• ICN

Progress Towards Priorities for the International Collaborative Network for N-of-1 Trials and SCDs

In early 2019, an online survey was sent to members and promoted to others on social media to elicit views about key priorities and the strategic direction of the International Collaborative Network for N-of-1 Clinical Trials and Single-Case Designs (ICN).

The 75 respondents reported the following activities as top priorities for 2019:

  1. Collecting and sharing a comprehensive set of resources, guidelines and tips;

  2. Developing a communications strategy and strengthening online presence;

  3. Establishing consumer engagement and partnership;

  4. Streamlining ethical approval processes;

  5. Exploring perceived myths about single-case designs (SCDs);

  6. Writing position papers to outline key priorities.

The ICN committee developed a strategic plan for achieving these priorities and here we summarise progress to date.

Collecting and sharing a comprehensive set of resources, guidelines and tips

We added a range of resources such as e-courses, guidelines, books, websites, analysis resources, reviews and special journal issues related to the design, conduct and analysis of SCDs to the ICN website. We added an “advice needed” button on the ICN website for people to submit queries related to any aspect of the design, conduct and analysis of SCDs.

Strengthening online and physical presence

In 2019 we:

  • Developed a communications strategy

  • Were active on Twitter and LinkedIn

  • Shared SCD news and promoted members’ publications, resources and events through the website and monthly newsletters.

  • Began a study identifying myths around the value of SCDs as a valid research methodology for interventional and observational studies.

  • Delivered seminars and workshops to showcase the value, benefits and applications of SCDs and provide tips for designing, conducting, and analysing SCDs.

  • Delivered a workshop in Ireland for Trial Methodology Research Network

  • Presented at the Australian Clinical Trials Alliance annual conference in Sydney about ICN.

  • Delivered teaching about SCD methods to bachelor, Master and PhD students

  • ICN members organised a SCD symposium, “Small is beautiful”, in Stockholm, which attracted over 250 participants.

Consumer engagement and partnership

Two consumer representatives have joined the ICN committee and provided crucial input into the ICN’s consumer and partnership engagement strategy. The ICN also developed links with various consumer organisations in Australia and overseas.

Streamlining ethics approval processes

ICN members are working on simplifying ethics applications for N-of-1 trials and SCEDs to facilitate future SCD clinical research, especially when only one participant is involved.

Exploring perceived myths about SCDs

ICN members are currently conducting a systematic review and developing surveys to identify and address barriers to the design, conduct, analysis, interpretation and adoption of SCDs. A rigorous evaluation of common statistical/design concerns in pooled N-of-1 trials compared these trials to parallel and cross-over RCTs using simulations. It showed appropriately designed pooled N-of-1 trials offer substantial advantages over RCTs.

State of the art/position papers

Organisers of the Small is beautiful” SCED symposium wrote a paper summarising the conference presentations and pre-conference expert meeting. A manuscript about the purpose and priorities for the ICN has been submitted to BMJ Evidence-Based Medicine.

Other activities

ICN co-chairs JN and SM guest-edited a special issue on “N-of-1 trials in Healthcare”, published in the journal Healthcare, and with others are co-editors of special topic Creating evidence from real world patient digital datapublished in Frontiers. These contain 13 and 4 published articles respectively, with 13 more expected for the Frontiers special topic.

The ICN is also supporting development of Trial-Ready Registry Framework, an open-source digital infrastructure to support N-of-1 and adaptive clinical trials and ‘trial-ready’ observational studies.

Where to next?

Our activities have been impacted by the coronavirus pandemic but we will continue to work towards the goals identified by ICN members for 2020 as best we can. These include:

  • Facilitating partnerships between people working on N-of-1/SCD methods across the world,

  • Delivering online workshops,

  • Establishing SCD registries and

  • Obtaining funding to support the ICN’s activities.

We will report at the end of the year on the progress we have made towards achieving our priorities for 2020.

About the authors


Associate Professor Jane Nikles is a registered Medical Practitioner who conducts research at The University of Queensland. Jane has 20 years’ experience in conducting N-of-1 trials and has a particular interest in improving the science of N-of-1 trials and exploring the applications of these trials to maximise patient health outcomes. Jane is co-chair of the ICN


Dr Suzanne McDonald is a chartered health psychologist interested in the development and application of N-of-1 trials, SCEDs and Single-Case Observational Designs (SCODs) in medicine and psychology. Suzanne has applied these methods to study a range of health-related behaviours and chronic symptoms. Suzanne is co-chair of the ICN.