Table 2.
The baseline characteristic of the six included RCTs.
| Study’s First Author, Year | N (% Female) |
Age (Mean ± SD) (Median (IQR)) |
Inclusion Criteria | Exclusion Criteria |
|---|---|---|---|---|
| Elder et al., 2006 [21] | Intervention: 7 Control: 7 (20% Female) |
7.3 ± 4.1 years | Diagnosis of ASD according to DSM-IV criteria | Children with medical histories and/or physical examinations indicated that they had physical or sensory-impairments or significant medical problems, including celiac disease. |
| Gonzalez-Domenech et al., 2019 [39] | Intervention: 15 Control: 16 (46% Female) |
Overall 8.9 years | Diagnosis of ASD according to the tenth edition of the International Classification of Diseases (ICD-10). | Patients diagnosed with an allergy to gluten or casein; patients who had previously excluded gluten and/or casein from their diet; patients who were likely to not adhere to the diet properly. |
| Johnson et al., 2011 [36] | Intervention: 8 Control 14 (22% Female) |
Intervention 40.1 ± 9.3 months Control 39.5 ± 8.7 months |
Diagnosis of ASD according to DSM-IV criteria | Not reported |
| Knivsberg et al., 2002 [20] | Intervention: 10 Control: 10 (Not reported) |
Intervention 91 months Control 86 months |
Participation included only children with both the diagnosis of autism and abnormal urinary peptide patterns. | Not reported |
| Navarro et al., 2015 [38] | Intervention: 6 Control: 6 (Not reported) |
Intervention 5.5 years Control 6 years |
Diagnosis of ASD according to DSM-IV criteria | Children with food allergies, celiac disease, inflammatory bowel disease, and infectious GI diseases. Children with neurological problems that could interfere with proper evaluation of behavior. Children with parents unwilling to undertake the GDF diet during the study. |
| Whiteley et al., 2010 [37] | Intervention: 38 Control: 34 (11% Female) |
Intervention 94.2 (IQR 76.6–118) months Control 69.4 (ICR 76.3–120.3) months |
Children diagnosed with pervasive developmental disorder (ICD-10 code F84) | Children with co-morbid diagnoses of epilepsy, fragile-X syndrome, tuberous sclerosis, or a developmental age below 24 months |
Abbreviations: ASD: Autistic Spectrum Disorder; DSM-IV: Diagnostic and Statistical Manual ICD: International Classification of Diseases; GI: Gastrointestinal.