. 2018 Apr 26;18:143. doi: 10.1186/s12887-018-1093-z

Table 1.

Case-control studies included in the research

Author	Sample	country	Exposure categorization method	Age group (year)	Asthma Diagnosis	Publication year	Time duration	Quality Score
Gennuso & et al. [48]	Case:85	(USA)	Reference data Normal <85, Obese: ≥ 85^th <95^th.Very obese: ≥ 95^th [15]	Case: 4-16	Physician diagnosed asthma	1998	N/R	80
Gennuso & et al. [48]	Control:86	(USA)		Control:4-16	Physician diagnosed asthma	1998	N/R	80
Vignolo & et al. [49]	Case:554	(Italy)	BMI- (SDS) units (z-score)	Case: 2.2-16.1	Physician diagnosed asthma	2005	Case: January –December 2001	80
Vignolo & et al. [49]	Control:625	(Italy)	BMI- (SDS) units (z-score)	Control: 2.4–16.3	Physician diagnosed asthma	2005	Control: April-May 2001	80
Mansell & et al. [50]	Case:134	(USA)	Overweight >85^th and non overweight <85^th (CDC growth charts)	Case: 12-18	Physician diagnosed asthma	2006	N/R	80
Mansell & et al. [50]	Control:82	(USA)		Control:12-18	Physician diagnosed asthma	2006	N/R	80
Vargas & et al. [51]	Case:213	(USA)	Risk for overweight ≥ 85^th-<95^th/ overweight ≥ 95^th (CDC growth charts )	Case: 3-5	Physician diagnosed asthma	2007	November 2000-December 2003	90
Vargas & et al. [51]	Control:816	(USA)		Control:3-5	Physician diagnosed asthma	2007	November 2000-December 2003	90
Careneiro bertolace & et al. [52]	Case:231	(Brazil)	Overweight :≥ 85^th and Obese: ≥ 95^th (CDC growth charts)	Case: 13-14	Completed ISAAC questionnaire by adolescence	2008	March-December 2005	80
Careneiro bertolace & et al. [52]	Control:190	(Brazil)	Overweight :≥ 85^th and Obese: ≥ 95^th (CDC growth charts)	Control:13-14	Completed ISAAC questionnaire by adolescence	2008	March-December 2005	80
Henkin & et al. [40]	Case:94	(USA) (Asian patient)	Underweight<20%, normal 20-85%, risk for overweight 85-95% & Overweight >95% (CDC growth charts	Case: 4-18	Physician-diagnosed asthma	2008	N/R	100
Henkin & et al. [40]	Control:94	(USA) (Asian patient)		Control:4-18	Physician-diagnosed asthma	2008	N/R	100
Walders-Abramson & et al. [53]	Case:59	(USA)	≥95^th obese,” 85^th–95^th “overweight,”15 and <85^th “normal weight (CDC growth charts)	Case: 10-16	Physician-diagnosed asthma	2009	December 2005-July 2007	80
Walders-Abramson & et al. [53]	Control:59	(USA)		Control:10-16	Physician-diagnosed asthma	2009	December 2005-July 2007	80
Tsai & et al. [54]	Case:27	(USA)	Age- and sex-specific cut-off points for childhood by (IOTF)	Case: 9-11	Parent reported according physician-diagnosed asthma and meds use	2012	2004-2006	80
Tsai & et al. [54]	Control:27	(USA)		Control:9-11		2012	2004-2006	80
Ahmadi-afshar & et al. [55]	Case:200	(Iran)	Overweight : BMI>85^th and Obese BMI>95^th (CDC growth charts)	Case: 6-15	Physician-diagnosed asthma	2013	March-September 2010	80
Ahmadi-afshar & et al. [55]	Control:200	(Iran)		Control:6-15	Physician-diagnosed asthma	2013	March-September 2010	80
Scepanovic & et al. [16]	Case:354	(Montenegro)	Based on the BMI percentile values	Case: 6-15	Physician-diagnosed asthma	2013	N/R	70
Scepanovic & et al. [16]	Control:354	(Montenegro)	Based on the BMI percentile values	Control: 6-15	Physician-diagnosed asthma	2013	N/R	70
Nahhas & et al. [43]	Case:632	(Saudi Arabia)	Underweight <5^th, Normal 5^th-85^th, Overweight 85^th-94^th & obese ≥ 95 (CDC growth charts)	Case: 6-8	Complete a ISAAC questionnaire by parent	2014	N/R	90
Nahhas & et al. [43]	Control:632	(Saudi Arabia)		Control: 6-8	Complete a ISAAC questionnaire by parent	2014	N/R	90
Forno & et al. [42]	Case:351	(Puerto Rico)	BMI z scores based on CDC growth charts	Case: 6-14	Physician-diagnosed asthma	2014	March 2009 -June 2010	90
Forno & et al. [42]	Control:327	(Puerto Rico)	BMI z scores based on CDC growth charts	Control: 6-14	Physician-diagnosed asthma	2014	March 2009 -June 2010	90
Papoutsakis & et al. [41]	Case:217	(Greece )	Age- and sex-specific cut-off points for childhood by (IOTF)	Case: 5-11	Physician-diagnosed asthma	2015	November 2007-September 2010	90
Papoutsakis & et al. [41]	Control:297	(Greece )		Control: 5-11	Physician-diagnosed asthma	2015	November 2007-September 2010	90
Rice & et al. [56]	Case:287	(Peru)	Age- and sex-specific cut-off points for childhood by (IOTF)	Case: 9-19	Physician-diagnosed asthma	2015	N/R	80
Rice & et al. [56]	Control:96	(Peru)		Control: 9-19	Physician-diagnosed asthma	2015	N/R	80
Groth & et al. [57]	Case:61	(USA)	Underweight <5^th, Normal ≥ 5^th and < 85^th, Overweight ≥ 85^th and < 95^th obese ≥ 95^th (CDC growth charts)	Case: 12-15	Physician-diagnosed asthma	2016	2002-2004	90
Groth & et al. [57]	Control:484	(USA)		Control: 12-15	Physician-diagnosed asthma	2016	2002-2004	90
Lawson& et al. [44]	Case:78	(Canada)	Age- and sex-specific cut-off points for childhood by (IOTF)	Case: 6-14	Physician-diagnosed asthma	2017	2011	100
Lawson& et al. [44]	Control:451	(Canada)		Control: 6-14	Physician-diagnosed asthma	2017	2011	100

N/R Not reported