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<article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" article-type="research-article">
<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">JDS</journal-id>
<journal-title-group><journal-title>Journal of Data Science</journal-title></journal-title-group>
<issn pub-type="epub">1683-8602</issn><issn pub-type="ppub">1680-743X</issn><issn-l>1680-743X</issn-l>
<publisher>
<publisher-name>School of Statistics, Renmin University of China</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="publisher-id">JDS1103</article-id>
<article-id pub-id-type="doi">10.6339/23-JDS1103</article-id>
<article-categories><subj-group subj-group-type="heading">
<subject>Data Science in Action</subject></subj-group></article-categories>
<title-group>
<article-title>A Video Segmentation Pipeline for Assessing Changes in Pupil Response to Light After Cannabis Consumption</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name><surname>Steinhart</surname><given-names>Benjamin</given-names></name><xref ref-type="aff" rid="j_jds1103_aff_001">1</xref>
</contrib>
<contrib contrib-type="author">
<name><surname>Brooks-Russell</surname><given-names>Ashley</given-names><suffix>PhD</suffix></name><xref ref-type="aff" rid="j_jds1103_aff_002">2</xref>
</contrib>
<contrib contrib-type="author">
<name><surname>Kosnett</surname><given-names>Michael J.</given-names><suffix>MD, MPH</suffix></name><xref ref-type="aff" rid="j_jds1103_aff_003">3</xref><xref ref-type="aff" rid="j_jds1103_aff_004">4</xref>
</contrib>
<contrib contrib-type="author">
<name><surname>Subramanian</surname><given-names>Prem S.</given-names><suffix>MD, PhD</suffix></name><xref ref-type="aff" rid="j_jds1103_aff_005">5</xref><xref ref-type="aff" rid="j_jds1103_aff_006">6</xref>
</contrib>
<contrib contrib-type="author">
<name><surname>Wrobel</surname><given-names>Julia</given-names><suffix>PhD</suffix></name><email xlink:href="mailto:julia.wrobel@cuanschutz.edu">julia.wrobel@cuanschutz.edu</email><xref ref-type="aff" rid="j_jds1103_aff_001">1</xref><xref ref-type="corresp" rid="cor1">∗</xref>
</contrib>
<aff id="j_jds1103_aff_001"><label>1</label>Department of Biostatistics and Informatics, Colorado School of Public Health, <institution>University of Colorado Anschutz Medical Campus</institution>, Aurora, Colorado, <country>USA</country></aff>
<aff id="j_jds1103_aff_002"><label>2</label>Injury and Violence Prevention Center, Colorado School of Public Health, <institution>University of Colorado Anschutz Medical Campus</institution>, Aurora, Colorado, <country>USA</country></aff>
<aff id="j_jds1103_aff_003"><label>3</label>Department of Medicine, CU School of Medicine, <institution>University of Colorado Anschutz Medical Campus</institution>, Aurora, Colorado, <country>USA</country></aff>
<aff id="j_jds1103_aff_004"><label>4</label>Department of Environmental and Occupational Health, Colorado School of Public Health, University of Colorado <institution>Anschutz Medical Campus, Aurora, Colorado</institution>, <country>USA</country></aff>
<aff id="j_jds1103_aff_005"><label>5</label>Departments of Ophthalmology, Neurology, and Neurosurgery, Sue Anschutz-Rodgers Eye Center, CU School of Medicine, <institution>University of Colorado Anschutz Medical Campus</institution>, Aurora, Colorado, <country>USA</country></aff>
<aff id="j_jds1103_aff_006"><label>6</label>Department of Surgery, <institution>Uniformed Services University of the Health Sciences</institution>, Bethesda, Maryland, <country>USA</country></aff>
</contrib-group>
<author-notes>
<corresp id="cor1"><label>∗</label>Corresponding author. Email: <ext-link ext-link-type="uri" xlink:href="mailto:julia.wrobel@cuanschutz.edu">julia.wrobel@cuanschutz.edu</ext-link>.</corresp>
</author-notes>
<pub-date pub-type="ppub"><year>2024</year></pub-date><pub-date pub-type="epub"><day>20</day><month>6</month><year>2023</year></pub-date><volume>22</volume><issue>1</issue><fpage>138</fpage><lpage>151</lpage><supplementary-material id="S1" content-type="archive" xlink:href="jds1103_s001.zip" mimetype="application" mime-subtype="x-zip-compressed">
<caption>
<title>Supplementary Material</title>
<p>The supplementary materials contain a zipped folder with that is also available on GitHub at <uri>https://github.com/benjamin643/pupil_segmentation_and_analysis</uri>. This folder contains code to reproduce all analyses in this paper, one example video, and data for reproducing all results post pupil segmentation.</p>
</caption>
</supplementary-material><history><date date-type="received"><day>10</day><month>2</month><year>2023</year></date><date date-type="accepted"><day>2</day><month>5</month><year>2023</year></date></history>
<permissions><copyright-statement>2024 The Author(s). Published by the School of Statistics and the Center for Applied Statistics, Renmin University of China.</copyright-statement><copyright-year>2024</copyright-year>
<license license-type="open-access" xlink:href="https://creativecommons.org/licenses/by/4.0/">
<license-p>Open access article under the <ext-link ext-link-type="uri" xlink:href="https://creativecommons.org/licenses/by/4.0/">CC BY</ext-link> license.</license-p></license></permissions>
<abstract>
<p>Due to long-standing federal restrictions on cannabis-related research, the implications of cannabis legalization on traffic and occupational safety are understudied. Accordingly, there is a need for objective and validated measures of acute cannabis impairment that may be applied in public safety and occupational settings. Pupillary response to light may offer an avenue for detection that outperforms typical sobriety tests and tetrahydrocannabinol concentrations. We developed a video processing and analysis pipeline that extracts pupil sizes during a light stimulus test administered with goggles utilizing infrared videography. The analysis compared pupil size trajectories in response to a light for those with occasional, daily, and no cannabis use before and after smoking. Pupils were segmented using a combination of image pre-processing techniques and segmentation algorithms which were validated using manually segmented data and found to achieve 99% precision and 94% F-score. Features extracted from the pupil size trajectories captured pupil constriction and rebound dilation and were analyzed using generalized estimating equations. We find that acute cannabis use results in less pupil constriction and slower pupil rebound dilation in the light stimulus test.</p>
</abstract>
<kwd-group>
<label>Keywords</label>
<kwd>image processing</kwd>
<kwd>marijuana impairment</kwd>
<kwd>quantile GAMS</kwd>
<kwd>time series data cleaning</kwd>
</kwd-group>
<funding-group><award-group><funding-source xlink:href="https://doi.org/10.13039/100007590">Colorado Department of Public Health and Environment</funding-source></award-group><award-group><funding-source xlink:href="https://doi.org/10.13039/100000002">National Institutes of Health</funding-source><award-id>R01 DA049800</award-id></award-group><funding-statement>The authors gratefully acknowledge the Colorado Department of Public Health and Environment (Co-PI: Brooks-Russell, Kosnett) and the National Institutes of Health (R01 DA049800). </funding-statement></funding-group>
</article-meta>
</front>
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