21
Strength of Action Terms in Guideline Statements and
Implied Levels of Obligation
Strength Definition Implied Obligation
Strong
Recommendation
(S)
A strong recommendation means
that the benefits of the recommended
approach clearly exceed the harms
(or that the harms clearly exceed
the benefits, in the case of a strong
negative recommendation) and that
the quality of the supporting evidence
is excellent (grade A or B). In some
clearly identified circumstances, strong
recommendations may be made on
the basis of lesser evidence, when
high-quality evidence is impossible
to obtain and the anticipated benefits
strongly outweigh the harms.
Clinicians should follow
a strong recommendation
unless a clear and
compelling rationale for
an alternative approach is
present.
Recommendation
(R)
A recommendation means that the
benefits exceed the harms (or that
the harms exceed the benefits, in the
case of a negative recommendation)
but that the quality of evidence is
not as strong (grade B or C). In some
clearly identified circumstances,
recommendations may be based on
lesser evidence when high-quality
evidence is impossible to obtain and
the anticipated benefits outweigh the
harms.
Clinicians should
also generally follow a
recommendation but
should remain alert to
new information and
sensitive to patient
preferences.
Option
(O)
An option means that either the
quality of evidence is suspect (grade
D) or that well-done studies (grade A,
B, or C) show little clear advantage to
one approach versus another.
Clinicians should be
flexible in their decision
making regarding
appropriate practice,
although they may set
bounds on alternatives.
Patient preference
should have a substantial
influencing role.