The complexity of using SIT and interpreting its efficacy
The presence of publication bias also introduces an element of statistical heterogeneity into these meta-analyses. These limitations suggest a cautious interpretation of results when extending to all patient populations, allergens, and AR vs asthma.
| Study/Year | Patients | Allergens | Symptom Scores, SMD (95% CI) | Medication Scores, SMD (95% CI) | Comment |
| Calderon | 2,871 adults | SCIT | -0.73 (-0.97, -0.50) | -0.57 (-0.82, -0.33) | No children included |
| 2007 | Seasonal | I2= 63% | I2= 64% | No fatalities reported Moderate heterogeneity | |
| 4,589 adults and | SLIT | -0.49 (-0.64, -0.34) | -0.32 (-0.43, 0.21) | Considerable heterogeneity | |
| 2010 | children | Seasonal and perennial | I2= 81% | I2= 50% | despite inclusion of large trials |
| 2006 | 484 children | SLITSeasonal and perennial | -0.56 (-1.01, -0.10)I2= 81% | -0.76 (-1.46, -0.06) I2= 86% | Considerable heterogeneity |
| Olagrnbel and Alvarez Puebla 2005 | 232 children | SLITSeasonal and perennial | -0.44 (-1.22, -0.35) I2 = Not reported | Not reported | Small numbers Heterogeneity not reported |
| Compalati | 382 adults | SLIT | -0.95 (-1.77, -0.14) | -1.88 (-3.65, -0.12) | Considerable heterogeneity |
| 2009 | and children | House dust mite | I2= 92% | I2= 95% | despite focus on a single allergen |
| Di Bona | 2,971 adults and | SLIT | -0.32 (-0.44, -0.21) | -0.33 (-0.50, -0.16) | Moderate heterogeneity |
| 2010 | children with rhinitis | Grass pollen | I2= 56% | I2= 78% |
See Table 1 and 3 legends for expansion of other abbreviations. (Reproduced with permission from Calderon)
The complexity of using SIT and interpreting its efficacy is particularly evident with the concept of single vs multiallergen extract use. In the United States, allergists favor using multiallergen extracts, with the hope of addressing all major sensitivities, whereas allergists in Europe recommend against this practice Avanafil Canada, citing the rationale that inclusion of multiple allergens could potentially lead to a dilution effect, such that an effective dose is not given and also that proteolytic action of one extract on another might lead to its degradation.