The TRAjectory of knee heaLth in runners (TRAIL) study is a prospective cohort study investigating the long-term knee health trajectories of runners with and without a heightened osteoarthritis risk. This study aims to describe the recruitment results and baseline characteristics of the TRAIL cohort.

Runners aged 18–50 years and running ≥3 times and ≥10 km per week on average in the past 6 months were eligible. Participants were recruited via running podcasts, running clubs and social media between July 2020 and August 2023. Data were collected at study enrolment and at a face-to-face baseline testing session, which occurred a median of 33 weeks (IQR 18 to 86 weeks) after enrolment. Follow-up data collection is ongoing.

Out of 462 runners who completed an online registration form, 268 runners enrolled, of which 135 had a history of knee surgery (46% females) and 133 were non-surgical controls (50% females). 60% of the surgery group had undergone anterior cruciate ligament reconstruction, 33% meniscus and/or cartilage surgery, and 7% other knee surgery. 54 participants previously enrolled were unable to continue in the study before attending baseline data collection. Of the 214 runners who remained in the study and attended baseline data collection, 108 had a history of knee surgery (49% females) and 106 did not have a history of knee surgery (51% females).

Participants will be followed for 10 years through ongoing patient-reported outcomes and continuous monitoring of training loads using wearable devices. At baseline, 4- and 10-year follow-up, knee MRI and knee-health patient-reported outcomes will be collected to evaluate structural and symptomatic knee osteoarthritis progression. Data will inform guidelines for safe running practices and rehabilitation post-knee surgery.

Recent studies have demonstrated a beneficial role of steroids in severe community-acquired pneumonia, severe COVID-19 infection and acute respiratory distress syndrome (ARDS) of diverse aetiology. This multicentre randomised controlled trial in severe scrub typhus pneumonitis and ARDS will compare the effects of 6 mg of dexamethasone once per day with placebo, in addition to standard treatment, on ventilator-free days (VFD), mortality and ventilatory requirement.

The study, involving six sites, will recruit 440 patients with severe scrub typhus pneumonitis or ARDS to concealed, block-randomised, site-specific assignment of dexamethasone or placebo for 4–7 days. The primary outcome will be VFD, defined as days alive and free of ventilation at 28 days. Secondary outcomes will include 28-day mortality, need and duration of ventilation, and treatment failure, defined as death, or escalation of respiratory support from simple devices (nasal cannula, mask) to non-invasive or invasive ventilation, or the use of open-labelled steroids for worsening shock. The study will also ascertain if antinuclear antibody (ANA) expression during the acute phase of illness will predict steroid responsiveness. Subgroup analyses will be conducted a priori on ANA expression and the need for ventilation. All analyses will be conducted on an intention-to-treat basis. The trial, which commenced in April 2025, would clarify the role of corticosteroids in scrub typhus pneumonitis.

The Institutional Review Board and Ethics Committee of the lead site, Christian Medical College, Vellore, India, has approved the study (IRB Min No 15920 (INTERVE) dated 22 November 2023). The remaining five sites have obtained approval from their respective ethics committees. Study results will be published in an international peer-reviewed journal.

CTRI/2024/12/077709. Registered 5 December 2024.