Table 2.

Data sources and measures of outcomes in the studies included in the review.

Authors, year	Input data source	Input data format	Input features (independent variables)	Outcome data type	Outcome measures	Unit of analysis
Abdel-Aal and Mangoud [26], 1997	Medical survey data	Tabular	13 health parameters	Continuous	WHRa	Individual
Positano et al [71], 2008	MRIb	Image	Subcutaneous adipose tissue and visceral adipose tissue	Binary	Abdominal adipose tissue distribution	Individual
Ergün [70], 2009	Obtained from participants	Tabular	24 obesity parameters	Binary	Classification of obesity	Individual
Yang et al [69], 2009	Clinical data	Text	Clinical discharge summaries	Binary	Obesity status	Individual
Zhang et al [68], 2009	Objective measure	Tabular	Data recorded regarding the weight of the child during the first 2 years of the child’s life	Binary	Obesity	Individual
Heydari et al [67], 2012	Questionnaire and objective measure	Tabular	Age, systole, diastole, weight, height, BMI, WCc, HCd, and triceps skinfold and abdominal thicknesses	Binary	Obesity	Individual
Kupusinac et al [66], 2014	Objective measure	Tabular	Gender, age, and BMI	Continuous	BFPe	Individual
Shao [65], 2014	Objective measure	Tabular	13 body circumference measurements	Continuous	BFP	Individual
Chen et al [64], 2015	Objective measure	Tabular	18 blood indexes and 16 biochemical indexes	Continuous	Overweight	Individual
Dugan et al [63], 2015	Questionnaire and objective measure	Tabular	167 clinical data attributes	Continuous	Obesity	Individual
Nau et al [62], 2015	Two secondary data sources (InfoUSA and Dun & Bradstreet)	Tabular	44 community characteristics	Binary	Obesogenic and obesoprotective environments	Community
Almeida et al [61], 2016	Objective measure	Tabular	Age, sex, BMI z score, and calf circumference	Continuous	BFP	Individual
Lingren et al [60], 2016	EHRf	Tabular	EHR data	Binary	Obesity	Individual
Seyednasrollah et al [59], 2017	Objective measure	Tabular	Clinical factors and genetic risk factors	Binary	Obesity	Individual
Hinojosa et al [58], 2018	Objective measure	Tabular	School environment	Binary	Obesity	School
Maharana and Nsoesie [57], 2018	Objective measure	Image	Built environment	Continuous	Prevalence of obesity	Census tract
Wang et al [56], 2018	Objective measure	Tabular	Single-nucleotide polymorphisms	Binary	Obesity risk	Individual
Duran et al [55], 2018	NHANESg	Tabular	Age, height, weight, and WC	Binary	Excess body fat	Individual
Gerl et al [54], 2019	Objective measure	Tabular	Human plasma lipidomes	Binary and continuous	Obesity: BMI, WC, WHR, and BFP	Individual
Hammond et al [53], 2019	EHR and publicly available data	Tabular	EHR data	Binary and continuous	Obesity status	Individual
Hong et al [52], 2019	EHR	Text	Discharge summaries	Binary	Identification of obesity	Individual
Ramyaa et al [51], 2019	Questionnaire	Tabular	Energy balance components	Binary and continuous	Energy stores: body weight	Individual
Scheinker et al [50], 2019	2018 Robert Wood Johnson Foundation County Health Rankings	Tabular	Demographic factors, socioeconomic factors, health care factors, and environmental factors	Continuous	Obesity prevalence	County
Shin et al [49], 2019	Objective measure	Tabular	Upper body impedance and lower body anthropometric data	Continuous	BFP	Individual
Stephens et al [48], 2019	From recorded dialogue	Text	Dialogue	Binary	Weight management program	Individual
Blanes-Selva et al [47], 2020	EHR of HULAFEh	Tabular	32 variables	Binary	Identification of obesity	Individual
Dunstan et al [46], 2020	Euromonitor data set	Tabular	National sales of a small subset of food and beverage categories	Continuous	Nationwide obesity prevalence	Country
Fu et al [45], 2020	Clinical data	Tabular	Demographic characteristics, maternal anthropometrics, perinatal clinical history, laboratory tests, and postnatal feeding practices	Binary	Obesity	Individual
Kibble et al [44], 2020	Clinical data	Tabular	42 clinical variables	Binary	Mechanisms of obesity	Individual
Park et al [43], 2020	Openly accessible database	Image	Neuroimaging biomarkers	Continuous	BMI	Individual
Phan et al [42], 2020	Objective measure	Image	Neighborhood built environment characteristics	Binary, continuous	Obesity	State
Taghiyev et al [41], 2020	EHR	Tabular	Results of blood tests	Binary	Obesity	Individual
Xiao et al [40], 2020	Objective measure	Image	Vertical greenness level	Binary	Obesity	Individual
Yao et al [39], 2020	Objective measure	Tabular	Characteristics of body movement captured by smartphone’s built-in motion sensors	Continuous	BMI	Individual
Alkutbe et al [27], 2021	Self-reported and objective measures	Tabular	Weight, height, age, and gender	Binary and continuous	BFP	Individual
Bhanu et al [38], 2021	MRI	Image	SATi and VATj	Binary	Abdominal fat	Individual
Cheng et al [37], 2021	Objective measure	Tabular	Physical activity	Binary	Obesity	Individual
Delnevo et al [36], 2021	Questionnaire	Tabular	Positive and negative psychological variables	Binary and continuous	BMI values and BMI status	Individual
Lee et al [35], 2021	Objective measure	Tabular	64 independent variables: nationwide multicenter ultrasound data and maternal and delivery information	Continuous	BMI	Individual
Lin et al [34], 2021	Objective measure	Tabular	Key clinical variables	Binary	Obesity classification criterion	Individual
Pang et al [33], 2021	EHR data from pediatric big data repository	Tabular	Demographic variables and 54 clinical variables	Binary	Obesity	Individual
Park et al [32], 2021	Corpus of geotagged tweets	Text	Tweets	Binary and continuous	BMI and obesity	Individual
Rashmi et al [31], 2021	Objective measure	Image	600 thermograms	Binary	Obesity	Individual
Snekhalatha and Sangamithirai [30], 2021	Objective measure	Image	Thermal imaging	Binary	Diagnosis of obesity	Individual
Thamrin et al [29], 2021	Publicly available health data	Tabular	Risk factors for obesity	Binary	Obesity	Individual
Zare et al [28], 2021	BMI panel data set	Tabular	Kindergarten BMI z score	Binary	Obesity by grade 4	Individual

^aWHR: waist-hip ratio.

^bMRI: magnetic resonance imaging.

^cWC: waist circumference.

^dHC: hip circumference.

^eBFP: body fat percentage.

^fEHR: electronic health record.

^gNHANES: National Health and Nutrition Examination Survey.

^hHULAFE: Hospital Universitari i Politècnic La Fe.

ⁱSAT: subcutaneous adipose tissue.

^jVAT: visceral adipose tissue.