The AQ is valuable as a quick screening instrument for core trait dimensions of autism, and has been widely used globally in clinical practice and autism research. To our knowledge, the present study is the first attempt to validate the abridged version of the AQ scale in the Arabic language. The study also provides the first epidemiological overview of the continuous distribution of autism traits in a nonclinical adult Arabic-speaking population from an Arab country and culture of the Middle East. Our findings showed that the Arabic version of the AQ-28 exhibited a five-factor structure that was invariant across sex, and satisfactory internal consistency. In addition, the scale demonstrated good concurrent validity as evidenced by appropriate patterns of correlations with measures of attachment loneliness, depression and anxiety. These results suggest that the AQ-28 is suitable for use among Arabic-speaking adults from the general population to screen for ASD.
In terms of factorial validity, the current results were able to replicate the original five-factor model found by Hoekstra et al. (Hoekstra et al., 2011) in an Arabic-speaking population and country. Other linguistic versions of the AQ-28 validated in different countries and settings also landed support to the proposed multifactorial model (Ameli, Ghaderi, Aslzaker Lighvan, et al., 2019; Chee et al., 2024; Kuenssberg et al., 2014; Lugo-Marín et al., 2019). Furthermore, findings of the reliability analysis showed an acceptable internal consistency for the AQ-28 (Cronbach ranging from .57 to .91), thus supporting the results previously found in the original (α ranging from .77 to .86) (Hoekstra et al., 2011) as well as other validation studies (e.g., Spanish, α between .79 and = .88 (Lugo-Marín et al., 2019); Dutch, α between .72 and .89 (Chee et al., 2024); Malaysian, α between 0.50 and 0.88 (Chee et al., 2024); Persian, α between .48 and .95).
As a multidimensional measure, the AQ-28 has not only the capacity to offer an overall evaluation of autism trait levels through a total scale score, but also the ability to evaluate trait dimensions independently at the subscale level. In particular, the scale measures five clearly defined domains, assessing attention switching difficulties (‘Switching’), difficulties with imagination (‘Imagination’), a preference for routine (‘Routine’), difficulties with social skills (‘Social skills’), and a fascination for numbers/patterns (‘Numbers/patterns’). This multi-dimensional approach to the examination of the broader Autism Phenotype can be highly valuable in determining the differential association between some autism domains and certain individual characteristics. For instance, more social difficulties were distinctly and specifically linked to the presence of a local processing bias in non-clinical individuals (Russell-Smith et al., 2012). Other research showed that imagination difficulties are specific predictors of difficulty in perceiving speech in noise in non-autistic individuals (Tsuji et al., 2024). Therefore, as autistic traits are heterogeneous in nature, it is crucial to not treat all autistic individuals as a homogenous group, and rather explore the shared as well as distinct characteristics of particular domains of autism using a psychometrically-sound multifactorial measure such as the AQ-28.
Measurement invariance was tested and established across male and female respondents at the configural, metric, and scalar levels. This psychometric property is a necessary step for the questionnaire validation to ensure meaningful group comparisons based on observed AQ-28 scores and guarantee that any observed differences are not caused by test bias (Wicherts & Dolan, 2010). Consistent with our findings, cross-sex measurement invariance has previously been reported for the AQ in both autistic and non-autistic individuals (English et al., 2020; Grove et al., 2017). In our study, mean sum scores observed in male participants were significantly higher than those displayed by females. In the original validation study (Baron-Cohen et al., 2001), sex differences in AQ scores were observed, with male students scoring higher on all AQ subscales than their female counterparts, with the exception of attention to detail. However, as measurement invariance was not analyzed, it is unclear whether the differences seen reflect true differences or sex differential functioning of the scale’s items. Likewise, studies in Japanese (Kunihira et al., 2006) and Polish (Pisula et al., 2013) adult students found that males displayed greater severity of autistic traits than females, scoring higher in all AQ scores but attention to detail. A systematic review encompassing 73 articles and 6,934 participants showed that males and female adults from the general population had significantly different mean AQ scores, with males scoring greater than females; whereas no significant sex difference was found in AQ scores in the clinical ASD population (Eyuboglu et al., 2018). These observations along with our findings might suggest that sex differences in AQ scores seem to be cross-culturally independent. However, mixed findings have also been previously reported in the literature, with studies indicating either the lack of sex differences in AQ scores (Hurst, Nelson-Gray, et al., 2007), or even slightly higher (but still non-significant) AQ scores exhibited by females compared to males (Hurst, Mitchell, et al., 2007). Altogether, there remains a debate around the extent to which an apparent disparity exists between males and females in the incidence of autism (Constantino & Charman, 2012; Dworzynski et al., 2012). More research in various cultural contexts and geographical locations are required to further elucidate the nature of sex differences. This research should consider using autism measures that are psychometrically invariant for males and females to rule out test bias as possible explanations for between-group differences in scores.
This study’s findings provided evidence for concurrent validity and indicated that autistic traits as measured by the Arabic AQ-28 correlated negatively with secure attachment and positively with loneliness, depression and anxiety. These results are in line with earlier studies consistently showing that sub-threshold Autistic Traits among adults from the general population are associated and increased susceptibility towards the development of different psychopathological trajectories (Dell'Osso et al., 2019). For instance, autism is assumed to hamper the development of secure attachment, as previous studies also found that only a small proportion of ASD individuals were classified as having a secure attachment style (Teague et al., 2017). In addition, people with ASD tend to develop secure attachment representations to a lesser extent than healthy controls (Giannotti & de Falco, 2021). In agreement with our findings, prior research also reported that adults with more pronounced autistic traits are likely to experience loneliness more frequently and more intensely than their non-autistic counterparts (Grace et al., 2022), and to develop depression and anxiety symptoms (Hollocks et al., 2019). Taken together, our findings support the clinical utility of the AQ-28 for autistic traits assessment and ASD diagnosis screening, as well as for identifying co-occurring psychopathology.
Study limitations
This study has some limitations that can guide future lines of research. First, the target population consisted of adults from the general population, which can limit the generalizability of results to other clinical and non-clinical populations, such as students or individuals diagnosed with ASD or with schizophrenia. Second, due to snowball sampling, the sample representativeness may be affected. Third, female and highly educated participants were slightly overrepresented, which could have influenced the results. At the same time, it can be suggested that the sample size was large enough for the psychometric testing. Fourth, the study involved Arabic-speaking adults from a single country. Future studies using a multinational sample could specifically examine cross-country differences in the factor structure of the AQ-28. Finally, additional psychometric properties of the Arabic AQ-28, such as test-retest reliability and cut-off score for predicting ASD, still need to be investigated.
Implications and future perspectives
These limitations aside, the current study extends and makes a major contribution to the international literature on autism by validating, for the first time, the AQ-28 into Arabic. The Arabic version of AQ-28 consists of 28 statements referring to five functional domains, which is almost half the length of the original long-form. Screening for autistic traits in clinical and community settings using 50 items may be too demanding, particularly in the developing-Arab-countries’ settings, where time, resources and costs can be a strain. Due to its brevity and good psychometric qualities, the AQ-28 allows to reduce the burden of test administration, while preserving the validity and reliability of its scores. This would facilitate its routine application in clinical settings. Moreover, multi-group analyses provided evidence of the measurement equivalence of the scale across sex, making it possible to make accurate between-sex group comparisons on AQ-28 scores.
It needs to be emphasized that the AQ-28 is a screening but not a diagnostic instrument. Individuals endorsing high scores on this scale do not necessarily have ASD. To establish a clinical diagnosis and conduct detailed clinical research, more comprehensive assessments and interviews remain essential to determine the presence and clinical significance of key features and core symptoms of autism (Baron-Cohen et al., 2001).
To date, the field of autism research in adults has not yet emerged in Arab countries. It is our hope that the Arabic-language version of the AQ-28 provided by this study will generate interest among researchers in this important area of research, and help to galvanize efforts to better understand the nature and etiology of the broader autism phenotype in the general population across cultures, as well as implications for practice and health policy.