Table 9.
Temperament
| Study | Age at different assessments (in months) | Total number of participants | Number of EL siblings | Number of siblings with ASD outcome | Number of siblings with TD outcome | Number of siblings with another outcomea | Topic | Assessment method | Diagnostic instruments | Difference EL-ASD vs EL-TD and/or predicts ASD diagnosis | Main findings |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Brian et al. (2008) Canada [46] | 6–12 (time 1), 18 (time 2), 36 | 228 | 155 | 35 | 120 | – | Temperament: transition, reactivity | ADOS-G, AOSI | ADOS-G, ADI-R, expert clinical judgment according to DSM-IV-TR | Yes |
At time 2 (18 m): EL-ASD showed higher scores on transition compared to EL-TD and to TL EL-ASD showed higher levels of reactivity compared to EL-TD and TL transition and reactivity predicted ASD at 36 m |
| del Rosario et al. (2014) US [56] | 6, 12, 18, 24, 36 | 37 | 37 | 27 | 10 | – | Temperament: Activity, Adaptability, Approach | Carey Temperament Scale (CTS) in 3 versions: Revised Infant Temperament Questionnaire (RITQ) at 6 m, Toddler Temperament Questionnaire (TTQ) at 12 m and 24 m, Behaviour Style Questionnaire (BSQ) at 36 m | ADOS-G, SCQ, expert clinical judgment according to DSM-IV-TR | Yes |
On adaptability scale, EL-ASD had lower score than EL-TD at 6 m and at 12 m; EL-ASD had higher score than EL-TD at 24 m and 36 m On the approach scale, EL-ASD had lower score than EL-TD at 6 m; EL-ASD had higher score than EL-TD at 24 m and 36 m EL-ASD showed less active behaviour than EL-TD at 6 m and at 12 m but no differences afterwards |
| Garon et al. (2009) Canada [57] | 24, 36 | 192 | 138 | 34 | 104 | Not reported | Temperament: behavioural approach, effortful emotion regulation | Toddler Behaviour Assessment Questionnaire-Revised (TBAQ-R) | ADOS-G, ADI-R, MSEL, expert clinical judgment according to DSM-IV-TR | Yes |
At 24 m: EL-ASD scored significantly lower on behavioural approach than EL-TD and TL while EL-TD scored higher than TL TL had significant higher score on emotion regulation than EL-ASD and EL-TD, while EL-ASD and EL-TD did not show a significant difference 65% of EL-ASD were below average on behavioural approach and effortful emotion regulation; 74% of EL-TD showed higher than average behavioural approach and lower effortful emotion regulation; 70% of TL had higher than average effortful emotion regulation Behavioural approach better discriminated between EL-ASD and EL-TD than effortful emotion regulation. Effortful emotion regulation better discriminated between EL-ASD and TL than behavioural approach, although both were significant. Both functions distinguished EL-TD and TL, with behavioural approach being slightly higher than effortful emotion regulation |
| Garon et al. (2016) Canada [55] | 6–12, 24, 36 | 534 | 373 | 29 | 278 | Not reported | Temperament: positive affect, effortful control | Infant Behavior Questionnaire (IBQ) at 12 m, TBAQ-R at 24 m | ADOS-G, ADI-R, MSEL, expert clinical judgment according to DSM-IV-TR | Yes |
At 12 m EL were rated as higher on distress to limitations and fear compared to TL At 24 m EL were rated as higher on fear, sadness, anger, and lower on inhibitory control, soothability, attention focus, high pleasure, low pleasure than TL For EL, positive affect at 12 m predicted ASD symptoms at 36 m. This relationship was indirect and mediated by effortful control at 24 m. Lower effortful control score at 24 m predict more ASD symptoms at 36 m |
| Pijl et al. (2019) UK/NL [35] | 8, 14, 24, 36 | 199 | 133 | 24 | 75 | 34 | Temperament: surgency, negative affect, effortful control | IBQ-R at 8 m and 14 m, Early Childhood Behavior Questionnaire (ECBQ) at 24 m | ADOS-2, ADI-R, expert clinical judgment according to DSM-5 | Yes |
From 8 to 14 m EL-ASD had lower surgency scores than EL-TD and TL EL-ASD from 8 m on showed higher negative affect than EL-TD, EL-Other and TL EL-ASD at 14 m and at 24 m showed lower effortful control than EL-Other, EL-TD and TL A combination of all above temperament dimensions at 24 m as well as effortful control at 14 m and effortful control + negative affect at 24 m predicted ASD |
| Zwaigenbaum et al. (2005) Canada [33] | 6, 12, 24 | 88 | 65 | 7 | 46 | 12 | Temperament: inhibitory control, activity level, distress reactions, positive anticipation, affective responses | IBQ (at 6, 12 m), TBAQ (at 24 m) | ADOS-G, ADI-R, expert clinical judgment according to DSM-IV | Yes | Parents of EL-ASD described their children as having lower activity level at 6 m and more frequent and intense distress reactions, less inhibitory control, less positive anticipation and affective responses at 12 m compared to EL-TD and TL children |
aAtypical outcome: deficit in general cognition, motor functioning, language delay, Broader Autism Phenotype (BAP, social communication delay)