Norms for Voice, Motor Speech, & Resonance Assessments

Informal speech therapy assessments can provide quick and valuable objective data. But what do you do if they don’t come with norms?

In this post, you’ll find norms for voice, motor speech, and resonance to help you best interpret your assessment results.

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Norms for Voice, Motor Speech, & Resonance Assessments

norms for voice

As appropriate, refer patients who test outside of the norms to ENT.

And don’t forget subjective data! While objective data (like the norms listed below) are great, factor in subjective information too. This will give you a better understanding of how your patient is functioning.

If, for example, your patient’s maximum phonation time is below the norms—but they’re intelligible and not interested in therapy—it may be just fine not to recommend services.

Diadochokinetic Rate (DDK) Norms

Males aged 65 to 74 years

  • Puh: 5.3-7.8
  • Tuh: 5.7-7.3
  • Kuh: 5.0-8.1
  • Puh tuh kuh: 3.0-8.0

Males aged 74-86 years

  • Puh: 5.4-8.1
  • Tuh: 3.6-8.2
  • Kuh: 3.5-7.2
  • Puh tuh kuh: 2.5-9.0

Females aged 65 to 74 years

  • Puh: 5.2-7.5
  • Tuh: 4.0-7.7
  • Kuh: 3.3-7.3
  • Puh tuh kuh: 3.7-7.8

Females aged 74 to 86 years

  • Puh: 4.1-7.6
  • Tuh: 3.9-7.2
  • Kuh: 3.2-6.9
  • Puh tuh kuh: 4.3-6.9

DDK Rates What Else To Look For

DDK rate less than norms: Muscle weakness or discoordination, reduced intelligibility, frustration while speaking

DDK more than norms: Muscle rigidity, reduced intelligibility

Maximum Phonation Time (MPT) Norms

Adult males: Range of 25-35 seconds

Males aged 16 to 64 years : 26 seconds average

Males aged 65 years+: 15 seconds average

Adult females: Range from 15-25 seconds

Females aged 16 to 64 years: 21 seconds average

Females aged 65+ years: 14 seconds average

Max Phonation Time: What Else To Look For

MPT less than norms: reduced breath support for speech, breathiness, reduced intensity, reduced intelligibility

MPT more than norms: muscle tension, strained voice

s/z Ratio Norms

1.4 or above may indicate vocal fold dysfunction

Fundamental Frequency Norms

Older males aged 63 to 86 years: 127 Hz (standard deviation: 27 Hz)

Older females aged 63 to 86 years: 211 Hz (standard deviation: 42 Hz)

Pitch lower than norms: Edema, presbylaryngis (females), infection

Pitch higher than norms: Muscle tension, presbylaryngis (males)

Sound Pressure Level Norms

Older males aged 63 to 86 years: 74.0 dB (standard deviation: 4.6 dB)

Older females aged 63 to 86 years: 74.0 dB (standard deviation: 4.2 dB)

Jitter Norms

Above 0.5% is abnormal voice

Shimmer Norms

5% or above is abnormal voice

Noise To Harmonics Ratio Norms

Above 0.2% is abnormal voice

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  • American Speech-Language-Hearing Association. (n.d.) Practice Portal. Retrieved June 13, 2023.
  • Boersma, P., Weenick, D. (n.d.) Praat: doing Phonetics by Computer. Retrieved June 13, 2023.
  • Goy, H., Fernandes, D.M., Pichora-Fuller, K., & van Lieshout, P. (2013). Normative Voice Data for Younger and Older Adults. Journal of Voice, 27(5), 545-555.
  • Maslan, J., Leng, X., Rees, C., Blalock, D., & Butler, S. G. (2011). Maximum phonation time in healthy older adults. Journal of voice : official journal of the Voice Foundation, 25(6), 709–713.
  • Picheny, M. A., Durlach, N. I., & Braida, L. D. (1986). Speaking clearly for the hard of hearing. II: Acoustic characteristics of clear and conversational speech. Journal of speech and hearing research, 29(4), 434–446.
  • Pierce, John & Cotton, Sue & Perry, Alison. (2013). Alternating and sequential motion rates in older adults. International journal of language & communication disorders / Royal College of Speech & Language Therapists. 48. 257-64. 10.1111/1460-6984.12001. 
  • Wang, Yu-Tsai & Green, Jordan & Nip, Ignatius & Kent, Raymond & Kent, Jane. (2010). Breath Group Analysis for Reading and Spontaneous Speech in Healthy Adults. Folia phoniatrica et logopaedica : official organ of the International Association of Logopedics and Phoniatrics (IALP). 62. 297-302. 10.1159/000316976. 
  • WEVOSYS Medical Technology. (2013). Voice Protocol norms. 
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