sentence: 20 The Standard Mean Difference ( SMD ) for symptoms between active and placebo was here : − 2.03 ( − 1.89 to − 2.86 ) versus − 1.13 in the Abramson meta-analysis ; whereas the SMD on medication was : − 2.74 ( − 1.79 to − 3.69 ) versus − 0.51 in the Abramson review.20 Comparing with the above mentioned similar study , performed in the same hospital with allergen extracts of D. pteronyssinus and D. siboney , using the same standardized dosage schedule , current results with B. tropicalis seem to be also better , both in terms of SMD or relative values of symptom / medication score decrease as compared to placebo group.45 Concerning the respiratory function , the results on decreased PEF variability , although modest in size , are in agreement with primary clinical outcomes and with previous results with D. pteronyssinus and D. siboney .