{
  "abstract": "Phase angles measured at low frequencies with the tetrapolar technique are sometimes scattered or even positive. We used Monte Carlo simulations of lock-in detection to quantify how large phase errors that measurement noise alone can cause. For a signal-to-noise ratio after demodulation (SNRout) of about 3 or higher, the standard deviation of the phase error was close to 57° divided by SNRout, and 95% of the errors were within about twice this value. At SNRout = 10 the error standard deviation was 6°; at SNRout = 1 it was 64° and 16% of the measurements were wrong by more than 90°. As SNRout decreased towards zero, the phase gradually approached a completely random value. In an illustrative low-frequency tetrapolar measurement, the absolute phase errors were small (standard deviation 0.007° at 1 Hz and 0.04° at 0.1 Hz), but the true tissue phase was even smaller. The error was therefore 1.2 times the true phase at 1 Hz and 37 times at 0.1 Hz, and the measured phase had the wrong sign in 20% and 49% of the measurements, respectively. The sign of a small phase angle is only reliable (wrong in less than 1% of measurements) when the true phase is larger than 2.3 times the error standard deviation.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Physics, University of Oslo, Oslo, Norway",
    "Department of Clinical and Biomedical Engineering, Oslo University Hospital, Oslo, Norway"
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 3,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Jie Hou"
    },
    {
      "affs": [
        0
      ],
      "name": "Sisay Mebre Abie"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Ørjan G. Martinsen"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/19574jz791s21.bib",
  "cited_by": 0,
  "doi": "10.2478/joeb-2026-0017",
  "fulltext_url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC13734696/",
  "id": "19574jz791s21",
  "issns": [
    "1891-5469"
  ],
  "landing_url": "https://doi.org/10.2478/joeb-2026-0017",
  "language": "en",
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "heading",
      "Communication"
    ],
    [
      "lcc",
      "R5-920"
    ],
    [
      "openalex",
      "2208|Electrical and Bioimpedance Tomography"
    ]
  ],
  "openalex": "W7225230720",
  "pdf_url": "https://reference-global.com/download/article/10.2478/joeb-2026-0017.pdf",
  "pmcid": "PMC13734696",
  "pmid": "42985651",
  "published": "2026-10-01",
  "publisher": "De Gruyter",
  "ris": "https://research.draconitic.com/paper/19574jz791s21.ris",
  "sources": [
    {
      "first_seen": "2026-11-08T12:24:07Z",
      "native_id": "PMC13734696",
      "source": "pmc",
      "url": "https://doi.org/10.2478/joeb-2026-0017"
    },
    {
      "first_seen": "2026-11-09T14:21:33Z",
      "native_id": "06c067a8ed704fd0b75f7760c642c7e3",
      "source": "doaj",
      "url": "https://doi.org/10.2478/joeb-2026-0017"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "lcc:R5-920",
      "subfield": "general"
    }
  ],
  "title": "Monte Carlo study of noise-induced phase angle errors in low-frequency tetrapolar bioimpedance measurements",
  "title_text": "Monte Carlo study of noise-induced phase angle errors in low-frequency tetrapolar bioimpedance measurements",
  "type": "peer-reviewed",
  "updated_at": "2026-11-09T14:21:33Z",
  "url": "https://research.draconitic.com/paper/19574jz791s21",
  "venue": "Journal of Electrical Bioimpedance",
  "versions": []
}