Monitoring visits are a crucial part of clinical trials, allowing trial data in eCRFs to be checked for accuracy and completeness against source data at sites. Monitors may also check the completeness of essential trial documentation within the trial master file. These visits are critical for assuring regulatory compliance according to GCP guidelines, by making sure sites are complying with the study protocol and ensuring data integrity, therefore protecting participants’ rights and safety.

On-site monitoring visits involve a trial monitor – working for or on behalf of the sponsor – visiting a site to review source patient medical records and essential trial documents. On the contrary, remote monitoring is conducted purely online, with a trial monitor granted special permissions to access trial patient source data, primarily electronic medical records (EMRs), or by viewing scanned copies of paper source documents if necessary. When choosing between these types of visits, it is important to weigh up the strengths and weaknesses of each method and how they meet the requirements of a study.

One of the main advantages of on-site monitoring over remote monitoring is that some aspects of the study can be reviewed in person that cannot be reviewed remotely. For example, a monitor can visit site facilities, count pharmacy stock, and look at paper documents in person to identify and rectify potential issues there and then. On-site visits also allow for face-to-face meetings with study team members to discuss study progress or any findings from the visit. Such close monitoring practices may be best suited for early-stage trials, where resolving site-level issues is more time sensitive in order to ensure the safety of participants.

However, on-site visits can be very costly for sponsors, as they require travel expenses for the monitor to get to and from the site, and accommodation if the visit takes place across multiple days. This may also be an inefficient use of time for monitors, who often spend many hours per week travelling to different sites across the country. On-site visits are also time-consuming for sites, as staff must prepare for on-site visits by gathering paper documents, setting up monitoring spaces, and acting as a guide for the monitor around the site throughout the day. Furthermore, the number of monitoring spaces at a site on a particular day is limited and dependent on the site’s facilities, meaning less flexibility and availability when booking these visits.

On the other hand, remote monitoring visits do not face the same cost and time efficiency issues as on-site visits, as monitors can view source documents electronically from their workspace without the need to travel to sites. As more sites shift towards primarily using EMRs to document trial visits, the need to review paper records in person is lessening and therefore remote access to EMRs is a much more straightforward option. In cases where sites still document trial visits on paper, the study team can selectively scan these based on outstanding datapoints to be validated, meaning monitors do not have to spend time sorting through paper documents themselves to find the relevant data. The preparation time for this is much less than for an on-site visit and therefore, paired with fewer restrictions on the number of monitoring spaces per day, remote monitoring arguably makes for a more productive way of validating source data.

Remote monitoring visits, however, are not without their drawbacks. Firstly, they rely solely on electronic systems which are subject to occasional technical issues that can be time consuming to resolve. Furthermore, if sites keep paper Trial Master Files (TMFs), it is not possible for monitors to review essential trial documentation, so remote visits may need to be supplemented with occasional on-site visits to review these. Typically for remote visits, follow-up emails or calls are required afterwards to resolve action items or queries identified during the visit. These may take longer to address than if the issues were discussed and actioned during an on-site meeting, so addressing these remotely may be more appropriate for later phase trials with more established medicinal products and devices, where study requirements are less time sensitive. 

In conclusion, the choice between remote and on-site monitoring depends on trial requirements and priorities, along with sponsor resources. Remote monitoring can save huge costs and is generally less time consuming for both monitors and sites. It is unsurprising that this is therefore becoming a preferred option for sites using EMRs and electronic TMFs for trial documentation. However, for studies which require closer monitoring or are largely paper based, on-site visits may be preferable if the greater cost of this is feasible for sponsors. It is important to weigh up all these factors when choosing a monitoring approach, in order to ensure regulatory compliance and smooth trial practices.

Author: Lydia Ainsworth

Date: 18 April 2024