Time burden calculation: the aggregate workload nobody wants to compute
This is the section of the feasibility assessment that separates sites that plan from sites that hope. The time burden calculation takes everything you have estimated -- coordinator hours, investigator time, nursing support, pharmacy touches, equipment scheduling -- and projects it across the entire study timeline. Not just "how much work is one visit." How much work is the entire study, from the first screening visit to the last close-out form, accumulated across all enrolled participants simultaneously.
And I will be direct: most sites skip this calculation. They assess resources per participant per visit, nod that the numbers seem manageable, and move on. What they fail to do is project forward to the point of peak enrollment, when the workload is not one participant's screening visit but 12 participants in various stages of the protocol, each with different visit schedules, some needing unscheduled safety visits, and the screening of new participants continuing in parallel.
The enrollment accumulation curve. Start with your enrollment projection from Lesson 1 of this module. If you expect to enroll two participants per month over a six-month enrollment window, your active participant count builds progressively. In Month 1, you have two active participants. In Month 3, you have six. In Month 6, you have 12 -- and all 12 are simultaneously active, each with their own visit schedule. For a 52-week treatment period, those 12 participants will remain active and requiring visits for months after enrollment closes.
The workload peaks not at the start of the study but months into it, when maximum enrollment has been reached and all participants are in the treatment phase simultaneously. This is the point at which your resources are most strained, and this is the point your feasibility assessment must evaluate.
Factoring in screening failures. Here is a detail that catches sites by surprise. Screening failures consume resources. A participant who consents, undergoes the screening visit, fails a laboratory criterion, and is discontinued has still consumed coordinator time, investigator time, exam room time, and laboratory resources. That work is not recovered. If your expected screen failure rate is 30%, and you need to enroll 12 participants, you should plan to screen approximately 17. Those five additional screening visits are real workload that must be accounted for.
Visit windows and scheduling flexibility. Most protocols define visit windows -- a plus-or-minus range around the target visit date. A bi-weekly visit with a plus-or-minus three-day window means each visit must occur within a seven-day span. Tight windows reduce scheduling flexibility and increase the likelihood that visits will cluster. If four participants are all due for their bi-weekly visit within the same week, the coordinator must accommodate four visits in that window, regardless of what else is scheduled. Loose windows (plus-or-minus seven days or more) provide more scheduling flexibility and reduce peak clustering.
When calculating the time burden, consider the window constraints. Tighter windows mean less ability to spread visits evenly across the week. More clustering means higher peak daily and weekly workloads.
Unscheduled visits. Every protocol includes provisions for unscheduled visits -- typically for adverse event assessment, dose-modification evaluations, or early termination procedures. Unscheduled visits are, by definition, unpredictable. But they are not zero. A reasonable planning assumption, based on my experience across therapeutic areas, is that unscheduled visits add 10% to 20% to the total scheduled visit volume over the life of the study. For a study with 15 scheduled visits per participant and 12 enrolled participants, that is 180 scheduled visits plus 18 to 36 unscheduled visits. The unscheduled visits tend to concentrate during periods of dose escalation or when participants are experiencing new symptoms -- precisely when the coordinator's workload is already elevated.
Close-out activities. The study does not end when the last participant completes the last visit. Close-out activities include final data entry and query resolution, source document verification preparation, investigational product reconciliation and return, regulatory binder completion, essential document filing, archiving, and the close-out monitoring visit. Close-out can consume four to eight weeks of intermittent but substantial coordinator time, depending on study complexity and the volume of outstanding queries. If you are already planning to start a new study as the current one winds down, the close-out workload from the ending study overlaps with the start-up workload for the new one.