Milestones, Dependencies and the Critical Path

Part of Clinical Project Management (PM) Training: Building a Timeline That Holds.

About 2 minutes. Free, in your language, no account needed.

A timeline is a set of claims about dependency

First patient in is not a date you choose. It is the consequence of regulatory approval, ethics approval, site contracts, drug supply at the site, and site staff trained. Move any one of those and the date moves with it.

The critical path is the chain where a day lost is a day lost to the whole trial. Everything else has slack. Knowing which is which is most of the job.

The dependencies people forget

Drug supply is a long pole. Manufacture, release testing, labeling in the right language, import permits. It frequently takes longer than ethics approval and is planned as though it takes less.

Contracts are a long pole. A site that agreed enthusiastically in feasibility can sit in legal review for months over indemnity or publication rights.

Training is a dependency, not an afterthought. Staff cannot perform trial duties before they are trained on the protocol, and the training has to be documented.

Buffer belongs where the uncertainty is

Spreading contingency evenly across a plan hides it. Put it against the activities that genuinely vary: regulatory review in a new country, first-site activation, the first manufacturing batch.

An activity you have done fifty times needs less buffer than one you have never done in that country.

The plan is a document that changes

A timeline that has not changed in six months is not stable. It is not being maintained.

Re-baselining is a normal act, but it must be a decision with a reason attached, not a quiet edit. The sponsor needs to know the date moved and why. A date that drifts without announcement destroys more credibility than a date that slips openly.