How to define a realistic study timeline before starting project activities?
Preparing a realistic timeline is one of the key factors determining the success of any clinical trial, medical experiment, or observational study, where resources are limited and every delay leads to increased costs and operational risk. A good timeline should not be a set of wishful deadlines, but a project roadmap based on concrete operational data, the actual volume of documentation required, the CRO’s experience, the average duration of regulatory and administrative processes, and a thorough feasibility assessment. It is particularly important to plan three main phases: study start-up, maintenance, and close-out. The most common mistake made by Sponsors is setting overly ambitious deadlines “off the top of their head,” without consulting the CRO and assuming that “it might work.”
The start-up phase in clinical trials is far more complex than in observational projects or medical experiments, primarily due to the requirement to obtain approval from the Office for Registration of Medicinal Products (URPL). In practice, realistic preparation for a clinical trial takes 4–10 months, while in other project types it ranges from 2–6 months. This period includes preparing documentation and systems (1–3 months), obtaining ethics committee and URPL approvals (1–3 months), and site negotiations and activation (1–4 months depending on the number of sites). Each stage has its own dynamics — the more complex the protocol, the longer the process.
The maintenance phase is the most variable component of the timeline. Its duration depends mainly on the real — not declared — recruitment rate. Based on feasibility data, experience from similar projects, and an analysis of competing studies, a CRO can estimate a realistic enrollment pace. In practice, site declarations tend to be overly optimistic. To avoid surprises, it is advisable to work with three scenarios — optimistic, realistic, and conservative.
The study close-out phase is often overlooked or excessively shortened at the planning stage, even though it significantly affects the final deadlines. Final SDV, query resolution, site closures, vendor wrap-up, database cleaning, statistical analysis, and preparation of the final report require at least 3–5 months — and with more complex protocols even 6 months or more.
A realistic timeline emerges only when all elements are combined with a risk analysis, evaluation of site resources, and the CRO team’s practical experience. A plan prepared in this way minimizes delays, enables precise budget management, and provides full transparency for the Sponsor.
If you would like to validate your preliminary timeline or ensure it reflects all steps required for efficient project execution, a consultation with an experienced CRO is the best first step.
