Summary - Introduction to PharmacoEconomics (WBFA047-05)

EPIDEMIOLOGICAL MEASUREMENTS
Infidence &
P
revalence > Odds ratio >
- for case-control !




S S measures association between exposure

cases
>
-
for case-control



onthaastation
new


=




↑
·
or


over time
·
if OR = 1 >
-
exposure does not affect odds of outcome

period
if ORL1 exposure associated with higher
>
- odds


·
Prevalence = Static measure if OR < 1- > exposure associated with lower odds

↳
always per 1000 etc.


·
Incidence =
dynamic measure
>
QALY =

Quality Adjusted
-
Life Years
new cases
-

Cumulative
·
=
incidence total cases lived
number of
years utility weight
= x

cases
-new


·incidencerate(m)S
total persone e
=




>
Measures of risk >
- for conort !


1 Dynamic cohort :
changing composition probability that event will occur


Absolute a
group in
growing decreasing population risk events
=
·
·
or

# individuals in that
·
Cannot calculate cum .
Incidence :
group

Incidence Relative risk (RR)
Probabilityofeveniis
· ·
rate via approximation method =




+
-
LD =
I
robability of event in

stawcases end)/2)
a

Persons
un exposed population
ons time C/(c + a)



Risk difference (RD) risk (untreated) (treated
· = -


risk

↳ also : absolute risk
reduction CARR)

=
·
Number needed to treat =
RD

(NNT)




· No association when : RR =
1 or RD = 0

, STUDY BESIGN
Case-control >
Cross-sectional Study
>
study
&
analytical >
etiology
-




Determines potential risk factors in Observes of people at one point in time
a
group
& Relation disease
individuals with condition between exposure -




↳ ↳
retrospective often survey
generally a


↳ ↳
information/Selection bias likely no follow-up time


u To what extend do HPV infections Up How tal are Dutch men and women at ?
agezo
increase the risk of cervical cancer ?

↳
Nested case-control from retrosp cohort
Ecologic Study
=
>
.




-Cohort study Observes variable
at least 7 at
group level

Measures disease within of individuals La Fe
group .
looking at association between
Smoking
over period of time and
lung cancer in different countries
u
·
Prospective cohort > -


longitudinal No information available about members !

4) to follow up on who received
people

treatment/were exposed to risk factors 1 Inception cohort =
First time users in experiment
·

Retrospective conort >
Study question
=

analytical or descriptive
↳ uses
past data -
quick cheap ,
↳ causal
↳
How




healinge
does
high blood pressure affect heart


descriptive/analytical
·

with medicaten e

~
Randomized Control Trial (RCT)

Examines effectiveness of intervention

↳
experimental or control
group
↳ double blinded is ideal >
Study domain =
theoretical population where the

up
for cause-and-effect relationships related
finding are to


↳
in what extend is the ·
new
drug A better Free of determinant , time , and place
!


than the Standard treatment for medica ·
fe .

pregnant woman


condition X ? were exposures
the
assigned by
investigator ?
~
- - choose cohort instead of case -
control if start
No




Experts
J

Observational from exposure
study
?
Hypothesis testing ·
conort index reference
group
: -

- -
- -
No
yes No
↓ ↓
beste ↓
non-randomized
design
↓



Analytic
als
v



Descripti
een exposed non-exposed
↓

based
Sampling on



-
Neither



ExposureoutcomeT
↳
Statistically significant when 1 not in C
- d ↓
rol cross-sectional

study
>
When wide
range C- > not precise