| AB | adaptive behaviors |
| ABC | Autism Behavior Checklist |
| AE | affective expression |
| ASD | Autism Spectrum Disorder |
| ATEC | Autism Treatment Evaluation Checklist |
| CARS | Children Autism Rating Scale |
| CBS | cystathionine-beta-synthase |
| CMB | characteristic motor behaviors |
| CVB | characteristic verbal behaviors |
| CVP | cognitive verbal/preverbal |
| DHFR | dihydrofolate reductase |
| EL | expressive language |
| FM | fine motor |
| GM | gross motor |
| GSH | reduced glutathione |
| GSSG | oxidized glutathione disulfide |
| Hcy | homocysteine |
| PB | problem behaviors |
| PEP-3 | Psychoeducational Profile-third edition |
| PSC | personal self-care |
| RL | receptive language |
| SAM | S-adenosylmethionine |
| SR | social reciprocity |
| TEACCH | The Treatment and Education of Autistic and Related Communication Handicapped Children |
| VMI | visual motor imitation |