About PEN

As busy practitioners, it can be challenging to stay abreast of the latest science in food and nutrition - especially in today’s ever-changing environment. Diet manuals and textbooks served practitioners well in the past, but are often limited in their scope and can be out-of-date even before they are published.

To address the need of health professionals as effective knowledge managers in today’s dynamic environment, Dietitians of Canada developed PEN: Practice-based Evidence in Nutrition® – The Global Resource for Nutrition Practice.

A Dynamic, Evidence-based Service
Practice-based Evidence in Nutrition (PEN) is a dynamic knowledge translation tool. Canadian Institutes of Health Research defines "knowledge translation" as the exchange, synthesis and ethically-sound application of knowledge - within a complex system of interactions among researchers and users - to accelerate the capture of the benefits of research for Canadians through improved health, more effective services and products, and a strengthened health care system" (1).

The PEN System provides nutrition practitioners with ready access to timely, current and authoritative guidance on food and nutrition. It offers evidence-based answers to the questions encountered in every day practice.

The PEN System’s powerful search tools and Knowledge Pathway format make it easy to use – whether you’re pressed for time and looking for a quick answer, or you want to review the evidence in more depth.

A Collaboration of Global Dietetic Organizations
The PEN System was developed by Dietitians of Canada, with input from thought leaders in dietetic practice, knowledge translation and technology.

It is managed by a collaborative partnership comprised of the British Dietetic Association, Dietitians Australia and Dietitians of Canada.

See the PEN Contributors page for more information on the PEN® Team.

The PEN System Supports Decision-making for:

  • Clinicians through best practice point-of-care guidance to improve inpatient, outpatient and private practice client health outcomes and reduce health care costs
  • Public Health/Community Practitioners through complete population health and lifecycle practice guidance based on best evidence
  • University Educators as a teaching tool in critical appraisal and evidence-based decision-making
  • Food Service Administrators through up-to-date best evidence in issues, such as food safety and nutrient analysis software
  • Policy-makers as an evidence-based reference to guide policy development
  • Food Manufacturers for a synthesis of latest research on consumers' understanding of food labels and health claims.

Knowledge Pathways: The ‘Backbone’ of the PEN System
The PEN System is made up of topics called Knowledge Pathways. Standard Knowledge Pathway tools include Practice Questions, Backgrounds, Evidence Summaries and Practice Guidance Toolkits, as well as client and professional Tools and Resources, including Client Handouts.

For each Knowledge Pathway, practitioners and experts determine relevant practice-based questions. Evidence Analysts are involved in identifying literature (from filtered and original sources) and critically appraising, grading and synthesizing the findings into key practice points or recommendations to address the Practice Questions. As new evidence emerges, Knowledge Pathways are updated to ensure that practice guidance is current. New Knowledge Pathways are created based on feedback from PEN System subscribers, partners and the PEN Team. The best evidence-based client and professional tools and resources are included in PEN website to support practice.

The PEN® System addresses the broad spectrum of practice in dietetics, food and nutrition including:

  • institutional health care
  • primary health care
  • public/community health
  • consulting/private practice
  • food service management
  • professional education
  • food and the pharmaceutical industries
  • government. 

How is the PEN® System Funded?
The PEN System is funded by professional associations, subscription and licensing revenues, government grants and health authority contributions. View the Key Contributors to the PEN System.

 The PEN® System is Not Funded by any Corporate Sponsorship and Commercial Advertising is not permitted
The PEN System does not accept corporate sponsorship for the production or updating of practice guidance provided in the Knowledge Pathway content nor does the PEN System host or receive funding from advertising or from the display of commercial content. Revenue to support keeping the database current and growing comes from the partner dietetic associations, subscription and licensing fees, and some government grants.

Finding the Evidence: The PEN Process
Validated and refined filtered information form the basis for the evidence synthesis for the PEN System and include:

  • synopses
  • well-conducted systematic reviews (such as Cochrane Reviews)
  • reputable practice guidelines. 

If filtered sources fail to address practice questions, PubMed and other specialty databases are used to identify relevant and scientifically valid articles for analysis and synthesis.

Authors document their search strategies on the Search Strategy Worksheet.

Once drafted, the new or revised PEN content is reviewed by experts in practice, academics and PEN Team members. The final copy is edited and integrated into the PEN website.

Evidence Grading
The PEN® System uses two approaches to grading the evidence. In 2015 the PEN partners made the decision to adopt the GRADE approach to developing practice recommendations. This approach is best suited to Practice Questions that compare interventions. Going forward, GRADE is being used for new and updated Practice Questions that meet this criteria.

The strength of the recommendation and the quality of the evidence used to make the recommendation are both evaluated in the GRADE approach. Recommendations are evaluated to be either Strong or Weak and the quality of evidence is rated as high, moderate, low or very low.

PEN System Evidence-based Process 
Other types of Practice Questions, such as those pertaining to diagnosis or prognosis, will continue to be addressed using the PEN System evidence-based process. In these circumstances, key practice points are assigned an evidence grade by the Knowledge Pathway author using the PEN® grading protocol:

  • Level A - the conclusion is supported by good evidence 
  • Level B- the conclusion is supported by fair evidence
  • Level C - the conclusion is supported by limited evidence or expert opinion
  • Level D - evidence is from limited studies that are either such poor quality or too conflicting that no conclusions can be made. No evidence from either authoritative sources or research involving humans was found.

See the PEN Authors and Reviewers Guide for a full description of the PEN® approach to retrieval, synthesis and grading of evidence, and for more information on the levels of evidence.  

See Additional Information:
PEN System Terminology and Features


Updated/Reviewed April 19, 2021