Goy H, Fernandes DN, Pichora-Fuller MK, van Lieshout P. Normative voice data for younger and older adults. J Voice. 2013;27:545-555.
Voice is a huge area of interest for me. I have been an amateur singer most of my life, but today one of my favorite treatment tasks is helping people with speech and voice disorders communicate more effectively. My contribution for this month’s #Research Tuesday post is a very interesting study that provides normative voice values for both younger and older adults.
The authors collected acoustic voice measures from a large sample of healthy younger and older adults. They selected 159 young adult participants with a mean age of 19.1 (Standard Deviation [SD] +/-1.4) years and 133 older adults with a mean age of 72.0 (SD +/-4.8). Recorded samples were obtained using carefully controlled environment, equipment, procedures, and analysis. Results were compiled, converted to percentiles for ease of clinical application, and ultimately summarized in two separate tables. The table in Appendix 4 of the study presents a comparison of normative values recorded for younger and older males across 17 voice and 3 speech parameters; Appendix 5 presents the same comparison for younger and older females.
Interesting results for the following parameters were noted:
- Fundamental Frequency (F0). Decreased with age in females. Unchanged in males.
- Speaking Fundamental Frequency (SF0). Lower SF0 with aging in females; no difference in males.
- SF0 SD. More variation in SF0 in females vs. males. Variation in females declined with age.
- Perturbation Measures. Males demonstrated age-related changes to shimmer while females did not. Jitter unchanged with aging in either group.
- Noise-to-Harmonics Ratio (NHR) and Harmonics-to-Noise Ratio (HNR). Unremarkable in this study; however, the authors state that previous studies contradict these results and discussed potential reasons for the discrepancy.
- Dysphonia Severity Index (DSI). No significant differences between younger and older males were noted. Older females demonstrated a significantly higher DSI compared to younger females. Mean Phonation Time (MPT) was significantly longer in older females and combined with insignificant differences in the other components of the DSI to contribute to this finding.
This study is a unique comparison of acoustic measures collected from healthy younger and older adults under standardized conditions. Clinically, it may serve as a reference to help identify healthy vs. disordered patterns in aging clients/patients. It provides a wealth of data that may prove useful as a screening tool within my practice.
I like the fact that the results of this study provide a baseline of data collected under ideal clinical conditions. It gives future researchers a reference point from which to measure the viability and comparative accuracy of new technology and clinical techniques.
On the other hand, the authors admit that future research based upon this work should probably be conducted under the same controlled conditions. I am afraid this will preclude important, functional, clinical studies comparing the efficacy of new, more portable technology vs. the stationary “ideal” conditions of a laboratory setting.
For example, I would like very much to see a comparison of data collected via iPad applications designed to collect perturbation measures vs. measures collected under the tightly controlled conditions seen here. These iPad apps are very attractive to mobile therapists who assess and treat in functional settings, e.g. a patient’s home. Unfortunately, such “informal measures” are extremely sensitive to ambient noise and I expect would be difficult to standardize across multiple, varied settings.
Still, the Goy et al. (2013) study provides a very nice foundation. Very interesting article! I recommend it highly.
Cyndee Williams Bowen, Speech-Language Pathologist, owns Bowen Speech-Language Therapy, LLC in Clearwater, FL. She provides quality, creative, collaborative service to help her clients work toward achieving their goals and an improved quality of life. Visit the Bowen Speech Website for more information.