Abstract
Objective: To find Maximum phonation time (MPT) for normal Pakistani adults falling within the age range of 21-50 years and to examine interactions between trials of MPT, age, and gender.
Methodology: Two-stage sampling was employed. First, convenience sampling was used for approaching suitable participants, followed by purposive sampling. Participants were recruited from the students, staff and faculty of the University of the Punjab, Lahore, Pakistan, their families and the families of the clients consulting to the University Clinic for clinical services.
The subjects were divided into three age groups; 21-30 years, 31-40 years, and 41-50 years. The screening was done for any vocal/laryngeal disorder and only non-smokers or the ones who had quit smoking for more than five years were selected. After demonstrating an abbreviated model of Maximum Phonation Duration (MPD), at least three valid trials were recorded for each participant. Praat software was used for the recording and calculation of MPT. Repeated measures ANOVA was used for exploring MPT, as a function of gender, age, and trials.
Results: Out of 71 subjects, 34 were male and 37 female. Mean age was 33.98.20 years. No significant interactions were found between MPT trials, age, and gender. However, normal values of MPT for each age group and gender were obtained. The MPT values for men were found to be slightly higher as compared to women.
Conclusion: These results may be used as normal data during clinical voice assessment and treatment for Pakistani adults.

Key words: Maximum Phonation Time, MPT, Glottal efficiency, Praat.