Purpose: The Language ENvironment Analysis (LENA) is a technological tool designed for comprehensive recordings and automated analysis of young children's daily language and auditory environments. LENA recordings play a crucial role in both clinical interventions and research, offering insights into the amount of spoken language children are exposed to in their homes, including adult word count (AWC) and child vocalization count (CVC). Although LENA was initially developed for American English, it has been validated in various other languages. This study aimed to evaluate the reliability of LENA in a Swedish context by comparing its automatic estimates with human transcriptions.

Method: Thirty-six children aged 11–29 months participated in the validation study. A total of 540 min (9 hr) of recordings were transcribed by one experienced speech-language pathologist and two special educators. Interrater agreement over 150 min was notably higher for CVC (intraclass correlation coefficient [ICC] = .97, 95% confidence interval [CI] [.91, .99], r = .96, p < .001) compared to AWC, which yielded an ICC of .82 (95% CI [.15, .96], r = .80, p = .006).

Results: Both estimated CVC and AWC (n = 36) were significantly correlated with human transcriptions (r = .79 and .82, respectively; p < .001).

Conclusions: The findings align with prior validation studies, indicating that LENA is suitable for use in a Swedish context, particularly for families with children aged 11–29 months. Nonetheless, additional validation studies are necessary, particularly focusing on younger infants, to enhance our understanding of the tool's reliability in preverbal children and their caregivers.