Table 3.

Quality of available evidence

Study	Risk of bias	Inconsistency	Indirectness	Imprecision	Others	No of patients Probiotic control	Effect	Quality
Ice cream	Serious	Not serious	Not serious	Serious	None	107 107	No difference	Moderate
Yogurt	Serious	Not serious	Not serious	Serious	None	241 238	Difference present	Moderate
Tablet	Serious	No serious	Not serious	Serious	None	32 64	No difference	Moderate
Lozenges	Serious	Not serious	Not serious	Serious	None	127 111	No difference	Moderate
Chewing gum	Serious	Not serious	Not serious	Serious	None	17 19	No difference	Moderate
Capsule	Serious	Not serious	Not serious	Serious	None	30 29	No difference	Moderate
Drop	Serious	Not serious	Not serious	Serious	None	30 23	No difference	Moderate