Table 1.
Characteristics of the included studies.
| No. | Study Ref. | Author/Year | Disease | Ethnicity | Sample size Cases/controls | Age (years) Cases/controls | Gender | Age of Disease onset (years) | Disease duration (years) | Clinical assessment | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Female (%) Cases/controls | Male (%) Cases/controls | ||||||||||
| 1 | Giulivi et al. (37) | Giulivi/2010 | ASD | Caucasian | 10/10 | 2–5 | 10/10 | 90/90 | NP | NP | ADI-R, ADOS |
| 2 | Gu et al. (38) | Gu/2013 | ASD | Caucasian | 14/12 | 10.36 ± 1.46/10.83 ± 1.72 | 3/3 | 11/9 | NP | NP | DSM-IV |
| 3 | Tang et al. (29) | Tang/2013 | ASD | Caucasian | 20/25 | 3–60/2–65 | 8/12 | 90/88 | NP | NP | DSM-IV, ADI-R |
| 4 | Napoli et al. (39) | Napoli/2014 | ASD | Caucasian | 10/10 | 2–5 | 10/10 | 90/90 | NP | NP | ADI-R, ADOS |
| 5 | Chen et al. (40) | Chen/2015 | ASD | Asian | 78/83 | 3.78/3.9 | 11.5/19.2 | 88.4/80.7 | 2.05 ± 0.7 | 2.49 ± 1.2 | CARS, ABC |
| 6 | Yoo et al. (26) | Yoo/2016 | ASD | Asian | 100/100 | 8.2/7.6 | 17/39 | 83/61 | NP | NP | DSM-IV, ADI-R |
| 7 | Wong et al. (41) | Wong/2016 | ASD | Mixed | 66/46 | 3.9 ± 0.1/3.5/±0.1 | 15.4/12.9 | 84.6/87.1 | NP | NP | ADOS |
| 8 | Valiente-Palleja et al. (27) | ValientePalleja`/2018 | ASD | Caucasian | 122/112 | 40.7 ± 8.3/42.4 ± 11.4 | 34.4/55.4 | 65.5/44.6 | NP | NP | DSM-IV, ADI-R |
| 9 | Carrasco et al. (42) | Carrasco/2019 | ASD | Caucasian | 12/12 | 6–13 | 8.3/25 | 91.6/75 | NP | NP | DSM-IV |
| 10 | Kim et al. (43) | Kim/2019 | ADHD | Asian | 70/70 | 9.8 ± 2.6/10 ± 2.6 | – | 44/44 | NP | NP | K-SADS-PL DSM-IV |
| 11 | Singh et al. (28) | Singh/2019 | ASD | Caucasian | 12/9 | 5.14 ± 1.5/6.60 ± 2.1 | 25/44 | – | NP | NP | OACIS-S, ABC, SRS |
| 12 | Öğütlü et al. (30) | Öğütlü/2020 | ADHD | Asian | 56/56 | 9.88 ± 2.60/9.96 ± 2.78 | 37.5/37.5 | 62.5/62.5 | NP | NP | K-SADS-PL DSM-IV |
| 13 | Bam et al. (44) | Bam/2021 | ASD | Mixed | 68/40 | 6–12 | NP | NP | NP | NP | ADOS |
| 14 | Öğütlü et al. (31) | Öğütlü/2021 | ADHD | Asian | 28 | 10.0 ± 3.4/9.7 ± 2.1 | 64.3/28.6 | 35.7/71.4 | NP | NP | K-SADS-PL DSM-IV |
ASD, autism spectrum disorder; ADHD, attention deficit hyperactivity disorder; NP, not provided; CARS, Childhood Autism Rating Scale; ABC, Autistic Behavior Checklist; DSM-IV, Diagnostic and Statistical Manual of Mental Disorders – fourth edition; ADI-R, Autism Diagnostic Interview-Revised; ADOS, Autism Diagnostic Observation Schedule; OACIS-S, clinician-rated Ohio Autism Clinical Impression Scale–Severity; SRS, Social Responsiveness Scale; K-SADS-PL, Schedule for Affective Disorders and Schizophrenia for School Age Children Present and Lifetime version; ADOS, Autism Diagnostic Observation Schedule; SRS, Social Responsiveness Scale.