Table 1: Characteristics of the included reviews
Condition; authorSearch dateCountryNo. of included studiesIncluded designPopulation
(adult or children)
DurationIndicationImmunotherapy evaluatedType of analysisIncluded allergensAMSTAR score*
Allergic asthma
Liao et al.,16 2015February 2014China11RCTChildren4 mo-3 yrAASLITMeta-analysisHouse dust mite7
Normansell et al.,17 2015March 2015UK52RCTMixed1 d-3 yrAA ± ARSLITMeta-analysisHouse dust mite, grass pollen, birch pollen, cockroach, cat, AlternariaParietariaArtemisia, olive pollen11
Lu et al.,18 2015February 2013China19RCTMixed4 mo-3 yrAASCITMeta-analysisHouse dust mite7
Tao et al.,19 2014March 2012China16RCTMixed10 wk- 25 moAA ± AR ± conjunctivitisSLITMeta-analysisHouse dust mite, grass, birch pollen6
Abramson et al.,1 2010August 2005Australia88RCTMixed 3 yrAASCITMeta-analysisHouse dust mite, pollen, animal dander, mould, latex7
Allergic rhinitis
Yang et al.,20 2016April 2016China4RCTMixed7-20 moARSLITMeta-analysisCedar pollen7
Di Bona et al.,21 2015April 2014Italy13RCTMixed12 wk-1 yrAR ± AASLITMeta-analysisGrass pollen8
Seidman et al.,3 2015November 2013US267CPG, SR, RCTMixedNRSeasonal and perennial ARSCIT, SLITNarrativeNR0
CADTH,22 2014June 2014Canada8RCTMixed9 wk-2 yrSeasonal AR ± conjunctivitisSCIT, SLITNetwork meta-analysisGrass pollen7
Feng et al.,23 2014May 2013China9RCTMixed2.3 mo-3 yrARSCIT (cluster)Meta-analysisGrass pollen, cat hair8
Devillier et al.,24 20142013; mo NRFrance28†RCTMixedNRSeasonal ARSLITMeta-analysisGrass pollen5
Dranitsaris et al.,25 2014December 2012Canada20RCTMixed1-34 moSeasonal ARSCIT, SLITMeta-regressionGrass pollen3
Larenas-Linnemann et al.,26 2013December 2012Mexico28RCT, NRSChildren,  adolescents6 mo-3 yrAR or RC ± AASLITNarrativeGrass or tree pollen, house dust mite, Alternaria, peanut, milk6
Lin et al.,27 2013 (Kim et al., 2013, Erekosima et al., 2014, Lin et al., 2013, Chelladurai et al., 2013)May 2012US142‡RCTMixedNRAllergic RC ± AASCIT, SLITNarrativePollen, cat, dog, cockroach, house dust mite11
Manzotti et al.,28 2013January 2012Italy7RCTMixed5.3-7 moSeasonal allergic RCSLITNarrativeGrass pollen1
Meadows et al.,29 2013 (Dretzke et al., 2013)April 2011UK28RCTMixedMean 3.6 yrAR ± AASCIT, SLITMeta-analysisGrass, tree or ragweed pollen, AlternariaParietaria10
Calderón et al.,6 2013March 2013UK44RCTMixed6-28 moAR and AASCIT, SLITNarrativeHouse dust mite3
Purkey et al.,30 2013December 2011US12RCTNR 5 yrSeasonal and perennial ARSCIT, SLITNarrativePollen3
Calderón et al.,31 2011January 2011UK42RCTMixed3-36 moSeasonal and perennial ARC or conjunctivitisSLITMeta-analysisPollen11
Larenas-Linnemann et al.,32 2011April 2011Mexico31§RCT, NRSChildren and adolescents3-36 moSeasonal or perennial AR or RC ± AASCITNarrativeHouse dust mite, grass pollen, birch, fungus5
Radulovic et al.,33 2010 (Wilson et al., 2009)August 2009UK
60RCTMixed2 wk-3 yr¶Seasonal and perennial ARSLITMeta-analysisParietaria, ragweed, tree pollen, house dust mite, cat10
Bousquet et al.,2 2011June 2009France94RCTMixedNRAR conjunctivitis, ± AASCIT, SLITNarrative
Grass pollen2
Calderón et al.,34 2010January 2009UK33RCTMixed1-84 moSeasonal ARCSCIT, SLITNarrativeGrass pollen1

Note: AA = allergic asthma, AR = allergic rhinitis, ARC = allergic rhinoconjunctivitis, CADTH = Canadian Agency for Drugs and Technologies in Health, CPG = clinical practice guideline, NR = not reported, NRS = nonrandomized study, RC = rhinoconjunctivitis, RCT = randomized controlled trial, SCIT = subcutaneous immunotherapy, SLIT = sublingual immunotherapy, SR = systematic review, UK = United Kingdom, US = United States.

*Maximum 11.

†Authors reported that 28 publications were included; unclear whether this represents the number of unique RCTs.

‡Authors reported that 142 articles were included; unclear whether this represents the number of unique RCTs.

§Authors reported that 31 articles were included; unclear whether this represents the number of unique RCTs.

¶Three consecutive grass pollen seasons.