Reliability of the Language ENvironment Analysis system (LENA™) in European French
Résumé
In this study, we examined the accuracy of the
Language ENvironment Analysis (LENA) system in
European French. LENA is a digital recording device with
software that facilitates the collection and analysis of audio
recordings from young children, providing automated measures
of the speech overheard and produced by the child.
Eighteen native French-speaking children, who were divided
into six age groups ranging from 3 to 48 months old, were
recorded about 10–16 h per day, three days a week. A total of
324 samples (six 10-min chunks of recordings) were selected
and then transcribed according to the CHAT format. Simple
and mixed linear models between the LENA and human adult
word count (AWC) and child vocalization count (CVC) estimates
were performed, to determine to what extent the automatic
and the human methods agreed. Both the AWC and
CVC estimates were very reliable (r = .64 and .71, respectively)
for the 324 samples. When controlling the random factors
of participants and recordings, 1 h was sufficient to obtain a
reliable sample. It was, however, found that two age groups
(7–12 months and 13–18 months) had a significant effect on
the AWC data and that the second day of recording had a
significant effect on the CVC data. When noise-related factors
were added to the model, only a significant effect of signal-tonoise
ratio was found on the AWC data. All of these findings
and their clinical implications are discussed, providing strong
support for the reliability of LENA in French.