Attention & Processing Speed1–2 minBurden: MediumEMA: Medium

Symbol-Digit Coding

A smartphone adaptation of code substitution that measures processing speed and visual matching.

Processing speedAttention
Category
Attention & Processing Speed
Typical duration
1–2 min
Participant burden
Medium
EMA suitability
Medium

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Include practice trials

Shown with feedback before the main task

Task parameters

The symbol-digit key changes between runs to reduce memorization effects.

1–2 minBurden: MediumEMA: Medium

This is a researcher preview. No participant data is recorded.

Simulated participant view

9:41

Symbol-Digit Coding

A smartphone adaptation of code substitution that measures processing speed and visual matching.

No data is recorded

Participant experience on smartphone

A symbol key at the top, one symbol prompt in the center, and a number keypad below.

When to use

Useful when a study needs a stronger processing-speed task than simple reaction time.

When not to use

Less suitable for very high-frequency sampling if participant burden must be minimal.

How to use in a study

Use one-at-a-time presentation with a visible key and a short timed run.

Researcher-configurable parameters

  • Timed duration
  • Practice enabled / disabled
  • Number of response options
  • Alternate key forms

Outputs collected

  • Correct responses
  • Errors
  • Omissions
  • Response speed

Interpretation notes

Performance may improve with practice, so alternate forms and repeated designs should be planned carefully.

Scientific evidence

  • Smartphone-based SDMT variants show good reliability and practical feasibility.
  • A one-at-a-time keypad-based design fits unsupervised smartphone administration well.

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