15
1.
Establish initial
level of confidence
Study Design Initial
confidence
in an
estimate
of effect
Randomized
trials ª
High
confidence
Observational
studies ª
Low
confidence
2.
Consider lowering or raising
level of confidence
Reasons for considering
lowering or raising confidence
$ Lower if # Higher if
Risk of Bias
Inconsistency
Indirectness
Imprecision
Publication
bias
Large effect
Dose response
All plausible
confounding
& bias
• would reduce a
demonstrated
effect, or
• would suggest
a spurious
effect if no
effect was
observed
3.
Final level of
confidence
rating
Confidence
in an estimate
of effect
across those
considerations
H = High
M = Moderate
L = Low
VL = Very Low
1.
Rating
the
quality
of
the
evidence
2.
Determinants
of
the
strength
of
recommendation
Quality
(certainty)
of evidence
Balance
between
benefits, harm
& burden
Patients'
values &
preferences
Resources
and cost
W
=
Weak
/
C
=
Conditional
S
=
Strong
3.
Implication
of
the
strength
of
recommendation
• Population: Most people in
this situation would want the
recommended course of action and
only a small proportion would not
• Health care workers: Most people
should receive the recommended
course of action
• Policy makers: The recommendation
can be adapted as a policy in most
situations
• Population: The majority of people
in this situation would want the
recommended course of action, but
many would not
• Health care workers: Be prepared to
help people to make a decision that
is consistent with their own values/
decsion aids and shared decision
making
• Policy makers: There is a need for
substantial debate and involvement
of stakeholders
Recommendation Grading
Certainty that the desirable
consequences exceed the
undesirable consequences after
considering all of the following: