External Multicenter Validation of the APTTO Model for Prolonged APTT Using Clot Waveform Analysis (NCT07418099) | Clinical Trial Compass
RecruitingNot Applicable
External Multicenter Validation of the APTTO Model for Prolonged APTT Using Clot Waveform Analysis
Spain1,500 participantsStarted 2026-01-13
Plain-language summary
Prolonged activated partial thromboplastin time (APTT) is a frequent laboratory finding that may reflect a broad spectrum of underlying conditions, ranging from benign laboratory abnormalities to clinically relevant hemostatic disorders. Clot waveform analysis (CWA), automatically generated during routine APTT testing by optical coagulation analyzers, provides additional quantitative and qualitative information on clot formation dynamics.
The APTTO model is a previously developed two-step predictive algorithm based on CWA features designed to estimate the probability of a pathological cause of prolonged APTT and to differentiate lupus anticoagulant from intrinsic pathway factor deficiency or von Willebrand disease. Internal validation has demonstrated good discrimination and calibration.
This multicenter observational study aims to perform an external validation of the APTTO model in independent patient cohorts, assessing its discrimination, calibration, and decision-analytic performance without model updating.
Who can participate
Sex
ALL
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AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria
. Patients of any age (pediatric and adult populations) undergoing coagulation testing with:
. Availability of clot waveform analysis (CWA) data obtained during routine APTT testing using:
. Completion of the standard laboratory evaluation for prolonged APTT as part of routine clinical care, when clinically indicated.
. Samples collected and processed in accordance with the standardized preanalytical protocol defined in the study SOP.
. Patients evaluated in either:
Exclusion criteria
. Prolonged prothrombin time (PT) or combined prolongation of PT and APTT.
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Discriminatory performance of the APTTO model
Timeframe: Baseline (at the time of prolonged APTT laboratory assessment)
Trial details
NCT IDNCT07418099
SponsorInstituto de Investigación Sanitaria de la Fundación Jiménez Díaz