ASAS CLassification of Axial SpondyloarthritiS Inception Cohort in the Netherlands

ASAS CLassification of Axial SpondyloarthritiS Inception Cohort in the Netherlands - ASAS CLASSIC study - the Netherlands

Status

Active, not recruiting

Phases

Unknown

Study type

Observational

Source

NL-OMON

Registry ID

NL-OMON48283

Enrollment

Registered

2019-05-15

Start date

2020-01-11

Completion date

Unknown

Last updated

2025-09-15

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

ankylosing spondylitis axial spondyloarthritis

Interventions

None listed

Eligibility

Age

18 Years to 64 Years

Inclusion criteria

Inclusion criteria: Consecutive patients with current undiagnosed low back and/or buttock pain with onset =3 months referred to the rheumatology department for diagnosis in the Netherlands.

Exclusion criteria

Exclusion criteria: • Patients with no back and/or buttock pain during last week • Patients with back and/or buttock pain that lasted less than 3 months • Patients with an onset of back and/or buttock pain after 45 years of age • Patients with pain localized to the groin instead of back pain • Patients with a prior rheumatologist confirmed diagnosis of SpA

Design outcomes

Primary

Measure	Time frame
Primary Endpoint ASAS classification criteria that attain specificity of >=90% and sensitivity of >=75%. If the primary endpoint is met, the protocol will stop and no further analyses that aim to modify the criteria will be made.	—

Secondary

Measure	Time frame
Secondary Endpoints (For assessing the impact of educational intervention) 1. Agreement for detection of MRI lesions on a dichotomous basis (present/absent) between central and local investigators. 2. Agreement for detection of ASAS positive MRI between central and local investigators. 3. Frequency of diagnostic re-categorization by local investigator BEFORE and AFTER central image review and education. 4. Confidence of diagnostic ascertainment by the local investigator after assessment of all obtained information before the central image review and education over time. 5. Agreement between final diagnosis of the local rheumatologists, which is made after being informed about and after having discussed the imaging findings by the central readers, with the diagnosis made by the central clinical committee. Tertiary Endpoint Predictive validity of the ASAS classification criteria over a five-year period, both for the pooled axSpA classification criteria for axSpA as for the imaging and clinical arm separately.	—

Measure

Time frame

Secondary Endpoints (For assessing the impact of educational intervention) 1. Agreement for detection of MRI lesions on a dichotomous basis (present/absent) between central and local investigators. 2. Agreement for detection of ASAS positive MRI between central and local investigators. 3. Frequency of diagnostic re-categorization by local investigator BEFORE and AFTER central image review and education. 4. Confidence of diagnostic ascertainment by the local investigator after assessment of all obtained information before the central image review and education over time. 5. Agreement between final diagnosis of the local rheumatologists, which is made after being informed about and after having discussed the imaging findings by the central readers, with the diagnosis made by the central clinical committee. Tertiary Endpoint Predictive validity of the ASAS classification criteria over a five-year period, both for the pooled axSpA classification criteria for axSpA as for the imaging and clinical arm separately.

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Countries

Netherlands

Outcome results