Abstract
Background: Concerns have been raised that scores on standard measures of autism spectrum disorder (ASD) symptoms may differ as a function of sex. However, these findings are hindered by small female samples studied thus far. The current study evaluated if, after accounting for age, IQ, and language level, sex affects ASD severity estimates from diagnostic measures among children with ASD. Methods: Data were obtained from eight sources comprising 27 sites. Linear mixed-effects models, including a random effect for site, were fit for 10 outcomes (Autism Diagnostic Observation Schedule [ADOS] domain-level calibrated severity scores, Autism Diagnostic Interview–Revised [ADI-R] raw scores by age-based algorithm, and raw scores from the two indices on the Social Responsiveness Scale [SRS]). Sex was added to the models after controlling for age, NVIQ, and an indicator for language level. Results: Sex significantly improved model fit for half of the outcomes, but least square mean differences were generally negligible (effect sizes [ES] < 0.20), increasing to small to moderate in adolescence (ES < 0.40). Boys received more severe RRB scores than girls on both the ADOS and ADI-R (age 4 + algorithm), and girls received more severe scores than boys on both SRS indices, which emerged in adolescence. Conclusions: This study combined several available databases to create the largest sample of girls with ASD diagnoses. We found minimal differences due to sex beyond other known influences on ASD severity indicators. This may suggest that, among children who ultimately receive a clinical ASD diagnosis, severity estimates do not systematically differ to such an extent that sex-specific scoring procedures would be necessary. However, given the limitations inherent in clinically ascertained samples, future research must address questions about systematic sex differences among children or adults who do not receive clinical diagnoses of ASD. Moreover, while the current study helps resolve questions about widely used diagnostic instruments, we could not address sex differences in phenotypic aspects outside of these scores.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 97-106 |
| Number of pages | 10 |
| Journal | Journal of Child Psychology and Psychiatry and Allied Disciplines |
| Volume | 62 |
| Issue number | 1 |
| DOIs | |
| State | Published - Jan 2021 |
Funding
This work was supported by grants from the National Institute of Child Health and Human Development (R01HD093012 to S.L.B. and R01HD081199 to C.L.), the National Institute of Mental Health (R01MH081873 to C.L.), and the Autism Science Foundation (ASP-002 to S.L.B.). This work was also supported by the intramural research program of the NIMH (ZIC-MH002961 to A.T.). The Autism Treatment Network activity was supported by Autism Speaks and conducted through the Autism Speaks Autism Treatment Network. This information or content and conclusions are those of the author and should not be construed as the official position or policy of, nor should any endorsements be inferred by Autism Speaks. The authors are grateful to all of the families at the participating Simons Simplex Collection (SSC) sites, as well as the principal investigators (A. Beaudet, R. Bernier, J. Constantino, E. Cook, E. Fombonne, D. Geschwind, R. Goin-Kochel, E. Hanson, D. Grice, A. Klin, D. Ledbetter, C. Lord, C. Martin, D. Martin, R. Maxim, J. Miles, O. Ousley, K. Pelphrey, B. Peterson, J. Piggot, C. Saulnier, M. State, W. Stone, J. Sutcliffe, C. Walsh, Z. Warren, E. Wijsman). The authors appreciate obtaining access to phenotypic data on SFARI Base. Approved researchers can obtain the SSC population dataset described in this study by applying at https://base.sfari.org. The authors are grateful to the parents and children who participate in the Pathways in ASD study, and to the current and past members of the study team, including principal and coinvestigators (P. Szatmari, P. Mirenda, C. Waddell, L. Zwiagenbaum, J. Volden, T. Vaillancourt, T. Bennett, I. Smith, M. Elsabbagh, S. Georgiades, E. Duku, W. Ungar, C. Kerns). The authors are also grateful to our funders, the Canadian Institutes for Health Research, Kids Brain Health, Autism Speaks, the Sinneave Family Foundation, and Alberta Innovates Health Solutions. S.L.B. has received royalties from the ADOS-2. All profits from her research are donated to charity. C.L. has received royalties from the ADI-R, ADOS, and ADOS-2. All profits from her research are donated to charity. The remaining authors have declared that they have no competing or potential conflicts of interest.Key points Researchers and clinicians have increasingly questioned whether there are sex differences on measures used to determine ASD diagnosis and symptom severity. Previous investigations of how sex affects scores have been hindered by small groups of female participants, preventing adequate consideration of other variables known to affect scores on ASD symptom measures. Results of the current study indicated that among youth already diagnosed with ASD, select scores from the ADI-R, SRS, and ADOS-2 differ by sex, with girls receiving less severe scores, in the area of RRBs. However, effects of sex were small and likely of limited clinical significance. Clinicians must be sufficiently trained to recognize the widely varying presentations of individuals with ASD across the spectrum of age, IQ, language level, and ASD severity. Attending to how sex and other sociodemographic variables may affect symptom presentation is yet another component of best clinical practice. Researchers and clinicians have increasingly questioned whether there are sex differences on measures used to determine ASD diagnosis and symptom severity. Previous investigations of how sex affects scores have been hindered by small groups of female participants, preventing adequate consideration of other variables known to affect scores on ASD symptom measures. Results of the current study indicated that among youth already diagnosed with ASD, select scores from the ADI-R, SRS, and ADOS-2 differ by sex, with girls receiving less severe scores, in the area of RRBs. However, effects of sex were small and likely of limited clinical significance. Clinicians must be sufficiently trained to recognize the widely varying presentations of individuals with ASD across the spectrum of age, IQ, language level, and ASD severity. Attending to how sex and other sociodemographic variables may affect symptom presentation is yet another component of best clinical practice. This work was supported by grants from the National Institute of Child Health and Human Development (R01HD093012 to S.L.B. and R01HD081199 to C.L.), the National Institute of Mental Health (R01MH081873 to C.L.), and the Autism Science Foundation (ASP‐002 to S.L.B.). This work was also supported by the intramural research program of the NIMH (ZIC‐MH002961 to A.T.). The Autism Treatment Network activity was supported by Autism Speaks and conducted through the Autism Speaks Autism Treatment Network. This information or content and conclusions are those of the author and should not be construed as the official position or policy of, nor should any endorsements be inferred by Autism Speaks. The authors are grateful to all of the families at the participating Simons Simplex Collection (SSC) sites, as well as the principal investigators (A. Beaudet, R. Bernier, J. Constantino, E. Cook, E. Fombonne, D. Geschwind, R. Goin‐Kochel, E. Hanson, D. Grice, A. Klin, D. Ledbetter, C. Lord, C. Martin, D. Martin, R. Maxim, J. Miles, O. Ousley, K. Pelphrey, B. Peterson, J. Piggot, C. Saulnier, M. State, W. Stone, J. Sutcliffe, C. Walsh, Z. Warren, E. Wijsman). The authors appreciate obtaining access to phenotypic data on SFARI Base. Approved researchers can obtain the SSC population dataset described in this study by applying at https://base.sfari.org . The authors are grateful to the parents and children who participate in the Pathways in ASD study, and to the current and past members of the study team, including principal and coinvestigators (P. Szatmari, P. Mirenda, C. Waddell, L. Zwiagenbaum, J. Volden, T. Vaillancourt, T. Bennett, I. Smith, M. Elsabbagh, S. Georgiades, E. Duku, W. Ungar, C. Kerns). The authors are also grateful to our funders, the Canadian Institutes for Health Research, Kids Brain Health, Autism Speaks, the Sinneave Family Foundation, and Alberta Innovates Health Solutions. S.L.B. has received royalties from the ADOS‐2. All profits from her research are donated to charity. C.L. has received royalties from the ADI‐R, ADOS, and ADOS‐2. All profits from her research are donated to charity. The remaining authors have declared that they have no competing or potential conflicts of interest. Key points
Keywords
- Sex differences
- autism spectrum disorder
- restricted and repetitive behavior
- social impairment
ASJC Scopus subject areas
- Pediatrics, Perinatology, and Child Health
- Developmental and Educational Psychology
- Psychiatry and Mental health