Table 2 Characteristics of Excluded Studies
Study | Reason for Exclusion |
|---|---|
Trapp 1993[20] | Group 1 and 2 randomized and double-blinded, but group 3 were those did not want to eat yogurt |
Helin 2002[21] | Patients had birch pollen allergy and mainly rhino-conjunctivitis |
Xiao 2007[22] | Investigates symptoms induced by Japanese cedar pollen in an environmental exposure unit |
Ishida 2005[23] | Randomized single-blind study with quality score = 0 |