Table 1.

AGO grades of recommendation

+ +	This investigation or therapeutic intervention is highly beneficial for patients, can be recommended without restriction, and should be performed.
+	This investigation or therapeutic intervention is of limited benefit for patients and can be performed.
+/−	This investigation or therapeutic intervention has not shown benefit for patients and may be performed only in individual cases. According to current knowledge, a general recommendation cannot be given.
−	This investigation or therapeutic intervention can be of disadvantage for patients and might not be performed.
−/−	This investigation or therapeutic intervention is of clear disadvantage for patients and should be avoided or omitted in any case.