Chiari Malformation Type INCT07818122
Health-related Quality of Life in Chiari Malformation Type 1 - A National Cross-Sectional Patient Survey
An observational study of Chiari Malformation Type I, run by Karolinska Institutet at 1 site in Sweden.
Trial summary
The goal of this observational survey study is to investigate factors that may affect the health-related quality of life (HRQoL) in adults with Chiari malformation type 1 (CM1). The main questions it aims to answer are: How do CM1 patients rate their HRQoL compared to the general population? Are there any factors that… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Chiari Malformation Type I
- How many people
- 1,004 participants
- Where
- 1 siteSweden
- Study dates
- 12 Aug 2026to Dec 2026
- Phase
- Observational
- 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 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: The study population consists of adult patients with Chiari malformation type 1 (CM1) identified through the Swedish National Patient Register, which contains nationwide information on inpatient and specialized outpatient care. To ensure diagnostic validity, non-operated patients were included only if they have a documented evaluation at a neurosurgical unit. Operated patients were identified through procedure codes recorded in the register.
Who may be able to join
- diagnosis of Arnold Chiari Malformation (ICD-code Q07.0)
- for operated patients: record of posterior fossa decompression (procedure code ABE50)
- for non-operated patients: the diagnosis Q07.0 recorded during an outpatient visit to a neurosurgical unit
Who cannot join
- record of spina bifida diagnosis (Q05.X)
- for non-operated patients: record of the procedures duraplasty (procedure code AAK10) or another operation on the cranium or dura (procedure code AAK99)
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Sweden1 site
Department of Clinical Neuroscience, Karolinska Institutet
Stockholm
About this study
The goal of this observational survey study is to investigate factors that may affect the health-related quality of life (HRQoL) in adults with Chiari malformation type 1 (CM1). The main questions it aims to answer are:
How do CM1 patients rate their HRQoL compared to the general population? Are there any factors that lead to better or worse HRQoL in CM1 patients? Is there a difference in HRQoL in operated versus non-operated CM1 patients?
Participants will be identified via the Swedish National Board of Health and Welfare's Patient register. They will be asked to participate in a survey of HRQoL containing standardized questionnaires, and their answers will be analyzed together with data from the Patient register. Their questionnaire answers will also be compared to normative Swedish data.
Read the detailed description
This is an observational, cross-sectional survey study investigating health-related quality of life (HRQoL) in adults with Chiari malformation type 1 (CM1).
A total of 1,004 adults with CM1 will be invited to participate, including 666 patients who have undergone surgery for CM1 and 338 patients who have not. Participants were identified through the Swedish National Board of Health and Welfare's National Patient Register, which holds data on all inpatient episodes as well as specialized outpatient visits in Sweden.
Operated patients were identified based on diagnosis of Arnold Chiari Malformation (ICD-code Q07.0) and posterior fossa decompression (procedure code ABE50) recorded in the National Patient Register between 2011 and 2024. Non-operated patients were identified based on a diagnosis of CM1 (ICD-10 code Q07.0) recorded during a visit to a neurosurgical outpatient clinic between 2021 and 2024. Patients with a diagnosis of spina bifida (ICD-10 code Q05.X) were excluded from the overall cohort. Non-operated patients with a record of duraplasty (procedure code AAK10) or another operation on the cranium or dura (procedure code AAK99) were excluded.
Participants will be contacted by mail and invited to complete an online survey administered through REDCap, hosted by Karolinska Institutet. The survey includes the Swedish version of the EQ-5D-3L, including the EQ Visual Analogue Scale (EQ-VAS), the Hospital Anxiety and Depression Scale (HADS), and a study-specific questionnaire focusing on clinical characteristics, medication use, sick leave, return to work, and attitudes toward surgical treatment.
Survey data will be linked to relevant information from the National Patient Register and the Swedish Social Insurance Agency. Register data will include information on diagnoses, surgical treatment, comorbidities, and relevant social insurance variables.
The primary outcomes are HRQoL measured using the EQ-5D-3L index score and EQ-VAS score. HRQoL will be compared with normative data collected from a general population in Stockholm, Sweden. HRQoL and associated factors will also be compared between operated and non-operated participants.
A priori power calculations indicated that, assuming a clinically relevant difference of 0.10 in EQ-5D index score, a standard deviation of 0.25, and a two-sided α of 0.05, responses from approximately 22% of the study population would be sufficient to achieve 80% power. Since the expected response rate is 30-50%, approximately 1,000 patients were chosen to ensure an adequate sample size.
Descriptive and inferential statistical methods will be used to evaluate differences between groups and identify factors associated with HRQoL. Continuous variables will generally be summarized using medians and interquartile ranges, and categorical variables using frequencies and proportions. Regression analyses will be used to identify possible predictors of better or worse HRQoL.
Participation is voluntary and requires informed consent. Personal data will be handled in accordance with applicable legislation and institutional procedures, with appropriate measures taken to protect participant confidentiality and data security.
- Conditions
- Chiari Malformation Type I
- Keywords
- Chiari Malformation Type I, Health-Related Quality of Life, Registry Data, Survey, cross-sectional
- Medical subject headings
- Arnold-Chiari Malformation
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Chiari Malformation Type 1, operated | Patients identified via the National Patient Register to have 1) diagnosis of Arnold Chiari Malformation (ICD-code Q07.0), 2) received posterior fossa decompression (procedure code ABE50), 3) no record of spina bifida diagnosis (Q05.X), which would indicate Chiari Malformation type 2. The group was limited to the years 2011-2024 to ensure approximately 2/3 of 1000 patients, resulting in 666 eligible participants. Only patients ≥18 years of age at the time the diagnosis was first recorded were included. | |
| Chiari Malformation Type 1, non-operated | Patients identified via the National Patient Register to have 1) diagnosis of Arnold Chiari Malformation (ICD-code Q07.0), 2) the diagnosis recorded at a visit to a neurosurgical unit, 3) no record of posterior fossa decompression (procedure code ABE50) or the similar procedures duraplasty (procedure code AAK10) or another operation on the cranium or dura (procedure code AAK99), 4) no record of spina bifida diagnosis (Q05.X), which would indicate Chiari Malformation type 2. The group was limited to the years 2021-2024 to ensure approximately 1/3 of 1000 patients, resulting in 338 eligible participants. Only patients ≥18 years of age at the time the diagnosis was first recorded were included. |
What is being measured
The primary outcome is the main question the study is designed to answer.
EQ-5D index score
Combined value of the five dimensions of the Euroqol five-dimensional three level (EQ-5D-3L) questionnaire, based on the United Kingdom value set. The index score has a value between 0 and 1, where 1 represents full health.
Measured: Baseline
EQ-5D VAS score
The Euroqol five-dimensonial (EQ-5D) visual analog scale (VAS). The respondents rate their current health between 0 (worst imaginable health) and 100 (best imaginable health).
Measured: Baseline
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted14 Sep 2026
- Study start12 Aug 2026
- Primary completionNov 2026 (estimated)
- Study completionDec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Chiari Malformation Type IStudies of the same condition, open and under way.
- More trials run by Karolinska InstitutetThe sponsor's other registered studies.
- 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
- Observational
- Observational model
- Cohort
- Time perspective
- Cross-sectional
- Enrolment
- 1,004 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Karolinska Institutet
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Adrian Elmi Terander, Karolinska Institutet
- Investigators
- Adrian Elmi-Terander, MD, PhD, Principal investigator, Department of Clinical Neuroscience, Karolinska Institutet
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07818122
- Sponsor's protocol ID
- 2024-03244-01
- Status last verified
- Sep 2026
- First submitted
- 27 Aug 2026
- Last updated
- 14 Sep 2026
- Results posted
- No
- Individual data sharing
- Yes: Metadata describing the dataset will be made publicly available through the Karolinska Institutet (KI) Data Repository.
Study at a glance
From the registry record, last updated by the sponsor on 14 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Health-related Quality of Life in Chiari Malformation Type 1 - A National Cross-Sectional Patient Survey
- ClinicalTrials.gov ID
- NCT07818122
- Acronym / sponsor ID
- 2024-03244-01
- Conditions
- Chiari Malformation Type I
- Keywords
- Chiari Malformation Type I, Health-Related Quality of Life, Registry Data, Survey, cross-sectional
- Study type
- Observational
- Recruitment status
- Enrolling by invitation
- Enrolment
- 1,004 participants (estimated)
- Lead sponsor
- Karolinska InstitutetUniversity, hospital or other
- Study start
- 12 Aug 2026 (actual)
- Primary completion
- Nov 2026 (estimated)
- Study completion
- Dec 2026 (estimated)
- First posted
- 14 Sep 2026 (actual)
- 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 goal of this observational survey study is to investigate factors that may affect the health-related quality of life (HRQoL) in adults with Chiari malformation type 1 (CM1). The main questions it aims to answer are:
How do CM1 patients rate their HRQoL compared to the general population? Are there any factors that lead to better or worse HRQoL in CM1 patients? Is there a difference in HRQoL in operated versus non-operated CM1 patients?
Participants will be identified via the Swedish National Board of Health and Welfare's Patient register. They will be asked to participate in a survey of HRQoL containing standardized questionnaires, and their answers will be analyzed together with data from the Patient register. Their questionnaire answers will also be compared to normative Swedish data.
Detailed description
This is an observational, cross-sectional survey study investigating health-related quality of life (HRQoL) in adults with Chiari malformation type 1 (CM1).
A total of 1,004 adults with CM1 will be invited to participate, including 666 patients who have undergone surgery for CM1 and 338 patients who have not. Participants were identified through the Swedish National Board of Health and Welfare's National Patient Register, which holds data on all inpatient episodes as well as specialized outpatient visits in Sweden.
Operated patients were identified based on diagnosis of Arnold Chiari Malformation (ICD-code Q07.0) and posterior fossa decompression (procedure code ABE50) recorded in the National Patient Register between 2011 and 2024. Non-operated patients were identified based on a diagnosis of CM1 (ICD-10 code Q07.0) recorded during a visit to a neurosurgical outpatient clinic between 2021 and 2024. Patients with a diagnosis of spina bifida (ICD-10 code Q05.X) were excluded from the overall cohort. Non-operated patients with a record of duraplasty (procedure code AAK10) or another operation on the cranium or dura (procedure code AAK99) were excluded.
Participants will be contacted by mail and invited to complete an online survey administered through REDCap, hosted by Karolinska Institutet. The survey includes the Swedish version of the EQ-5D-3L, including the EQ Visual Analogue Scale (EQ-VAS), the Hospital Anxiety and Depression Scale (HADS), and a study-specific questionnaire focusing on clinical characteristics, medication use, sick leave, return to work, and attitudes toward surgical treatment.
Survey data will be linked to relevant information from the National Patient Register and the Swedish Social Insurance Agency. Register data will include information on diagnoses, surgical treatment, comorbidities, and relevant social insurance variables.
The primary outcomes are HRQoL measured using the EQ-5D-3L index score and EQ-VAS score. HRQoL will be compared with normative data collected from a general population in Stockholm, Sweden. HRQoL and associated factors will also be compared between operated and non-operated participants.
A priori power calculations indicated that, assuming a clinically relevant difference of 0.10 in EQ-5D index score, a standard deviation of 0.25, and a two-sided α of 0.05, responses from approximately 22% of the study population would be sufficient to achieve 80% power. Since the expected response rate is 30-50%, approximately 1,000 patients were chosen to ensure an adequate sample size.
Descriptive and inferential statistical methods will be used to evaluate differences between groups and identify factors associated with HRQoL. Continuous variables will generally be summarized using medians and interquartile ranges, and categorical variables using frequencies and proportions. Regression analyses will be used to identify possible predictors of better or worse HRQoL.
Participation is voluntary and requires informed consent. Personal data will be handled in accordance with applicable legislation and institutional procedures, with appropriate measures taken to protect participant confidentiality and data security.
Study design
- Observational model
- Cohort
- Time perspective
- Cross-sectional
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Chiari Malformation Type 1, operated | – | –Patients identified via the National Patient Register to have 1) diagnosis of Arnold Chiari Malformation (ICD-code Q07.0), 2) received posterior fossa decompression (procedure code ABE50), 3) no record of spina bifida diagnosis (Q05.X), which would indicate Chiari Malformation type 2. The group was limited to the years 2011-2024 to ensure approximately 2/3 of 1000 patients, resulting in 666 eligible participants. Only patients ≥18 years of age at the time the diagnosis was first recorded were included. |
| Chiari Malformation Type 1, non-operated | – | –Patients identified via the National Patient Register to have 1) diagnosis of Arnold Chiari Malformation (ICD-code Q07.0), 2) the diagnosis recorded at a visit to a neurosurgical unit, 3) no record of posterior fossa decompression (procedure code ABE50) or the similar procedures duraplasty (procedure code AAK10) or another operation on the cranium or dura (procedure code AAK99), 4) no record of spina bifida diagnosis (Q05.X), which would indicate Chiari Malformation type 2. The group was limited to the years 2021-2024 to ensure approximately 1/3 of 1000 patients, resulting in 338 eligible participants. Only patients ≥18 years of age at the time the diagnosis was first recorded were included. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- The study population consists of adult patients with Chiari malformation type 1 (CM1) identified through the Swedish National Patient Register, which contains nationwide information on inpatient and specialized outpatient care. To ensure diagnostic validity, non-operated patients were included only if they have a documented evaluation at a neurosurgical unit. Operated patients were identified through procedure codes recorded in the register.
Key inclusion criteria (3 listed)
- diagnosis of Arnold Chiari Malformation (ICD-code Q07.0)
- for operated patients: record of posterior fossa decompression (procedure code ABE50)
- for non-operated patients: the diagnosis Q07.0 recorded during an outpatient visit to a neurosurgical unit
Key exclusion criteria (2 listed)
- record of spina bifida diagnosis (Q05.X)
- for non-operated patients: record of the procedures duraplasty (procedure code AAK10) or another operation on the cranium or dura (procedure code AAK99)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
EQ-5D index score
Time frame: Baseline
Combined value of the five dimensions of the Euroqol five-dimensional three level (EQ-5D-3L) questionnaire, based on the United Kingdom value set. The index score has a value between 0 and 1, where 1 represents full health.
EQ-5D VAS score
Time frame: Baseline
The Euroqol five-dimensonial (EQ-5D) visual analog scale (VAS). The respondents rate their current health between 0 (worst imaginable health) and 100 (best imaginable health).
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 14 Sep 2026.
- Individual participant dataSharing planned: Yes. Metadata describing the dataset will be made publicly available through the Karolinska Institutet (KI) Data Repository.
Related trials for Chiari Malformation Type I
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Analysis of Disturbances in Neurofluid Dynamics in Type I Chiari Malformations
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Not yet recruiting
Abnormality of the Central Canal of the Spinal Cord in Syringomyelia in a Patient With a Basal Skull Malformation
Chiari Malformation Type I, Syringomyelia
RecruitingObservational study
Neurosurgical Outcome Network
Aneurysms, Arteriovenous Malformations
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.
Adrian Elmi-Terander, MD, PhD principal investigator
Department of Clinical Neuroscience, Karolinska Institutet
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Chiari Malformation Type I, run by Karolinska Institutet at 1 site in Sweden.
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 3 inclusion and 2 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: enrolling by invitation, as of the sponsor's last update on 14 Sep 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 Sweden. 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?
EQ-5D index score (time frame: Baseline). The study lists 2 primary outcomes in all. 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 14 Sep 2026.