Longitudinal Epidemiological Study of Autism Subgroups Using Autism Treatment Evaluation Checklist (ATEC) Score.

ASD diagnosis was not confirmed, because the ATEC questionnaire does not include diagnosis, so some participants may not have had ASD. Participants were voluntary online completers, not actively recruited, so the sample may not represent children with ASD in clinical services. The analysis required at least three questionnaires within 2 years, with the first and last evaluations at least 1 year apart, so children whose parents stopped completing the questionnaire were not included. The excluded groups were children with initial ATEC total scores below 20, children whose first evaluation was before age 2, and children older than 12. No treatment was assigned or compared, so score changes cannot be attributed to therapy. The ATEC mixes developmental and symptom-specific items, so age-related change can be mistaken for change in ASD severity. Severity groups based only on initial ATEC score may be an artifact because initial score is not age-adjusted. The paper does not identify why non-English-speaking countries showed larger score reductions. Parent reports may be biased on a single assessment, although the study used repeated measures to look at patterns.

No funding or conflict-of-interest statement is supplied in the provided text. One author is identified as being from Autism Research Institute, which distributed the ATEC questionnaire, and the ATEC was developed by Rimland and Edelson.

Do not read the score reductions as evidence that a treatment worked. No treatment was tested; the study followed parent-reported ATEC scores over time and cannot separate natural development from therapy effects.