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It has been shown to be advantageous for the ambulatory monitoring of vocal function, specifically in the use of high-order statistics to understand long-term vocal behavior. However, during long-term ambulatory recordings over several days, conditions may drift from the laboratory environment where the IBIF parameters were initially estimated due to sensor positioning, skin attachment, or temperature, among other factors. Observation uncertainties and model mismatch may result in significant deviations in the glottal airflow estimates; unfortunately, they are very difficult to quantify in ambulatory conditions due to a lack of a reference signal. To address this issue, we propose a Kalman filter implementation of the IBIF filter, which allows for both estimating the model uncertainty and adapting the airflow estimates to correct for signal deviations. One-way analysis of variance (ANOVA) results from laboratory experiments using the Rainbow Passage indicate an improvement using the modified Kalman filter on amplitude-based measures for phonotraumatic vocal hyperfunction (PVH) subjects compared to the standard IBIF; the latter showing a statistically difference (p-value =0.02, F=4.1) with respect to a reference glottal volume velocity signal estimated from a single notch filter used here as ground-truth in this work. In contrast, maximum flow declination rates from subjects with vocal phonotrauma exhibit a small but statistically difference between the ground-truth signal and the modified Kalman filter when using one-way ANOVA (p-value =0.04, F=3.3). Other measures did not have significant differences with either the modified Kalman filter or IBIF compared to ground-truth, with the exception of H1-H2, whose performance deteriorates for both methods. Overall, both methods (modified Kalman filter and IBIF) show similar glottal airflow measures, with the advantage of the modified Kalman filter to improve amplitude estimation. Moreover, Kalman filter deviations from the IBIF output airflow might suggest a better representation of some fine details in the ground-truth glottal airflow signal. Other applications may take more advantage from the adaptation offered by the modified Kalman filter implementation.<\/jats:p>","DOI":"10.3390\/app12010401","type":"journal-article","created":{"date-parts":[[2022,1,3]],"date-time":"2022-01-03T22:51:50Z","timestamp":1641250310000},"page":"401","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Kalman Filter Implementation of Subglottal Impedance-Based Inverse Filtering to Estimate Glottal Airflow during Phonation"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4346-2489","authenticated-orcid":false,"given":"Juan P.","family":"Cort\u00e9s","sequence":"first","affiliation":[{"name":"Department of Electronic Engineering, Universidad T\u00e9cnica Federico Santa Mar\u00eda, Valparaiso 2390123, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gabriel A.","family":"Alzamendi","sequence":"additional","affiliation":[{"name":"Institute for Research and Development on Bioengineering and Bioinformatics, Consejo Nacional de Investigaciones Cient\u00edficas y T\u00e9cnicas\u2013Universidad Nacional de Entre R\u00edos, Oro Verde 3100, Argentina"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1486-7003","authenticated-orcid":false,"given":"Alejandro J.","family":"Weinstein","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Universidad de Valpara\u00edso, Valparaiso 2362905, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9373-7065","authenticated-orcid":false,"given":"Juan I.","family":"Yuz","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, Universidad T\u00e9cnica Federico Santa Mar\u00eda, Valparaiso 2390123, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"V\u00edctor M.","family":"Espinoza","sequence":"additional","affiliation":[{"name":"Department of Sound, Universidad de Chile, Santiago 8340380, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6535-573X","authenticated-orcid":false,"given":"Daryush D.","family":"Mehta","sequence":"additional","affiliation":[{"name":"Massachusetts General Hospital, Boston, MA 02114, USA"},{"name":"Speech and Hearing Bioscience and Technology Program, Harvard Medical School, Boston, MA 02115, USA"},{"name":"MGH Institute of Health Professions, Boston, MA 02129, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert E.","family":"Hillman","sequence":"additional","affiliation":[{"name":"Massachusetts General Hospital, Boston, MA 02114, USA"},{"name":"Speech and Hearing Bioscience and Technology Program, Harvard Medical School, Boston, MA 02115, USA"},{"name":"MGH Institute of Health Professions, Boston, MA 02129, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5581-4392","authenticated-orcid":false,"given":"Mat\u00edas","family":"Za\u00f1artu","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, Universidad T\u00e9cnica Federico Santa Mar\u00eda, Valparaiso 2390123, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2359","DOI":"10.1002\/lary.24740","article-title":"The prevalence of voice problems among adults in the United States","volume":"124","author":"Bhattacharyya","year":"2014","journal-title":"Laryngoscope"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"424","DOI":"10.1016\/S0892-1997(01)00043-1","article-title":"Shifts in Relative Prevalence of Laryngeal Pathology in a Treatment-Seeking Population","volume":"15","author":"Coyle","year":"2001","journal-title":"J. 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