self with fork and spoon (by 20 mo)
- Kicks ball (by 24 mo)
Parents Start Observing
Child Rearing Working
Dont Forget, theyre still Learning!
What are the social milestones of a 12-36 mo toddler?
- Recreation - parallel play (play next to each other but independently)
- Rapprochement - moves away from and returns to mother (by 24 mo)
- Realisation - core gender identitiy formed (by 36 mo)
Parents Start Observing
Child Rearing Working
Dont Forget, theyre still Learning!
What are the verbal/cognitive milestones of a 12-36 mo toddler?
- Words - 200 words by age 2, 2 word sentences
Parents Start Observing
Child Rearing Working
Dont Forget, theyre still Learning!
What are the motor milestones of a 3-5 yr old?
- Drive - tricycle (3 wheels at yr 3)
- Drawings - copies line or circle, stick figure (by yr 4)
- Dexterity - hops on one foot (by yr 4), uses buttons or zippers and grooms self (by yr 5)
Parents Start Observing
Child Rearing Working
Dont Forget, theyre still Learning!
What are the social milestones of a 3-5 yr old?
- Freedom - comfortably spends part of day away from mother (by 3 yr)
- Friends - coop play, has imaginary friends (by 4 yr)
Parents Start Observing
Child Rearing Working
Dont Forget, theyre still Learning!
What are the verbal/cognitive milestones of a 3-5 yr old?
Language - 1000 words by age 3 (3 zeroes), uses complete sentences (by yr 4)
Legends - can tell detailed stories (by yr 4)
Parents Start Observing
Child Rearing Working
Dont Forget, theyre still Learning!
What sexual changes occur in elderly men?
Slower erection / ejaculation
Longer refractory period
Sexual interst does not decrease
What sexual changes occur in elderly women?
Vaginal shortening, thinning, dryness
Sexual interest does not decrease
What is presbycusis?
Sensorinerual hearing loss due to destruction of hair cells at cochlear base
What is the no. 1 cause of death in:
a) <1
b) 1-14 yo
c) 15 - 34 yo
d) 35-44 yo
e) 45-64 yo
f) 65+
a) congenital malformations
b) accidents
c) accidents
d) accidents
e) cancer
f) heart disease
What is the no. 2 cause of death in:
a) <1
b) 1-14 yo
c) 15 - 34 yo
d) 35-44 yo
e) 45-64 yo
f) 65+
a) preterm birth
b) cancer
c) suicide
d) cancer
e) heart disease
f) cancer
What is the no. 3 cause of death in:
a) <1
b) 1-14 yo
c) 15 - 34 yo
d) 35-44 yo
e) 45-64 yo
f) 65+
a) SIDS
b) congenital malformations
c) homicide
d) heart disease
e) accidents
f) chronic resp disease
