Utility of Smart Phones as a Voice Acquisition Device for Assessing Pre and Post Treatment Voice Using PRAAT

Voice assessment before and after treatment helps the clinician to assess the effectiveness of the treatment given and facilitates comparison between different treatment modalities. Voice handicap index -10(VHI-10) questionnaire is a tool which allows the voice to be evaluated subjectively from the patient’s perspective. PRAAT is a freely available, software programme that acoustically analyse voice signals. Smart phones are widely used and the high quality of the embedded microphone in it makes it a suitable and easily available voice recording device. This study aims at using PRAAT and VHI-10 questionnaire in evaluating voice before and after treatment. The utility of smart phones as a voice acquisition device is also explored in the study. Prospective, observational study, carried out from 1st November 2019 to 30th September 2021in the ENT out- patient department at a tertiary hospital in Punjab. 58 patients complaining of dysphonia were enrolled consecutively in the study. All patients underwent detailed history, examination of the larynx using 70-degree rigid laryngoscope. The voice handicap was scored by (VHI-10) questionnaire and acoustic evaluation of voice was done using the PRAAT software. Patients’ voice was further evaluated 3 months post-therapy with VHI 10 questionnaire and acoustic analysis. The parameters measured on PRAAT were mean pitch, jitter (local), shimmer (local), and mean harmonics to noise ratio (HNR). The voice was recorded using a smart phone and later transferred onto a laptop for analysis. The pre and post treatment acoustic parameters and VHI-10 scores were compared and correlated. There was significant difference (p < 0.001) between the pre and post treatment VHI-10 scores and all the acoustic parameters measured except for median pitch (p = 0.995). A poor positive correlation was found between the pre treatment VHI-10 scores and jitter(r = 0.188, p = 0.157) and shimmer (r = 0.288, p = 0.028) values. A negative correlation was observed between pre treatment VHI-10 scores and pitch (r = − 0.151, p = 0.259) and HNR(r = − 0.424, p = 0.001). Post treatment VHI-10 scores showed positive correlation with jitter (r = 0.302, p = 0.021) and shimmer (0.162, p = 0.225) values and negative correlation with pitch (r = − 0.10, p = 0.457) and HNR (r = − 0.356, p = 0.006) values. We found significant differences in the VHI-10 scores and PRAAT voice analysis results before and after treatment in patients complaining with voice change (dysphonia). VHI-10 questionnaire and PRAAT are good and convenient tools for assessing the voice subjectively and objectively. Only a poor to fair correlation was found between VHI-10 scores and PRAAT analysis results. More studies must be done to confirm the utility of smart phones as a voice acquisition device and PRAAT software in voice analysis.