## 6 Limitations of the Present Study  
Although we believe that our dataset is robust and that the relationships between OS and LC are strong based on our analyses, there are limitations to this work. First, the speaker sample is relatively small (\(n=20\)) and the representativeness of these speakers may be questioned. It must be noted, however, that we sought to select a group of TE speakers who exhibited a range of voice qualities while at the same time demonstrating good-to-excellent speech intelligibility. Thus, while we attempted to assess a range of TE voice qualities that would not be directly influenced by the listeners' ability to understand the content of the speech signal, changes that may occur in voice quality are likely to further influence assessments of both OS and LC. This concern regarding speakers is, however, somewhat offset by a relatively large listener pool (\(n=51\)) compared with other auditory-perceptual studies reported in the literature. As a general rule, the size of our listener pool is considerably larger than what typically has been reported in the literature for auditory-perceptual evaluations of TE speakers. Both dimensions that were studied in this project were operationally defined for the listeners. Nevertheless, we do believe that the complexities associated with grossly unusual or unnatural voice signals such as those common to those who use TE voice and speech will have additive effects on how such signals are perceived and judged by listeners. More directly, it is currently unknown if there is a key or more prominent component of a TE signal that may carry more significant perceptual \"weight\" relative to judgments of individual speakers. Thus, how any given component of a signal, including changes in frequency and intensity and associated variability (perturbation), the related variations in the relative SNRs and their consistency or inconsistency, alterations in the temporal flow of speech (i.e., speech rate, pause time, linguistic juncture, etc. ), are perceptually summed together must be considered. Currently, there are no data in the literature to suggest that a particular component of a TE voice signal carries more perceptual salience relative to other features that characterize any given sample. Clearly, this type of investigation is worthy of future study. This also raises the question of the potential influence of listener sophistication on the perceptual judgments provided [35] as more experienced listeners may exhibit unique bias relative to their judgments [19; 25; 30; 31]. The other question that may be raised concerning our listener data is related to the fact that the majority of our listeners were women. There is anecdotal evidence to suggest that auditory-perceptual judgments of women and men may not differ for assessments of male TE speakers. However, listener gender must be considered as a relevant potential independent variable when mixed samples that include both male and female speakers are assessed by listeners. This is particularly true for auditory-perceptual judgements that are made with or without prior knowledge of the TE speaker's gender. With an increasing number of women undergoing laryngectomy, such concerns provide a very important area for future study. Finally, and in the context of the prior information and speaker gender, it is critical to note that the present data cannot be generalized to women who undergo TE puncture voice restoration. Although women who are laryngectomized and use TE speech will also exhibit a range of variation that crosses the frequency, intensity, and temporal domains of voice and speech production [30; 31], they also may experience greater levels of social penalty specific to both the OS and LC dimensions. This is of particular importance should the gender of the speaker be identified to the listener [12]. Past research has shown that women TE speakers may incur less positive listener responses and judgments relative to their male counterparts.