Obesity, Morbid4XLNCT00923819
4XL Study - Obesity Surgery in Adolescence
A study testing Laparoscopic gastric bypass and Standard conservative treatment in people with Obesity, Morbid, run by Sykehuset i Vestfold HF at 1 site in Norway.
Trial summary
The purpose of this study on adolescents between 13 and 18 years of age with morbid obesity is to determine whether surgical treatment gives more health benefits than standard conservative treatment, and if laparoscopic gastric bypass is a method with high safety and a low complication rate. Read more about this study
- Who is it for?
- Ages 13 to 18 years
- Conditions the study is for
- Obesity, Morbid
- What is being tested?
- Laparoscopic gastric bypass and Standard conservative treatment
- Type of treatment
- Surgery or procedure, Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 120 participants
- Where
- 1 siteNorway
- Study dates
- Jun 2009to Dec 2035
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 13 to 18 years
- All sexes
- No healthy volunteers
- Child, Adult
Who may be able to join
- Between 13 and 18 years of age at inclusion
- Tanner stage 4-5
- BMI > 40 kg/m2 or BMI > 35 with at least one comorbidity (type 2-diabetes, obstructive sleep apnea, serious hypertension or cerebral pseudotumor)
- At least one year multidisciplinary treatment completed
Who cannot join
- Tanner stage < 4
- Substantial risk for lack of compliance
- Obesity syndrome (e.g., Prader Willi syndrome)
- Obesity related to brain damage
- Serious general disease
- Monogenic obesity
Trial locations and contacts
1 site in 1 country.
Norway1 site
Morbid Obesity Center, The Hospital of Vestfold, South-Eastern Norway Regional Health Authority
Tønsberg, 3103
About this study
Official title: 4XL-Study - Obesity Surgery in Adolescence
The purpose of this study on adolescents between 13 and 18 years of age with morbid obesity is to determine whether surgical treatment gives more health benefits than standard conservative treatment, and if laparoscopic gastric bypass is a method with high safety and a low complication rate.
Read the detailed description
The study has two intervention arms:
Experimental: Group A Surgery; laparoscopic gastric bypass
Active comparator: Group B Patients from Child Obesity Registry of Vestfold who get standard conservative treatment in a multidisiplinary team at Morbid Obesity Center.
All patients are referred to Morbid Obesity Center from other hospitals or general practionairs in Norway. The procedure will take place at the Vestfold Hospital Trust The participants are included for 2 years follow-up with visits to a multidisciplinary team every 3rd month at the Morbid Obesity Center. Total follow-up time is ten years.
- Conditions
- Obesity, Morbid
- Being tested
- Laparoscopic gastric bypass, Standard conservative treatment
- Keywords
- Adolescents, Gastric Bypass, Quality of Life, Mental Health, Lifestyle
- Medical subject headings
- Obesity, Morbid, Psychological Well-Being
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Laparoscopic gastric bypassProcedure or surgery
Patients are referred to Morbid Obesity Center from Vestfold Hospital Trust and other hospitals in Norway. The procedure will take place at Morbid Obesity Center, Vestfold Hospital Trust.
Standard conservative treatmentBehavioural
Participants from Child Obesity Registry who undergoes conservative treatment at Morbid Obesity Center, Vestfold Hospital Trust.
| Study group | Role | What they receive |
|---|---|---|
| Group A | Experimental | Laparoscopic Gastric Bypass Receives: Procedure: Laparoscopic gastric bypass |
| Group B | Active comparator | Standard conservative treatment. Patients from Child Obesity Registry of Vestfold. Receives: Behavioral: Standard conservative treatment |
What is being measured
The primary outcome is the main question the study is designed to answer.
BMI and weight loss
Surgical or standard conservative treatment
Measured: Baseline, Year 1, 2, 5, 10
Secondary outcomes (6)
Quality of Life (KINDL)
Web-based questionnaire baseline and after 1, 2, 5 and 10 years.
Measured: 10 years
Eating Disorders (Child Eating Behavior Questionnaire)
Web-based questionnaire baseline and after 1, 2, 5 and 10 years.
Measured: 10 years
Mental Health (Development and Well-Being Assessment, DAWBA)
Web-based questionnaire baseline and after 1, 2, 5 and 10 years.
Measured: 10 years
Self-Esteem (Rosenberg Self-Esteem scale)
Web-based questionnaire baseline and after 1, 2, 5 and 10 years.
Measured: 10 years
Surgical and Medical Complications
Web-based questionnaire baseline and after 1, 2, 5 and 10 years.
Measured: 10 years
Blood sample results
Blood tests are biobanked at baseline and after 1, 2, 5 and 10 years.
Measured: 10 years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted18 Jun 2009 (estimated)
- Study startJun 2009
- Primary completionAug 2033 (estimated)
- Study completionDec 2035 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Obesity, MorbidStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 120 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Sykehuset i Vestfold HF
- Sponsor type
- University, hospital or other
- Collaborators
- The Hospital of Vestfold
- Responsible party
- Principal investigator, Jøran Hjelmesæth, Sykehuset i Vestfold HF
- Investigators
- Samira Lekhal, PhD,MD, Principal investigator, Vestfold Hospital Trust/The Hospital of VestfoldJøran Hjelmesæth, MD, PhD, Study chair, Vestfold Hospital Trust/The Hospital of Vestfold
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT00923819
- Sponsor's protocol ID
- 4XL-2009
- Acronym
- 4XL
- Status last verified
- Mar 2026
- First submitted
- 17 Jun 2009
- Last updated
- 24 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
Study at a glance
From the registry record, last updated by the sponsor on 24 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- 4XL-Study - Obesity Surgery in Adolescence
- ClinicalTrials.gov ID
- NCT00923819
- Acronym / sponsor ID
- 4XL / 4XL-2009
- Conditions
- Obesity, Morbid
- Keywords
- Adolescents, Gastric Bypass, Quality of Life, Mental Health, Lifestyle
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 120 participants (estimated)
- Lead sponsor
- Sykehuset i Vestfold HFUniversity, hospital or other
- Collaborators
- The Hospital of Vestfold
- Study start
- Jun 2009 (actual)
- Primary completion
- Aug 2033 (estimated)
- Study completion
- Dec 2035 (estimated)
- First posted
- 18 Jun 2009 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this study on adolescents between 13 and 18 years of age with morbid obesity is to determine whether surgical treatment gives more health benefits than standard conservative treatment, and if laparoscopic gastric bypass is a method with high safety and a low complication rate.
Detailed description
The study has two intervention arms:
Experimental: Group A Surgery; laparoscopic gastric bypass
Active comparator: Group B Patients from Child Obesity Registry of Vestfold who get standard conservative treatment in a multidisiplinary team at Morbid Obesity Center.
All patients are referred to Morbid Obesity Center from other hospitals or general practionairs in Norway. The procedure will take place at the Vestfold Hospital Trust The participants are included for 2 years follow-up with visits to a multidisciplinary team every 3rd month at the Morbid Obesity Center. Total follow-up time is ten years.
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Group A | Experimental | Procedure: Laparoscopic gastric bypassLaparoscopic Gastric Bypass |
| Group B | Active comparator | Behavioral: Standard conservative treatmentStandard conservative treatment. Patients from Child Obesity Registry of Vestfold. |
Who may qualify
- Ages
- 13 to 18 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult
Key inclusion criteria (4 listed)
- Between 13 and 18 years of age at inclusion
- Tanner stage 4-5
- BMI > 40 kg/m2 or BMI > 35 with at least one comorbidity (type 2-diabetes, obstructive sleep apnea, serious hypertension or cerebral pseudotumor)
- At least one year multidisciplinary treatment completed
Key exclusion criteria (6 listed)
- Tanner stage < 4
- Substantial risk for lack of compliance
- Obesity syndrome (e.g., Prader Willi syndrome)
- Obesity related to brain damage
- Serious general disease
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Laparoscopic gastric bypassPatients are referred to Morbid Obesity Center from Vestfold Hospital Trust and other hospitals in Norway. The procedure will take place at Morbid Obesity Center, Vestfold Hospital Trust. | Procedure or surgery | Group A |
| Standard conservative treatmentParticipants from Child Obesity Registry who undergoes conservative treatment at Morbid Obesity Center, Vestfold Hospital Trust. | Behavioural | Group B |
Primary outcome
BMI and weight loss
Time frame: Baseline, Year 1, 2, 5, 10
Surgical or standard conservative treatment
6 secondary outcomes
Quality of Life (KINDL)
Time frame: 10 years
Eating Disorders (Child Eating Behavior Questionnaire)
Time frame: 10 years
Mental Health (Development and Well-Being Assessment, DAWBA)
Time frame: 10 years
Self-Esteem (Rosenberg Self-Esteem scale)
Time frame: 10 years
Surgical and Medical Complications
Time frame: 10 years
Blood sample results
Time frame: 10 years
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 24 Apr 2026.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Samira Lekhal, PhD,MD principal investigator
Vestfold Hospital Trust/The Hospital of Vestfold
Jøran Hjelmesæth, MD, PhD study chair
Vestfold Hospital Trust/The Hospital of Vestfold
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Laparoscopic gastric bypass and Standard conservative treatment in people with Obesity, Morbid, run by Sykehuset i Vestfold HF at 1 site in Norway.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 24 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Norway. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
BMI and weight loss (time frame: Baseline, Year 1, 2, 5, 10). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 24 Apr 2026.