In a previous post, I described a model I built for 100% QC of documents as part of an eTMF process. We took a look at the impact of the rejection rate for documents jumping from 10% to 15%. It was not good! So, what happens when an audit is announced and suddenly the number of documents submitted doubles? In the graph below, weeks 5 and 6 had double the number of documents. Look what it does to the inventory and cycle time:
The cycle time has shot up to around 21 days after 20 weeks. The additional documents have simply added to the backlog and that increases the cycle time because we are using First In, First Out.
So what do we learn overall from the model? In a system like this, with 100% QC, it is very easy to turn a potential bottleneck into an actual bottleneck. And when that happens, the inventory and cycle time will quickly shoot upwards unless additional resource is added (e.g. overtime). But, you might ask, do we really care about cycle time? We definitely should: if the study team can’t access documents until they have gone through the QC, those documents are now not available for 21 days on average. That’s not going to encourage every day use of the TMF to review documents (as the regulators expect). And might members of the study team send in duplicates because they can’t see the documents that are awaiting processing? Adding further documents and impacting inventory and cycle time still further. And this is not a worst case scenario as I’m only modelling one TMF here – typically a Central Files group will be managing many TMFs and may be prioritizing one over another (i.e. not First In, First Out). This spreads out the distribution of cycle times and will lead to many more documents that are severely delayed through processing.
“But we need 100% QC of documents because the TMF is important!” I hear you shout. But do you really? As the great W Edwards Deming said, “Inspection is too late. The quality, good or bad, is already in the product.” Let’s get quality built in in the first place. You should start by looking at that 15% rejection rate. What on earth is going on to get a rejection rate like that? What are those rejections? Are those carrying out the QC doing so consistently? Do those uploading documents know the criteria? Is there anyone uploading documents who gets it right every time? If so, what is it that they do differently to others?
What if you could get the rejection rate down to less than 1%? At what point would you be comfortable taking a risk-based approach – that assumes those uploading documents do it right the first time? And carrying out a random QC to look for systemic issues that could then be tackled? How much more efficient this would be. See the diagram in this post. And you’d remove that self-imposed bottleneck. You’d get documents in much quicker, costing less and with improved quality. ICH E6 (R2) is asking us to consider quality as not being 100% but concerning ourselves with errors that matter. Are we brave enough as an industry to apply this to the TMF?
Text: © 2019 DMPI Ltd. All rights reserved.
Picture: CC BY 2.0 Remko Van Dokkum