Researcher Choices for Infant Sleep Assessment: Parent Report, Actigraphy, and a Novel Video System

Abstract

Incorporating infant sleep, either as a predictor or as an outcome variable, into interdisciplinary work has become increasingly popular. Sleep researchers face many methodological choices that have implications for the reliability and validity of the data. Here, the authors directly investigated the impact of design and measurement choices in a small, longitudinal sample of infants. Three sleep measurement techniques—parent-reported sleep diaries, actigraphy (Micromini Sleep Watch), and a commercial videosomnography (Nanit)—were included, using actigraphy as the baseline. Nine infants’ sleep (4 girls) was measured longitudinally using all three measurement techniques. Nanit provided summary statistics, using a proprietary algorithm, for nightly sleep parameters. The actigraphy data were analyzed with both the Sadeh Infant and Sadeh algorithms. The extent to which measurements converged on sleep start and end time, number of wake episodes, sleep efficiency, and sleep duration was assessed. Measures were positively correlated. Difference scores revealed similar patterns of greater sleep estimation in parent reports and Nanit compared with actigraphy. Bland-Altman plots revealed that much of the data were within the limits of agreement, tentatively suggesting that Nanit and actigraphy may be used interchangeably. Graphs display significant variability within and between individual infants as well as across measurement techniques. Potential confounding variables that may explain the discrepancies between parent report, Sadeh Infant, Sadeh, and Nanit are discussed. The findings are also used to speak to the advantages and disadvantages of design and measurement choices. Future directions focus on the unique contributions of each measurement technique and how to capitalize on them.

Keywords:

• Actigraphy
• infant
• parent report
• sleep measurement
• videosomnography

Acknowledgments

Portions of this research were presented at Pediatric Sleep Medicine, Naples, FL, November 2019. We gratefully acknowledge the assistance of Lobna Abdllatif, Sarah Abdel Fatah, Dr. Natalie Barnett, Assaf Glazer, Roy Peleg, and Yanai Ankri in data collection and coding.

Data availability statement

Data that support the findings of this study are available from the corresponding author upon reasonable request.

Disclosure statement

We have no known conflict of interest to disclose.

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

This work was supported by the National Science Foundation Division of Behavioral and Cognitive Science [1551703] and Professional Staff Congress–City University of New York [Award No. 68597-00 46] to SEB.

Notes on contributors

Melissa N. Horger

Melissa Horger is a doctoral candidate at the Graduate Center of the City University of New York. Her work centers around the development of REM and NREM and novel forms of sleep measurement.

Ruth Marsiliani

Ruth Marsilliani is a masters student at the College of Staten Island in the Center for Developmental Neuroscience and Developmental Disabilities. She focuses on maxillofacial development, tongue ties, and how they relate to sleep during infancy

Aaron DeMasi

Aaron DeMasi is a doctoral candidate at the Graduate Center of the City University of New York. His research aims are related to the link between sleep movements and motor milestone onset.

Angelina Allia

Angelina Allia is an undergraduate student at the College of Staten Island. Her focus is the impact of motor skill on infant sleep state distributions.

Sarah E. Berger

Sarah Berger is a full professor at the Graduate Center of the City University of New York and College of Staten Island. She is the primary investigator of the Child Development Lab and her research focuses on sleep, motor and cognitive development during infancy.