Children aged 18 to 24 months are screened for ASD to assist in early detection, consistent with current American Academy of Pediatrics’ recommendations [17]. Despite the advances in ASD screening and evaluation, the mean age of diagnosis is still 4–5 years [18]. The age of ASD diagnosis depends on many factors and to label a child “autistic” may require a multidisciplinary team [19] or multiple medical visits (4–5 on average with the extremes of 1 and 29) [20]. While the high demand of services due to a recent increase in ASD prevalence delays its diagnosis in developed countries, the lack of trained health professionals and the socio-cultural representation of the disorder may prevail in Mali. Similar to sub-Sahara Africa, in the Arab world, culture may significantly influence the age of noticing abnormality and the ways of investigating and treating autism [21].
The age of ASD identification was after 36 months old in 76.8% (Table 1). In two separate U.S national surveys, the 2011–2012 National Survey of Children’s Health (n = 95,677) and the 2009–2010 National Survey of Children with Special Health Care Needs (n = 371,617), many parents of children with ASD reported identification after 3 years old with 1/3 to 1/2 of cases after 6 years old [21].
In our cohort, parental concerns on their children’s development were mostly about verbal communication (54.1%) and reciprocal social interaction (43.8%) (Table 2). This result corroborates the findings of Richards et al. They reported that over 90% (n = 532) of the parents brought up concerns during well child visits and 78.6% were about speech and verbal communication [22]. Children whose parents expressed concerns about their child's verbal communication experienced earlier ages for all outcomes when compared to children of parents who did not have verbal communication concerns [23]. Such finding highlights the evolution of parental concerns over time. In mid-2000s, parents of autistic children used to be concerned over either a delayed diagnosis of physical disabilities, such as hearing impairment, cerebral palsy [24], learning difficulty, being bullied, stress-coping, or achievement [25].
The median age of being able to smile (social and non-social) for the first time was 4 months old and the mean age was 7.7 months old ± 7.9 with the extremes of 2 and 36 months old (Table 3). Anticipatory smiling levels in the first year may predict ASD diagnosis or continuous ASD severity outcomes [26]. The median age of imitation was 24 months and the average age of 45.23 months ± 44.8 with the extremes of 4 and 168 months old (Table 3). Immediate and deferred imitations of adults by children with ASD were strongly associated with language ability at age 3–4 years and communication development from age 4 to 6.5 years [27], but the loss of social communication skills is highly variable (its rate, timing and severity) in ASD and it usually occurs in the period between 9 and 24 months [28, 29].
The median age of storytelling in our cohort was 49 months and the mean age was 50.4 months ± 21.5 with the extremes of 36 and 99 months (Table 3). Difficulties in storytelling have been reported in children with ASD [30, 31]. While the contribution of problematic use of subject pronoun has been demonstrated in the difficulties in storytelling in school-aged children with ASD [32], speculation has been on whether or not difficulties in orientation in time and space play an important role in the process [33].
Motor development is critical to the overall development of the child. In our cohort, the age of motor skill acquisition was very variable. For instance, the mean age of reaching out for an object was 16.1 months ± 23.8 with the extremes 3 and 144 months (Table 3). The gross and fine motor skills of young children with ASD are delayed and become progressively more delayed with age [34, 35], but the great variability in motor skill acquisition makes it challenging the universality for health professionals [36]. The median age of walking (AOW) in our cohort was 14.50 months and the mean age was 19.5 months ± 44.8 with the extremes of 7 and 72 months (Table 3). Reindal et al. reported a mean AOW of 15.3 months ± 5.5 in children with ASD versus 14.1 months ± 3.4. AOW is reported to be later in autism spectrum disorder (ASD) compared with typical normal development [37].
None of our targeted factors (male gender, Bambara ethnicity, impaired reciprocal social interaction, impaired verbal communication, repetitive behaviors, the presence of epilepsy, presence of strabismus, and the absence of crying at birth) was significantly associated with the age of first medical visit (the cutoff was 18 months) or the age of identification of autistic disorder (the cutoff was 36 months (Tables 4–5). This finding might have resulted from the small size of our sample. Otherwise, evidence from the literature are compelling for the association of some (if not all) of these studied factors with early detection and diagnosis of autism spectrum disorders.
Parental concerns are more pronounced in males and females with ASD. This may have many plausible explanations. First, even with higher ASD prevalence in both sexes, core ASD symptomology are easily presentable in males, and females are too good in camouflaging their symptoms, which may result in sex differences in parental concerns after age 5 years [38–43]. Second, females experienced less unusual stereotyped and repetitive behaviors than males due to genetic (Y chromosome) and hormonal factors (fetal testosterone) and they have an increased prevalence of internalizing problems [40, 44]. Third, females were found to receive lower scores than males particularly on modules 2 and 3 of the Childhood Autism Rating Scale scores (CARS) [45]. Finally, Baron-Cohen’s extreme male theory may induce a stronger examiner bias toward males than females with ASD [46].
Black parents reported significantly fewer autism concerns and fewer social and restricted and repetitive behavior concerns as compared to White parents [47]. The Bambara are the largest ethnic group in Mali with up to 36.5% of the total population. They also present in significant percentages in Guinea Conakry, Burkina Faso, Niger, Ivory Coast, and Mauritania [48]. In addition, the other disorders in Tables 3–5 (epilepsy, strabismus, and absence of crying at birth) are very frequent in autism [49–51]. The absence of crying at birth and seizure episode in childhood were highly associated with autism risk in Brazil (OR 5.75; 95%CI 3.37–9.81) [5]. Even though, strabismus has a low prevalence in Africa [52], it has a strong cultural representation in the West African society in general and in Mali in particular. It is referred to as “the hen is looking at the cloudy sky” in Mali and it is a distinctive and particular trait which, a child can be labeled with among his/her peer.
Which one of the impaired reciprocal social interaction, afflicted verbal communication and repetitive behaviors in children with ASD draws first the attention of parents? The answer to this question depends on multiple factors. Truly, ASD is a spectrum in the real sense of the word. When all domains of the child’s development are affected moderately or severely at the same time, parents usually notice as early as possible, especially when they have another child with normal developmental for comparison [53]. When language skills lag far behind, parental concerns habitually raise between 18 and 24 months old of age [22, 53].
Altogether, assessing parental concerns about children with ASD may be more challenging and more complex than one may initially think. Core symptoms of ASD alone may not explain at which extent parents are concerned and stressed out their child development and well-being. A more comprehensive assessment should consider other aspects such as sleep and eating problems, parenting stress, the specific burden on mothers with subsequent poor marital relationship [46, 54–56].