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Related Experiment Video

Updated: Jul 6, 2026

Use of a Video Scoring Anchor for Rapid Serial Assessment of Social Communication in Toddlers

Use of a Video Scoring Anchor for Rapid Serial Assessment of Social Communication in Toddlers

Published on: March 14, 2018

Revised Knox Preschool Play Scale: interrater agreement and construct validity.

Milena Jankovich¹, Jacqueline Mullen, Erin Rinear

¹Division of Occupational Therapy, Department of Rehabilitation Medicine, University of Washington, Seattle, USA.

The American Journal of Occupational Therapy : Official Publication of the American Occupational Therapy Association

|April 9, 2008

Summary

The Revised Knox Preschool Play Scale (RKPPS) demonstrates good interrater reliability and construct validity in typically developing children. Raters showed consistent scoring, supporting its use in assessing developmental play progression.

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Area of Science:

Developmental Psychology
Pediatric Assessment
Play Therapy

Background:

The Revised Knox Preschool Play Scale (RKPPS) is a tool used to assess play behaviors in children.
Evaluating the psychometric properties of assessment tools is crucial for their reliable application.

Purpose of the Study:

To examine the interrater agreement of the RKPPS.
To assess the construct validity of the RKPPS.

Main Methods:

Two trained raters observed 38 typically developing children (36-72 months) during two 15-minute free-play sessions.
Scores for overall play age, 4 dimension scores, and 12 category scores were analyzed for agreement.

Main Results:

High interrater agreement was found: overall play age scores were within 8 months 86.8% of the time.
Dimension and category scores showed excellent agreement, ranging from 81.8% to 100%.
Construct validity was supported by a match between chronological ages and RKPPS play age scores.

Conclusions:

The RKPPS demonstrates sufficient interrater consistency for practical use.
The RKPPS scores progress developmentally, supporting its construct validity in assessing preschool children's play.