Abstract
BACKGROUND: The voice range profile (VRP) is an acoustic measurement in vocal function voice assessment. While several factors influencing VRP outcomes are known, the impact of body posture during VRP recordings remains unexplored. AIMS: To investigate the effects of standing and sitting posture on VRP performance in vocally healthy individuals. METHODS AND PROCEDURES: Thirty vocally healthy and untrained participants were randomised into two groups. Group 1 performed VRP measurements first in a sitting position, followed by standing. Group 2 completed the tasks in reverse order. VRP parameters were compared between sitting and standing positions, and training effects between the first and second measurements were analysed. OUTCOMES AND RESULTS: No significant differences were found in any VRP parameter between sitting and standing positions (all p values > 0.05), with nearly all effect sizes being very small or small. Furthermore, no training effect was observed among the two trials in each group (all p values > 0.05, ICC > 0.75, very small or small effect sizes). CONCLUSIONS AND IMPLICATIONS: Posture (sitting vs. standing) did not significantly influence VRP performance in the first instance when considering people without voice disorders. This might suggest flexibility in patient positioning during VRP assessments, potentially simplifying clinical protocols without compromising data integrity. WHAT THIS PAPER ADDS: What is already known on this subject Voice Range Profile (VRP) is a standard acoustic tool for assessing vocal function influenced by several factors such as recording methods, software, and patient characteristics. Though practical guidelines often recommend performing VRP assessments in a standing position, no empirical evidence has previously evaluated the effect of body posture on VRP outcomes. Thus, the clinical necessity of specific postural instructions during VRP remains unclear. What this paper adds to the existing knowledge This study is the first to investigate how body posture (sitting vs. standing) affects VRP performance in vocally healthy and untrained individuals. Using a randomised crossover design, it found no significant differences in any VRP parameter between sitting and standing conditions. Additionally, there was no observed training effect between repeated measurements, suggesting high test-retest reliability. These findings challenge the assumption that standing is superior for VRP assessments. What are the potential or actual clinical implications for this work? The results suggest that body posture may not substantially influence VRP outcomes in vocally healthy and untrained individuals. Therefore, conducting VRP assessments in either sitting or standing positions could be considered in certain clinical contexts, especially when accommodating patient needs. However, given the study's focus on healthy participants, these findings should be interpreted with caution. Further research involving diverse populations, including individuals with voice disorders or specific postural conditions, is needed before recommending broader changes to clinical protocols.