Are Children Performing Better on the Digit Span Backward Task Than the Digit Span Forward Task? An Exploratory...

Area of Science:

• Speech-language pathology
• Child development
• Cognitive assessment

Background:

• Community speech-language pathologists (SLPs) observe unexpected higher performance on Digit Span Backward than Digit Span Forward tasks.
• This pattern on the Test of Integrated Language and Literacy Skills (TILLS) requires interpretation guidance for clinicians.

Purpose of the Study:

• To conduct an exploratory analysis of digit span performance patterns in children.
• To provide insights for speech-language pathologists interpreting Digit Span Forward and Backward subtest results on the TILLS.

Main Methods:

• Analysis of Digit Span Forward and Backward subtest performance in the TILLS normative sample (N=1,262).
• Systematic comparison of raw scores, standard scores, and percentile ranks.
• Estimation of span length for 69 participants and evaluation of its relation to performance.

Main Results:

• Higher performance on backward digit span compared to forward digit span was infrequent.
• Observed patterns are attributable to statistical phenomena, comparison of score types (standard scores/percentile ranks vs. raw scores/span length), and the relationship between backward and forward span lengths.
• Better backward scores do not necessarily indicate a longer forward span length.

Conclusions:

• The perception of frequent backward span superiority is likely due to reporting biases for more remarkable findings.
• Clinicians are cautioned against overinterpreting Digit Span Forward and Backward performance differences.
• Understanding score interpretation is crucial for accurate assessment of working memory in children.