BACKGROUND: Although the effectiveness of allergen monotherapy immunotherapy for allergic rhinitis (AR) has been well established by many prior studies, other aspects of immunotherapy are still incompletely documented by high-quality studies. The many published papers describe various results. The aim of the present study was to conduct a meta-analysis on the effectiveness of allergen immunotherapy. METHODS: A total of 56 homogeneous studies were included in the analysis. The inclusion criteria used to select articles were as follows: (1) placebo-controlled clinical trials; (2) the use of immunotherapy; (3) participants and/or physicians were or were not blinded to immunotherapy or placebo assignment (single-blinding, double-blinding, or no-blinding studies); and (4) randomization or not of those in the immunotherapy and placebo groups. RESULTS: Between 2003 and 2013, 114 placebo-controlled clinical trials were reported in Medline. Studies describing recovery rates in immunotherapy and placebo groups numbered 56. The distribution of such works was homogeneous (heterogeneity chi-square = 16.11; degrees of freedom [df] = 55; p = 1.000). The extent of recovery in immunotherapy groups was 53.671-fold greater than in placebo groups (Mantel-Haenszel [M-H] pooled risk ratio [RR] = 53.671; 95% confidence interval [CI], 36.981 to 77.893; z = 20.96; p < 0.001). CONCLUSION: Our meta-analysis suggests that immunotherapy is associated with a recovery rate 53.671-fold that of placebo.
BACKGROUND: Although the effectiveness of allergen monotherapy immunotherapy for allergic rhinitis (AR) has been well established by many prior studies, other aspects of immunotherapy are still incompletely documented by high-quality studies. The many published papers describe various results. The aim of the present study was to conduct a meta-analysis on the effectiveness of allergen immunotherapy. METHODS: A total of 56 homogeneous studies were included in the analysis. The inclusion criteria used to select articles were as follows: (1) placebo-controlled clinical trials; (2) the use of immunotherapy; (3) participants and/or physicians were or were not blinded to immunotherapy or placebo assignment (single-blinding, double-blinding, or no-blinding studies); and (4) randomization or not of those in the immunotherapy and placebo groups. RESULTS: Between 2003 and 2013, 114 placebo-controlled clinical trials were reported in Medline. Studies describing recovery rates in immunotherapy and placebo groups numbered 56. The distribution of such works was homogeneous (heterogeneity chi-square = 16.11; degrees of freedom [df] = 55; p = 1.000). The extent of recovery in immunotherapy groups was 53.671-fold greater than in placebo groups (Mantel-Haenszel [M-H] pooled risk ratio [RR] = 53.671; 95% confidence interval [CI], 36.981 to 77.893; z = 20.96; p < 0.001). CONCLUSION: Our meta-analysis suggests that immunotherapy is associated with a recovery rate 53.671-fold that of placebo.