In one of the latest FDA reports on global participation in clinical trials in the period 2015-16, Poland is the fourth-largest centre for clinical trials worldwide with an estimated recruitment of >5000 trial participants, amounting to almost 4% of the global recruitment (Figure 1).[1] 
In addition, with regards to the EU, Poland ranks a close second behind Germany (4.4%) and occupies the first spot among the CEE countries.

Figure 1. Number and proportion of clinical trial participants ranked by country. Source: USFDA.

The main  factors that affect patient recruitment

In this chapter, we will identify factors that affect patient recruitment and discuss ways to ensure that patients continue participation for the duration of the trial.

So what are some of the general factors that could affect patient recruitment?

  • Perhaps the most important factor when it comes to patient recruitment is the prevalence of the indication under investigation in a clinical trial. When a health condition is fairly uncommon in a region or country, it is tenuous to recruit patients who meet the eligibility criteria. However, most sponsors and CROs do consider disease prevalence while conducting feasibility analysis.
  • When it comes to study sites, the issue of recruitment is also governed by the location (central versus remote), specialty (e.g. oncology centres, heart disease centres, diabetes clinics, etc.), and appropriate facilities at the centre to conduct clinical trials.
  • A well-designed protocol cannot be overestimated as it is one of the fundamental tools for conducting the study. Hence, the study protocol must be of a high quality in order to serve investigator to provide the expected high-quality data.
  • The type and extent of services provided by CROs could also affect patient recruitment. CROs that are knowledgeable on identifying target populations and appropriate centres in their countries of operations provide valuable feedback to sponsors and this indirectly improves patient recruitment. Good relationship with the investigator and site staff, appropriate support, availability and effective response in case of emerging issues in the study may be crucial for the recruitment success.
  • Lastly, we cannot forget one of the most important influencers of good recruitment – the investigator – who interacts with potential study recruits, patiently explains the purpose and design of the study, wins their trust, and is thus successful in recruitment.

Remember importance of the informed consent and clinical staff approach

Besides these general factors, one needs to also consider specific factors that have a bearing on patient recruitment. These can be broadly classified as patient-oriented (informed consent) and clinical staff-oriented:

Informed consent

  • Informed consent– is not only a regulatory and ethical requirement but also one of the drivers of successful recruitment. A patient who is well-informed about the goal of the clinical trial, the procedures and duration of study, the support provided and safety measures in place, etc., not only develops interest in the trial but is also more adherent to the trial protocol. This, in turn, reduces the number of protocol violations and increases the likelihood of patient retention in the study. The key to a well-informed patient is the informed consent form (ICF; including the patient information sheet), guidelines for which have been laid down by the ICH GCP.[2]

The crucial role of the investigator in providing informed consent process is often overlooked. In her presentation at one of the workshops from the Polish Association for Good Clinical Practice, Dr. Ewa Czernecka, an experienced investigator, explained the importance of an effective informed consent in patient recruitment and retention. Dr. Czernecka strongly emphasised the need for an amenable atmosphere at the study site, clear information transfer to the patients in a personalised manner, a readiness to answer patient questions, a consideration and respect for the patient, and building patient–investigator partnership in order to achieve successful patient recruitment. By following these recommendations, we increase the chance of maintaining good relationships with the patient throughout the study.

Ensuring the patients’ retention

  • While discussing patient recruitment, it is also pertinent to consider the issue of ensuring the patients’ continued enrolment till their individual endpoints are attained. Here again, as is at the time of enrolment, the patient-investigator/trial staff interaction plays a large role. The trial staff should ensure that the patient is kept informed at all stages, especially with respect to new safety information or protocol changes. They also need to bear in mind situations such as a disability which precludes the patient from making a scheduled visit and arrange for alternatives.

According to a survey published in 2016, the key competitive advantage held by Poland over the EU-15 countries was, inter alia, efficient patient recruitment.[3] This is also one of ACT’s achievements – we are proud of a remarkably high patient recruitment rate at Polish sites in the international projects, owing to our experience in identifying appropriate sites and investigators, conducting staff training, drafting effective ICFs, and efficient trial monitoring. In addition, ACT also offers certain specialised services for benefit of the patients such as nursing services at the patient’s home for some assessments, sample collection, etc. Besides this, we also handle operational details such as patient reimbursement and cost settlement on behalf of the sponsors. Taken together, these services have been instrumental in successful patient recruitment.

Upcoming changes in the regulatory guidelines

In the next topic we will discuss the upcoming changes in the regulatory guidelines on new interventions, including medical devices, in the European Union, and evaluate the impact these having on the clinical trial process.

[1] FDA  2015 – 2016 Global participation in clinical trials report (2017). Available from:

[2] ICH GCP. Informed consent of trial subjects. Available at:

[3] PricewaterhouseCoopers Group. Clinical trials in Poland. December 2015. Available at: