Prospective chest CT cohort with opportunistic multidimensional phenotype capture in routine care at a tertiary...

Routine chest CT contains clinically relevant multidomain information beyond the immediate examination indication, but translation into routine care requires more than identifying individual biomarkers. This protocol describes a prospective observational cohort designed to evaluate whether technical assessability, standardised multidomain research phenotyping, routine radiology reporting and documented care can be linked reproducibly within routine clinical chest CT at a tertiary hospital in western China.

This is a single-centre, prospective, consecutive-enrolment observational imaging cohort embedded in routine outpatient and inpatient chest CT practice rather than a dedicated screening programme. The study is organised around a scan-to-phenotype-to-report-to-care framework while retaining a phase 1 feasibility- and implementation-focused primary objective. The initial cohort target is approximately 3000 prospectively consented adults. At the time of this revision, formal recruitment has not commenced and no participant-level study data have been collected or analysed; recruitment will begin after funding and operational preparations are completed and any required ethics notification or amendment has been addressed. The core clinical-reporting layer includes pulmonary nodules, emphysema, interstitial lung abnormalities, coronary artery calcification and pulmonary artery/ascending aorta metrics. The extended measurement layer includes vertebral attenuation, vertebral deformity, thoracic muscle metrics and liver attenuation-based variables when technically assessable. Research phenotyping will be completed independently before routine-report abstraction. Primary phase 1 analyses will assess screening and enrolment flow, baseline data completeness, core phenotype assessability, report-quality abstraction completion and availability of within-system 6-month follow-up data. Secondary analyses will describe phenotype frequencies and distributions, cross-domain co-occurrence, report-quality indicators and early care-pathway documentation using prespecified operational definitions and variable-specific denominators. Descriptive estimates will be reported with 95% confidence intervals where appropriate. Follow-up will occur at 6 months, 12 months and annually thereafter using routine hospital systems. No additional research imaging is planned, and repeat chest CT is not mandated by the protocol.

The study was approved by the Medical Ethics Committee of Dazhou Central Hospital, Dazhou, China (approval no. 2026(084); approved 27 April 2026), and written informed consent will be obtained before cohort enrolment and research data abstraction. Potentially actionable research-identified findings will undergo senior radiologist confirmation and, when confirmed and not already adequately addressed in routine care, will be communicated through the institutional clinical pathway. Planned outputs include a cohort profile or baseline resource paper and subsequent phenotype-specific analyses.

Not applicable. This is an observational cohort protocol rather than a clinical trial.