Characteristics of included studies.

<p>Injection number, number of injection in build-up phase; Total duration, total treatment duration; I, Investigated group; C, Control group; NSS, Nasal symptom score; MS, Medicine scores; CT, cutaneous test; S, safety; TNC, Titrated nasal challenge; HRQL, health-related quality of life; Der p, Dermatophagoides pteronyssinus; Sal k, Salsola kali; D.G and T.P, D. Glomerata and T. Paniceum.</p

Flowchart of studies included.

<p>RCT, randomized controlled trial.</p

Cluster Subcutaneous Allergen Specific Immunotherapy for the Treatment of Allergic Rhinitis: A Systematic Review and Meta-Analysis

<div><p>Background</p><p>Although allergen specific immunotherapy (SIT) represents the only immune- modifying and curative option available for patients with allergic rhinitis (AR), the optimal schedule for specific subcutaneous immunotherapy (SCIT) is still unknown. The objective of this study is to systematically assess the efficacy and safety of cluster SCIT for patients with AR.</p><p>Methods</p><p>By searching PubMed, EMBASE and the Cochrane clinical trials database from 1980 through May 10th, 2013, we collected and analyzed the randomized controlled trials (RCTs) of cluster SCIT to assess its efficacy and safety.</p><p>Results</p><p>Eight trials involving 567 participants were included in this systematic review. Our meta-analysis showed that cluster SCIT have similar effect in reduction of both rhinitis symptoms and the requirement for anti-allergic medication compared with conventional SCIT, but when comparing cluster SCIT with placebo, no statistic significance were found in reduction of symptom scores or medication scores. Some caution is required in this interpretation as there was significant heterogeneity between studies. Data relating to Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) in 3 included studies were analyzed, which consistently point to the efficacy of cluster SCIT in improving quality of life compared to placebo. To assess the safety of cluster SCIT, meta-analysis showed that no differences existed in the incidence of either local adverse reaction or systemic adverse reaction between the cluster group and control group.</p><p>Conclusion</p><p>Based on the current limited evidence, we still could not conclude affirmatively that cluster SCIT was a safe and efficacious option for the treatment of AR patients. Further large-scale, well-designed RCTs on this topic are still needed.</p></div

Adverse events.

<p>NA, Not available data; LRNT, Local reaction not requiring treatment; LRT, Local reaction requiring treatment;</p><p>ESRG1, Early systemic reaction grade 1(<30 minutes); ESRG2, Early systemic reaction grade 2(<30 minutes);</p><p>LSR, Late systemic reaction (>30 minutes); LR, Local reaction; SR, Systemic reaction; I,Investigated group; C,Control group.</p