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Low vs. Standard Dose CT for Appendicitis Trial (LOCAT)

This study is ongoing, but not recruiting participants.
Sponsor:
ClinicalTrials.gov Identifier:
NCT01925014
First Posted: August 19, 2013
Last Update Posted: November 10, 2017
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
Collaborators:
Ministry of Health & Welfare, Korea
Seoul National University Bundang Hospital
Radiology Imaging Network of Korea for Clinical Research
Information provided by (Responsible Party):
Kyoung Ho Lee, MD, Seoul National University Bundang Hospital
  Purpose
To determine whether low-dose (LD) CT is noninferior to standard-dose (SD) computed tomography (CT) as the first-line imaging test in adolescents and young adults in regard to negative appendectomy rate (NAR).

Condition Intervention
Appendicitis Radiation: Diagnostic CT with low-dose radiation Radiation: Diagnostic CT with standard-dose radiation

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double (Participant, Outcomes Assessor)
Primary Purpose: Diagnostic
Official Title: A Multi-institutional Trial Comparing Clinical Outcomes Following Low- vs. Standard-dose Abdominal CT as the First-line Imaging Test in Adolescents and Young Adults With Suspected Acute Appendicitis

Resource links provided by NLM:


Further study details as provided by Kyoung Ho Lee, MD, Seoul National University Bundang Hospital:

Primary Outcome Measures:
  • Negative appendectomy rate [ Time Frame: 1 week after surgery ]
    Negative appendectomy rate is defined as the percentage of negative (unnecessary) appendectomies out of all non-incidental appendectomies. As a secondary analysis, negative appendectomy rate in an alternative definition is calculated by excluding cases with appendiceal neoplasms without superimposed appendicitis, as appendectomy would be clinically necessary in such patients. Any surgery performed for the treatment of presumed appendicitis is counted as non-incidental appendectomy, even though the surgical procedures may be more extensive than simple appendectomy (e.g., ileocectomy).


Secondary Outcome Measures:
  • Appendiceal perforation rate [ Time Frame: 1 week after surgery ]
    The percentage of perforated appendicitis of all confirmed appendicitis cases.

  • Negative appendectomy rate (alternative definition) [ Time Frame: 1 week after surgery ]
    The percentage of negative appendectomies out of all randomized cases.

  • Appendiceal perforation rate (alternative definition) [ Time Frame: 1 week after surgery ]
    The percentage (i.e., prevalence) of perforated appendicitis out of all randomized cases.

  • Prevalence of non-perforated appendicitis [ Time Frame: 1 week after surgery ]
    The percentage (i.e., prevalence) of non-perforated appendicitis out of all randomized cases.

  • Additional Imaging Test(s) [ Time Frame: 1 week after CT ]
    The proportion of patients requiring additional imaging test(s) in order to diagnose or rule out appendicitis.

  • Delay in patient disposition [ Time Frame: 1 day after surgery ]
    • Interval from CT acquisition to appendectomy in patients undergoing non-incidental appendectomy. Interval appendectomies following percutaneous abscess drainage and/or medical treatment are not included in this analysis.
    • Interval from CT acquisition to hospital discharge in patients not undergoing surgery.

  • Hospital stay associated with non-incidental appendectomy [ Time Frame: 3 months after CT ]
    The interval from CT acquisition to hospital discharge after non-incidental appendectomy. Interval appendectomies following percutaneous abscess drainage and/or medical treatment are not included in this analysis.

  • Appendectomy rate [ Time Frame: 3 months after CT ]
    The percentage of appendectomies out of all randomized cases.

  • Diagnostic performance of CT reports [ Time Frame: 3 months after CT ]
    • Area under receiver-operating-characteristic curve.
    • Diagnostic sensitivity and specificity: for calculation of the sensitivity and specificity, the 5-grade likelihood scores for appendicitis are collapsed into binary responses with a decision threshold of a score ≥ 3 as positive for the diagnosis. This decision threshold is based on the fact that appendicitis is actually present in 13-73% of patients with CT scans interpreted as equivocal and that appendiceal perforation as a consequence of a false-negative diagnosis is considered more harmful to patients than a negative appendectomy as a consequence of a false-positive diagnosis.

  • Diagnostic confidence in diagnosing and ruling out appendicitis [ Time Frame: 3 months after CT ]
    • Likelihood score for appendicitis in patients confirmed as having appendicitis.
    • Likelihood score for appendicitis in patients confirmed as not having appendicitis.
    • The frequency of indeterminate CT interpretation (grade 3).
    • The frequency of normal appendix visualization at CT.

  • Diagnosis of appendiceal perforation at CT [ Time Frame: 3 months after CT ]
    • Diagnostic sensitivity: the number of correct detections of the perforation divided by the number of cases of perforated appendicitis.
    • Diagnostic specificity: the number of correct ruling out the perforation divided by the number of cases of appendicitis without perforation.


Estimated Enrollment: 3000
Study Start Date: December 2013
Estimated Study Completion Date: February 2017
Primary Completion Date: December 2016 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Low-dose CT
Diagnostic CT with low-dose radiation
Radiation: Diagnostic CT with low-dose radiation
Effective dose is aimed at approximately 2 millisievert in an average patient.
Other Name: Low-dose CT
Active Comparator: Standard-dose CT
Diagnostic CT with standard-dose radiation
Radiation: Diagnostic CT with standard-dose radiation
Effective dose is aimed at approximately 8 millisievert in an average patient.
Other Name: Standard-dose CT

Detailed Description:
  • Acute appendicitis is a very common disease. Many patients are adolescents or young adults.
  • CT is the current standard imaging test for the diagnosis of appendicitis.
  • In recent years, the awareness of carcinogenic risk associated with CT radiation has increased.
  • According to a recent single-institutional randomized controlled trial, LD CT (employing a quarter of standard radiation dose) was found to be noninferior to SD CT with respect to NARs in adolescents and young adults with suspected appendicitis.
  • However, LD CT is not yet widely accepted.
  • To establish LD CT as the first-line imaging test, a multi-institutional study is needed to confirm the generalizability of the prior single-institutional study.
  Eligibility

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.


Ages Eligible for Study:   15 Years to 44 Years   (Child, Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • Emergency department visit with suspected symptoms and signs of acute appendicitis
  • Intravenous contrast-enhanced computed tomography examination requested due to suspicion of appendicitis
  • Willing to provide telephone or cell phone numbers for follow-up
  • Signed informed consent provided prior to study entry

Exclusion Criteria:

  • Prior cross-sectional imaging tests to evaluate the presenting symptoms and signs
  • Prior history of surgical removal of the appendix
  Contacts and Locations
Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01925014


Locations
Korea, Republic of
Kangwon National University Hospital
Chuncheon, Gangwon, Korea, Republic of, 200-722
Korea University Ansan Hospital
Ansan, Gyeonggi, Korea, Republic of, 425-707
Hallym University Sacred Heart Hospital
Anyang, Gyeonggi, Korea, Republic of, 431-070
Soonchunhyang University Bucheon Hospital
Bucheon, Gyeonggi, Korea, Republic of, 420-767
Seoul National University Bundang Hospital
Seongnam, Gyeonggi, Korea, Republic of, 463-707
Daejin Medical Center, Bundang Jesaeng General Hospital
Seongnam, Gyeonggi, Korea, Republic of, 463-774
Keimyung University Dongsan Medical Center
Daegu, Korea, Republic of, 700-712
Chonnam National University Hospital
Gwangju, Korea, Republic of, 501-757
Wonkwang University Sanbon Hospital
Gyeonggi, Korea, Republic of, 435-040
Wonkwang University School of Medicine & Hospital
Iksan, Korea, Republic of, 570-711
Gachon University Gil Medical Center
Incheon, Korea, Republic of, 405-760
Jeju National University Hospital
Jeju, Korea, Republic of, 690-767
Seoul National University Hospital
Seoul, Korea, Republic of, 110-744
Kangbuk Samsung Hospital
Seoul, Korea, Republic of, 110-746
Severance Hospital
Seoul, Korea, Republic of, 120-752
The Catholic University of Korea, College of Medicine, Seoul St. Mary's Hospital
Seoul, Korea, Republic of, 137-701
Soonchunhyang University Seoul Hospital
Seoul, Korea, Republic of, 140-887
Hallym University Kangnam Sacred Heart Hospital
Seoul, Korea, Republic of, 150-950
Korea University Guro Hospital
Seoul, Korea, Republic of, 152-703
Chung-Ang University Hospital
Seoul, Korea, Republic of, 156-755
Sponsors and Collaborators
Kyoung Ho Lee, MD
Ministry of Health & Welfare, Korea
Seoul National University Bundang Hospital
Radiology Imaging Network of Korea for Clinical Research
Investigators
Study Chair: Kyoung Ho Lee, MD Seoul National University Bundang Hospital
Study Director: Kyuseok Kim, MD Seoul National University Bundang Hospital
  More Information

Publications:
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Kyoung Ho Lee, MD, Professor, Seoul National University Bundang Hospital
ClinicalTrials.gov Identifier: NCT01925014     History of Changes
Other Study ID Numbers: LOCAT
First Submitted: August 15, 2013
First Posted: August 19, 2013
Last Update Posted: November 10, 2017
Last Verified: January 2017
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: Undecided

Keywords provided by Kyoung Ho Lee, MD, Seoul National University Bundang Hospital:
Appendectomy
Appendicitis
False Positive Reactions
Humans
Radiation Dosage
Tomography, X-Ray Computed
Young Adult

Additional relevant MeSH terms:
Appendicitis
Intraabdominal Infections
Infection
Gastroenteritis
Gastrointestinal Diseases
Digestive System Diseases
Cecal Diseases
Intestinal Diseases