13 terms

Tutorial 11 (Final Review)


Terms in this set (...)

Age-Period-Cohort effect
1. period
a. regardless of age/cohort, change in rate in particular period
2. cohort
a. regardless of age/period, shift in peak of rate according to cohort
3. age
a. regardless of cohort/period, shift in peak of rate according to age
Survival analysis
1. actuarial
a. interval based on regular periods
b. censored handled by contributing 50%
2. survival
a. intervals based on event occurences
b. censored events in contribute to period they werent censored, ignored/removed from susceptible persons moving forward
point prevalence
1. ALL cases / total pop
Cumulative incidence
1. total # events occurred during period of interest / susceptible population
2. can be same in treatment arms
Incidence rate
1. # events occurred / person time of susceptible persons
2. can be different in treatment arms
1. select based on outcome then look for E
2. when OR approx. RR
a. rare disease assumption
b. CCoh b/c rep. general pop
Research question
P = who subject, what problem being addressed
I/E = what is intervention/E
C = Comparison group
O = outcome of interest
1. marginal probability = prob event occurring
a. Pr (E) = a+b/N
2. Joint Prob = prob two events occuring (E and O)
a. Pr(E+O) = A / N
3. conditional prob = prov one event give another ahs occurred
a. Pr(O l E) = A / (A+B)

4. Interchangeability
a. when conditional prob not same as marginal prob, events NOT INDEPENDENT
b. when marg. prob. independent, groups interchangeable
drawing up DAGs and causal pathways
1. include direction of arrows
2. pathways
a. E ->O
B. E <-AGE->O
D. E <-GEND.->AGE->O

a = main causal pathway
b to F = non causal pathways
b to E = unblocked (open)
F = blocked

control for Age
measurement biases
1. sens and spec interpreted as how well we avoid misclass bias in study
2. ND masclass biases towrad null
e. D misclass can go in either direction
general types of measurement bias
1. selection
a. berksonian
b. immortal time/ survival
c. lead time/length
d. over-diagnosis
e. compensating
2. info
a. recall
b. interviewer
c. observer
d. respondent
3. border line
a. medical surveillance
b. incidence/prevalence
c. temporal
1. factor differs b/t E and NE that explains some to all of measure of effect identified
2. degree of distortion can be measrued by exces risk b/t crude and adjusted measures
3. OR, IR, rate difference: adjusted might no average out to crude as they do for RR
a. non-collapsibility, crude not weighted averages of adjusted
Exam tips
1. state assumptions
2. describe in as many ways as possible (additive, quantitative, EM)
3. anticipate shortcomings and remedies or explanations for decisions (sampling strategies and why chose to recruit from a particular sample)