1. What is the S/Z Ratio Calculator?

Definition: This calculator determines the ratio between the duration of sustained /s/ and /z/ sounds.

Purpose: It's primarily used in speech pathology and voice assessment to evaluate vocal fold function and airflow.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( \text{S/Z} \) — S/Z ratio (dimensionless)
• \( S_{\text{duration}} \) — Sustained /s/ sound duration (seconds)
• \( Z_{\text{duration}} \) — Sustained /z/ sound duration (seconds)

Explanation: The ratio compares the maximum phonation time for voiceless (/s/) and voiced (/z/) sounds.

3. Importance of S/Z Ratio

Details: A normal S/Z ratio is approximately 1.0. Higher values may indicate vocal fold pathology or glottal insufficiency.

4. Using the Calculator

Tips: Measure the maximum duration the patient can sustain /s/ and /z/ sounds separately, then enter these values in seconds.

5. Frequently Asked Questions (FAQ)

Q1: What does a high S/Z ratio indicate?
A: A ratio significantly greater than 1.0 suggests possible vocal fold pathology or inefficient glottal closure.

Q2: What's considered a normal S/Z ratio?
A: Typically 0.8-1.2 in healthy individuals, though exact norms may vary slightly.

Q3: How should the sounds be produced for testing?
A: The patient should sustain /s/ and /z/ at comfortable pitch and loudness until they can no longer continue.

Q4: What factors can affect the S/Z ratio?
A: Age, respiratory support, vocal fold function, and testing conditions can all influence results.

Q5: Is this test used alone for diagnosis?
A: No, it's typically part of a comprehensive voice evaluation along with other assessments.