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KPIs: how to measure success in clinical trials

Key Performance Metrics or Indicators (KPIs) are the bread and butter of every successful business; hence, why they are one of the essential components of clinical research. KPIs help us understand the clinical recruitment process better - from the first contact with potential candidates to the final visit. Essential to initial planning and crucial to the operation of phase 1 clinical trials, understanding your KPIs, your strengths and your weaknesses, ultimately makes establishing benchmarks and allocating precious resources that bit easier. If that’s not enough, KPIs - being at the heart of your business plan - are they key to strengthening your relationship with clinical trial sponsors, which could give you a competitive advantage.

Today, we take a look at some of the key KPIs research sites should be tracking, and consider how they can improve your current clinical protocol and patient recruitment strategy. Check out our breakdown below.

From "open for enrollment" to "enrollment quota met"

This KPI is all about keeping an eye on the clock, from the start of recruitment until the moment you hit your clinical trial enrollment quota. The shorter this KPI is, the better for your organisation AND the happier your sponsor will be. This seems like a no-brainer, but it is easier than it seems to get lost in your work and lose track of time. As you may be aware, according to a Pharmafile study, around 50% of clinical trials are delayed due to patient recruitment issues. Longer cycles or delays implementing initial patient engagement metrics can indicate that you need to rethink your clinical recruitment procedure.

If your site’s performance for this KPI is good, i.e. your enrollment quota is met on time or - even better - earlier, then you can leverage this in further negotiations with the sponsor. From our own experience, research sites with a shorter time frame from “open to enrollment” until “enrollment quota met” are more likely to get selected first for future trials with clinical trial sponsors.

Cost per enrolled subject

Research sites with a tight budget will agree that the “cost per enrolled subject” should always be a key KPI. Costs are almost always linked with the efficiency of the recruitment method. So, it’s important to remember that a recruitment channel who looks at first sight more expensive can turn out to be more efficient and therefore more cost-effective than a “cheaper” option in the long-run.

Staying in budget and choosing the most cost-efficient recruitment method is, of course, important in order to stay competitive and profitable. Consider our following example of CRO X and CRO Y carefully.

CRO X employs outreach via a local newspaper ad for $250 per week. Per month, this is $1,000. Typically response rates from newspaper ads are not high, and CRO X gets on average 30 potential subjects per month. This is more than $30 per referral, and these potential subjects are not pre-qualified.
Unfortunately, 70% of the people that responded to CRO X’s ad are not eligible for the trial, which reduces the number of patients to 9 and ups the cost to more than $100 per subject. The trial is now delayed. The sponsor is not satisfied, meaning CRO X will not be the first choice for a next trial. This, in turn, brings CRO X back to square one, back to evaluating their basic KPI.
CRO Y, on the other hand, decides to engage with patient recruitment companies, who charge a standard performance-based fee per referral. This looks, at first, more costly than the newspaper ad, but it pays off. Trial recruitment is a lot faster and more efficient. In fact, the CRO meets the clinical trial enrollment quota before the official deadline. What’s more, through a pre-qualification process of potential subjects, the error rate in recruitment is significantly lower. The sponsor is very satisfied and will re-engage CRO Y without hesitation.

As you can see from this example, cost is strongly tied to trial efficiency and the overall time-frame of recruitment. Consider your initial investments carefully as supplying a solid amount of capital into your clinical study will build the strong foundations to support the remainder of your trial operations.

From IRB submit to IRB approval

It’s essential that research sites track the days between submitting their trial protocol to the Institutional Review Board (IRB) and when it is approved. Sometimes, IRB approval can be painfully slow and seems to delay the whole endeavour of conducting a trial. When a site experiences these delays, it is normally a sign that their submission lacks information the IRB requires. The issues vary from application to application, so it is essential that your trial recruitment and clinical protocol is carefully planned as part of your initial feasibility analysis.


Talk to your IRB about the delays directly and make sure to establish a person-to-person point of contact in order to resolve any issues quickly. As you know, IRB approval is usually one of the first milestones in the life cycle of a clinical trial. Use your good track records to your advantage and promote your site accordingly.

Trial retention statistics

Retention, broadly speaking, refers to how many patients clinical studies retain over the course of a single trial. This is a problem almost every research site faces. With an average 30% of participants dropping out over the course of a clinical study, it is no wonder that 85% of clinical trials fail to retain enough patients to operate! While some drop-outs are unfortunately uncontrollable, others are highly preventable.

Retention is all about knowing your audience and being open to fulfilling even the smallest of their needs. Go the extra mile, do the research and work out a general profile for your potential patients. Look to national consensuses and wider social surveys for general trends, with the following questions in mind:

  • What are their priorities in employment, family life, leisure etc.?

  • What forms of communication do they use regularly?

  • What are the lifestyle choices that inform their opinions?

After answering these questions, you should find that your answers make up the basis for your patient-care strategy. However, given the current climate, it may be wise for research operators to look beyond these answers and invest in more secure and reliable methods of retention - sparing them vital time to plan and implement patient-centric care metrics throughout their study. This is, of course, where patient recruitment companies come in.

Not that we are biased, but if we were to recommend any one company for the job it would have to be Citruslabs. Linked to our #1 health app in 17 countries, Mindmate, our patient recruitment dashboard directly connects researchers to over 3 million registered patients. Now, we would say that other models are available - but this would be a lie. In fact, our easy-to-use dashboard is the first-of-its-kind for the market; offering researchers a unique insight into patients’ wants and needs via industry-leading technology. The future of patient recruitment starts here.

Still a little unsure? Check out what our customers have to say about us here.

  • Interested in finding out more? Get in touch with one of our team here, and check out archives for all our top tips and tricks on running a successful clinical trial in today's constantly changing industry.

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