The principal investigator leads a system

The principal investigator remains accountable, while sub-investigators, coordinators and supporting functions need documented responsibilities and adequate resources. Continuity depends on repeatable processes rather than one person’s memory.

Protocol-specific training, delegation, communication paths and escalation rules should be established before recruitment.

Evidence-based feasibility

A credible feasibility response defines the source population, period, inclusion filters, expected losses and competing studies. It should distinguish routinely treated patients from referrals and broad digital enquiries.

Published recruitment ratios cannot be copied as local promises: different studies use different denominators. A forecast should be recalculated for every protocol and updated against screening-log evidence.

Recruitment and participant journey

Patient access may combine routine clinical flow, physician referrals, patient organisations and carefully governed digital navigation. Information materials must avoid therapeutic promises and preserve voluntary choice.

The screening log is an operational learning tool: it reveals where assumptions fail, why candidates are excluded and whether the forecast needs correction.

Quality by design and communication

ICH E6(R3) emphasises proportionate, risk-based quality. Sites should identify critical-to-quality factors, assign owners and make deviations, safety information, data status and blockers visible through agreed communication.

Digital tools can support organisation and preliminary structuring, but clinical decisions and eligibility require qualified human review in the sponsor-approved context of use.

Quick answers

Frequently asked questions

What makes a feasibility response credible?

A defined population, denominator, time window, documented assumptions, competing-trial context and a plan to update estimates with screening data.

Can AI determine eligibility?

Not autonomously. Tools may support search and structuring, but qualified staff must verify source data and protocol criteria under appropriate governance.

Evidence base

Primary and authoritative sources

Use the linked source documents for professional or current interpretation.