Infant Characteristics Interview

Abstract

The Infant Characteristics Interview (ICI), developed by Thomas, Chess, and colleagues in 1963, is a comprehensive parental report method designed to systematically assess and document infant behavior across the first two years of life. This instrument was a foundational component of the New York Longitudinal Study (NYLS), emphasizing careful observation of a child’s responses to novel stimuli and the tracking of consistent behavioral patterns over time. The ICI utilizes a structured yet flexible format, allowing interviewers to delve deeply into various aspects of the child’s life, including family context (siblings), medical history (obstetrical history, the neonatal period), parental responsibilities, and detailed descriptions of daily living routines such as sleep cycles, feeding habits, and crying episodes. Interviews were extensive, typically lasting between one and two hours during the first year and extending to two to four hours in the second year of the child’s life.

Keywords

Infant Characteristics Interview, Parental Report, Infant Development, Behavioral Individuality, Developmental Measures, Test Construction, Child Characteristics, New York Longitudinal Study.

Authors

Thomas, Alexander, Chess, Stella, Birch, Herbert G., Hertzig, Margaret E., Korn, Sam

Purpose

The primary purpose of the Infant Characteristics Interview is to gather rich, detailed qualitative data from parents regarding the behavioral patterns and temperamental attributes of their child during the crucial first twenty-four months of life. It was specifically developed to serve as a standardized, yet adaptable, instrument for capturing the unique behavioral individuality that characterizes early childhood. By focusing on detailed, real-world observations reported by the primary caregiver, the ICI sought to move beyond simple checklists to provide a narrative and contextual understanding of the child’s interactions with their environment and their characteristic style of responding.

Construct

The central construct measured by the Infant Characteristics Interview is Infant Characteristics, which is closely aligned with the concept of temperament. This construct encompasses the stable, observable behavioral styles that infants display in response to internal and external stimuli. The interview structure is designed to elicit information pertaining to several dimensions often associated with temperament, such as:

• Activity Level: The amount of motor activity exhibited.
• Rhythmicity: The predictability and regularity of biological functions (e.g., sleep, hunger).
• Approach/Withdrawal: The nature of the initial response to a new stimulus (e.g., people, objects, situations).
• Adaptability: The ease with which the child adjusts to changes in routine or environment.
• Intensity of Reaction: The energy level of the child’s response, regardless of quality.
• Mood: The amount of pleasant, joyful, and friendly behavior versus unpleasant, crying, and unfriendly behavior.

Validity

Specific quantitative validation studies, such as criterion or construct validity coefficients, were not indicated in the original documentation for the Infant Characteristics Interview. As a foundational instrument utilized primarily in a longitudinal, observational study—the New York Longitudinal Study (NYLS)—the ICI’s strength lies in its comprehensive, qualitative depth rather than its initial psychometric rigor. The validity of the data derived from the ICI is often supported by the convergence of parental reports over time and the detailed nature of the interview protocol, which minimizes reliance on broad generalizations by requiring concrete examples of infant behavior.

The instrument’s utility is often viewed through the lens of ecological validity, ensuring that the observations captured reflect the child’s functioning within their natural environment. However, researchers seeking standard statistical measures of validity should note that such data is not explicitly provided for the ICI itself.

Reliability

No specific reliability data (e.g., internal consistency, test-retest reliability, or inter-rater reliability) was indicated for the Infant Characteristics Interview in the primary source material. Given that the ICI is an extensive, open-ended interview schedule rather than a fixed-item psychometric scale, traditional reliability measures may be challenging to apply directly.

In practice, the reliability of the data collected using the ICI relies heavily on the standardization of the interviewer’s technique and the consistent application of the semi-scheduled questioning framework. The long duration and detailed nature of the interview aim to ensure thorough coverage of the child’s behavior, implicitly enhancing the stability and dependability of the resulting behavioral profile.

Factor Analysis

No explicit factor analysis was indicated for the Infant Characteristics Interview. Since the ICI serves as a data collection guide for parental narratives rather than a quantitative scale composed of discrete, scaled items, a standard factor analysis designed to identify underlying latent variables is not applicable to the instrument itself.

The data derived from the ICI interviews, however, formed the empirical basis upon which the authors of the NYLS later developed their major conceptual categories of temperament. Thus, while the interview guide was not subjected to factor analysis, the behavioral data it yielded was essential for subsequent theoretical and statistical organization of infant characteristics.

Instrument

Test Type: Interview Schedule/Guide

Format: Structured but flexible interview, utilizing semi-scheduled questioning to guide the conversation while allowing for in-depth parental elaboration. The interview duration varies significantly depending on the age of the child and the level of detail provided by the parent (1-2 hours in the first year; 2-4 hours in the second year).

Language Available: English (Original Language)

Population Group: Human

Age Group: The focus populations are Neonatal (birth – 1 month), Infancy (2-23 months), and Preschool Age (2-5 years). The instrument itself is administered to parents.

Population Details: The data collection sample consisted of parents of children aged two years and older, who provided retrospective and ongoing reports of their child’s behavior.

Test Methodology: The methodology is qualitative and observational, relying entirely on the parent’s detailed report of the child’s behavior and responses. No specific psychometric scoring or scaling procedures are provided for the interview guide itself.

Keywords

Parental Perception, Behavioral Observation, Longitudinal Study, Temperament Assessment, Child Development, Neonatal Behavior, Interview Methodology.

Authors

Author ORCID Identifier: Not provided

Affiliation Email addresses: Not provided

Correspondence Address: Correspondence generally directed toward the New York University Press or the authors’ estates, given the historical context of the publication.

Permissions & Fee and Test Year

The Infant Characteristics Interview was first documented in 1963 as part of the seminal work, Behavioral Individuality in Early Childhood. Information regarding current licensing fees or specific permissions required for academic use must be obtained by contacting the current rights holder or the publisher (New York University Press). The original test items are not readily available in the public domain; access requires contacting the publisher.

Reference’s

Thomas, A., Chess, S., Birch, H. G., Hertzig, M. E., & Korn, S. (1963). Data collection. In A. Thomas, S. Chess, H. G. Birch, M. E. Hertzig, & S. Korn, Behavioral individuality in early childhood (pp. 24–34). New York University Press. https://doi.org/10.1037/14328-003

Items of the Infant Characteristics Interview

IMPORTANT: The following scale items must be preserved in their original language and must not be changed in any way.

Test Items Available: No (To access the test items, contact the publisher.)