Maximum Phonation Time of School-Aged Children in Pakistan: A Normative Study

Maximum phonation time (MPT) evaluates maximum vocal capabilities and can be used to assess the effectiveness of behavioral and medical therapy interventions. There is a literature gap regarding MPT normalcy data for Pakistani children. Objective: To determine the Maximum Phonation Time of School Aged Children in Pakistan and its association with participant variables and impact of the 6-minute walk test on participant vitals. Methods: This cross-sectional survey was conducted in Rawalpindi and Islamabad on typical healthy school-aged children from August 2021 to January 2022. The sample included both genders, aged 6-13 years having normal language. Tools used included a basic demographic sheet, token test, stopwatch, growth chart, sphygmomanometer, pulse oximeter, and 6-minute walk test. Blood Pressure, oxygen saturation, heart rate, and MPT were calculated before and after the six-minute walk test (6-MWT). Data were analyzed by using SPSS version 21.0. Results:  Results show MPT of 13.11 ± 3.93 seconds. Scores were significantly (p= 0.000) higher for higher age groups. 6-MWT revealed a significantly (p=0.000) higher post walk SPO2 (99.16 ± 0.89 Vs.97.82 ± 1.45), HR (105.94 ± 14.53 vs 92.94 ± 14.79). systolic (112.46±13.40 vs. 107.25 ± 13.66) and diastolic blood pressure (79.07 ± 8.17 Vs.73.84 ± 8.50) compared to pre walk. A significantly (p<0.001) strong positive correlation was noted for age(r=.515), weight (r=.460), height (r=.491) and distance (r=.281). Conclusions: MPT of Pakistani 6-13 years children is 13.11 ± 3.93 seconds with significantly higher MPT for higher age groups. MPT has a strong positive correlation with age, weight, height and distance and increases after walking. MPT values for boys were slightly higher than for girls.