Background and Aim: Objective measurement is general and acoustic measurements in particular have become a substantial aspect of stuttering assessment during the last few decades. Measurements do not replace the perceptual judgment, but they allow a more precise diagnosis, provide more evidence for therapeutic interventions, and are useful as feedback for patients in therapy. The purpose of this investigation was to compare some adult male stutterers&apos and nonstutterers&apos acoustic features.
Materials and Methods: Adult male stutterers and nonstutterers participated this case-control  study. Their fluent reading of 20 sentences in Farsi, prolongation of  vowels /a/ and /i/, and rhythmic counting from 1 to 20 were analyed with Dr. Speech software.
Results: There were no significant differences between two groups in fundamental frequency (f₀) and standard deviation of f₀ in three speech samples (vowels /a/ and /i/, reading 20 sentences, and rhythmic counting from 1 to 20). No significant difference were between two groups for jitter and shimmer.
Conclusion: Non significant differences between two groups are somewhat due to investigation of this parameters in fluent speech of stutterers  and nonstutterers.

Background and Aim: Vocal cord nodule is one of the voice disorders causes hoarseness and breathy voice. Voice therapy is one of the treatment approaches. We aimed to find out the effects of voice therapy on vocal acoustic characteristics in these patients.
Methods: In this case series, five women with vocal nodule (14 to 45-year-old) participated in a 9-week voice therapy program developed by Boone. Vocal hygiene and voice practices were measured every day using a questionnaire. Moreover, structure and movements of vocal folds were examined using videolaryngostroboscope by a laryngologist before and after voice therapy to evaluate the effectiveness of program. For collecting voice samples we used sustained /æ/ in comfortable loudness for all patients and data were analyzed using Speech Studio.
Results: After voice therapy, fundamental frequency in four of five subjects were decreased but it was not significant (p=0.225). However, jitter in all of five subjects was significantly decreased (p=0.043). After voice therapy, shimmer in three of five subjects were decreased that was not significant (p=0.345).
Conclusion: Voice therapy can be used for the remedy of acoustic vocal characteristics and elimination or contraction of vocal cord nodule.