Psychometric properties of the French Infant-Toddler Working Alliance Inventory Short version (IT-WAI-S)

Area of Science:

• Child Psychology
• Psychotherapy Research
• Developmental Psychology

Background:

• Therapeutic alliance is crucial in child therapy but understudied in infants and toddlers.
• Existing tools lack specific adaptations for this young population.
• The Infant-Toddler Working Alliance Inventory-Short form (IT-WAI-S) was developed based on the Working Alliance Inventory.

Purpose of the Study:

• To evaluate the psychometric properties of the original French IT-WAI-S tool.
• To assess two versions: parent (IT-WAI-SP) and therapist (IT-WAI-STh).
• To determine the reliability, validity, and predictive utility of the IT-WAI-S scales.

Main Methods:

• 227 families with children aged 18-48 months presenting emotional/behavioral disorders participated.
• The IT-WAI-S scales were administered during the first three therapy sessions.
• Psychometric properties including acceptability, internal validity, reliability, and predictive validity were analyzed.

Main Results:

• Factor analyses confirmed a three-factor structure (Negative Experience, Positive Alliance, Alliance with Child) for both versions.
• Acceptability, reproducibility, and construct validity were satisfactory for IT-WAI-SP and IT-WAI-STh.
• Both versions predicted child outcomes; IT-WAI-SP also predicted mother's outcomes, while IT-WAI-STh showed higher reproducibility.

Conclusions:

• The IT-WAI-S parent and therapist versions exhibit strong psychometric properties.
• These tools are suitable for investigating therapeutic alliance in infant and toddler therapy.
• The findings support the use of IT-WAI-S for research and clinical practice with young children and their families.