AUDSLP-582 Research in Speech Language Pathology Courtney Ciulla and Sarah Galloway

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1 AUDSLP-582 Research in Speech Language Pathology Courtney Ciulla and Sarah Galloway The Immediate Effects of Traditional Cigarettes versus Electronic Cigarettes on Measures of Fundamental Frequency Introduction Current research asserts that traditional cigarette smoking is harmful to human health and adversely affects the voice, specifically fundamental frequency (F 0 ). A previous study examining the long-term effects of smoking on voice found that mean F 0 in smokers was significantly lower than in non-smokers, especially in females, due to the tobacco in cigarettes causing edema in the vocal folds. Swelling increased the mass of the vocal folds, lowering F 0 (Gonzalez, 2004). Another long-term study comparing the F 0 of three groups of females (i.e., non-smokers, smokers of less than 10 years, and smokers of more than 10 years) found that female non-smokers had significantly higher F 0 than female smokers (Vincent & Gilbert, 2012). As evidence of the negative effects of traditional cigarette smoking on voice increases, electronic cigarettes have been touted as the "healthy" alternative. However, there is little evidence to support this claim. With minimal research on the effects of e-cigarettes on voice, further research is imperative. The purpose of this study is to compare the immediate effects of traditional smoking and electronic cigarette smoking on measures of fundamental frequency. With p<0.05, there will be no significant difference in fundamental frequency between subjects who receive traditional smoking and e-cigarette smoking as a manipulation ten minutes after smoking and sixty minutes after smoking. Methodology Thirty young adults between the ages of participated in a parametric, randomized, pretest-posttest control group design study. All adults were selected from Bloomsburg University, in good medical standing, and had no prior history of respiratory issues or voice disorders. Participants were post-pubescent and females were pre-menopausal. None of the participants reported smoking (i.e., cigarettes, cigars, hookah, e-cigarettes) prior to the study. The independent attribute variable in this study, group, had three levels, a control group, traditional cigarette group, and e-cigarette group. An overall matching technique was used to equate groups on gender, due to the fact that females typically have a higher F 0 than males (Skuk & Schweinberger, 2014). Matched subjects were randomly assigned to the three groups, with ten subjects per group, to ensure equal probability of assignment. The control group received no manipulation. The traditional and e-cigarette smoking groups were instructed on how to smoke, with duration lasting at most ten minutes. The traditional cigarette group smoked one regular strength Marlboro cigarette with the equivalent of 0.9mg of nicotine. The e-cigarette group smoked the equivalent of one regular strength Marlboro cigarette using the Nemesis "VW" by Atmomixani (Clone) e-cigarette with a CE4 Clearomizer atomizer using 0.9mg of nicotine. A 0.05 ml drop of e-liquid equates to 0.6 mg of nicotine ml of e-liquid was administered to the e-cigarette to equate to 0.9 mg of nicotine, matching the nicotine level in the traditional cigarette (Nicotine Calculations). Measurements of fundamental frequency, a ratio level of measurement, were collected via a voice sample of the Rainbow Passage. Samples were collected in the Bloomsburg University Voice Lab using a calibrated Shure SM58 microphone at a distance of 15 cm from the mouth. The dependent variable of fundamental frequency, a continuous variable, was analyzed using a Multi-Dimensional Voice Program (MDVP) model 4305 from Kay Elemetrics

2 Corporation, implemented in a Computerized Speech Lab (CSL model 4300B, Kay Elemetrics Corp, Pine Brook, New Jersey, USA) (Gonzalez, 2004). The independent categorical variable in this study, time, had three levels, premanipulation, ten minutes post, and sixty minutes post manipulation. A pre-manipulation voice sample was collected from all participants. A second pre-manipulation sample of half of the participants was randomly selected from each of the groups (i.e., 5 from control, 5 from traditional cigarettes, and 5 from e-cigarettes) one week after collecting the initial premanipulation sample. Measures of F 0 during the initial and secondary pre-manipulation sample were compared to establish intra-subject reliability. After collecting the pre-manipulation samples, the smoking manipulations were administered to the traditional and e-cigarettes groups. Voice samples were collected at ten and sixty minutes following administration of the manipulation. Results A paired t-test was conducted on the test-retest pre-manipulation data to determine intrasubject reliability on measurements of F 0. No significant difference was found between the initial and secondary pre-measurements of F 0 (t = 0.56 at p<0.05). A correlational analysis assessed the reliability of the subject s measurements of F 0 between initial and secondary pre-measurements. A Pearson s r test revealed a strong correlation (r= 0.99 at p<.05), verifying that measurements of subject s F 0 were reliable between initial and secondary pre-manipulation measurements. A Two-Way Analysis of Variance (ANOVA) was utilized as there were two independent variables with multiple levels (i.e., between subjects independent variable of group and the within subjects independent variable) and a ratio level of measurement. The results of the ANOVA indicated no significant difference at the.05 level for the main effect of group (f=0.020; df=2,27, p=0.980 at p<0.05), marginal significance for the main effect of time (f=3.01; df=2,54, p=0.057 at p<0.05), and no significant difference for the interaction of group and time (f=0.667, df= 4,54, p=0.667 at p<0.05). A post hoc analysis was not conducted as no significant differences were found. Discussion The results of the ANOVA indicated no significant difference in F 0 between traditional smoking and e-cigarette smoking groups. Therefore, we accepted the null hypothesis. However, marginal significance for time (p=0.06, p<0.05) was found for both traditional cigarettes and e- cigarettes. Previous studies found tobacco from traditional smoking resulted in edema on the vocal folds, increasing mass and reducing F 0 (Gonzalez, 2004). In the present study, immediately after smoking traditional cigarettes and e-cigarettes, F 0 decreased. After sixty minutes, F 0 increased towards pre-manipulation levels. While our findings were only marginally significant, a significant difference may have been found if a larger sample had been utilized. The current study examined 30 individuals. A future study of 60 individuals may provide a more representative sample of the general population, revealing time differences in F 0 post smoking. Additionally, it is possible that a significant difference in F 0 between groups may be found if a long-term study was conducted. Long-term data on the effects of e-cigarette smoking are currently unavailable due to the recent introduction of e-cigarettes to the general population. As data are accumulated, long-term studies may reveal significant differences on the effect of smoking e-cigarettes versus traditional cigarettes on vocal parameters, including F 0. With little evidence supporting current claims that e-cigarettes are the healthier and safer alternative to traditional cigarettes, future research is warranted.

3 References Gonzalez, J., & Carpi, A. (2004). Early effects of smoking on the voice: A multidimensional study. Med Sci Monit, 10(12), CR Retrieved November 20, 2014, from Nicotine Calculations. (n.d.). Retrieved November 18, 2014, from Nicotine-Calulations.html Skuk, V., & Schweinberger, S. (2014). Influences of Fundamental Frequency, Formant Frequencies, Aperiodicity, and Spectrum Level on the Perception of Voice Gender. Journal of Speech, Language and Hearing Research, 57, Retrieved December 4, 2014, from Harvey A. Andruss Library. Vincent, I., & Gilbert, H. (2012). The effects of cigarette smoking on the female voice. Logopedics Phoniatrics Vocology, Retrieved December 3, 2014, from Harvey A. Andruss Library.

4 Data & Graphical Representations Intra-Subject Reliability: Paired T-Test Correlation

5 2-Way ANOVA

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