To develop the NCCN Evidence Blocks™, NCCN Panel members score each measure using a standardized scale from "1" to "5" with "1" being the least favorable and "5" the most favorable. For efficacy and safety, panel members use both their knowledge of the published data—often developed in highly selected patients—and their clinical experience with the treatments in the real-world patient population. Quality and consistency of the data are rated using the panel members’ knowledge of the data supporting the treatment. Affordability is rated using the panel members’ knowledge of the overall cost of the regimen.

Resulting data are analyzed and final scores based on all responding panel members, rounding to the closest whole number. These scores are then used to build the 5 x 5 table that constitutes the NCCN Evidence Block™ for the intervention. Each column in the Evidence Block corresponds to an outcome characteristic. From left to right the outcome characteristics are efficacy (E), safety (S), quality and quantity of evidence (Q), consistency of evidence (C) and affordability (A). The rows of the block are shaded in from bottom to top representing the corresponding score for each measure.

The use of a graphical representation of the measures through NCCN Evidence Blocks™ allows for the efficient scanning and interpretation of multiple therapy options in a very efficient manner. When the NCCN Evidence Blocks™ are placed on the NCCN Guidelines algorithm, a user can quickly scan a group of potentially appropriate interventions and make treatment recommendations based on what is most important to the patient. Some patients will want an emerging therapy even with limited data; others will be most concerned about the expected side effects of the treatment indicated in the safety column. Still others may be very sensitive to cost. By considering the attributes of the range of possible therapies, the health care provider and the patient can discuss the benefits and drawbacks of each option and come to a decision most acceptable to the individual.

Panel members used the following criteria to score the measures.

[E] The Efficacy measure is the extent to which an intervention is helpful in prolonging life, arresting disease progression, or reducing symptoms of a medical condition. The scale used to measure efficacy is:

• 5 (Highly effective): Cure likely and often provides long-term survival advantage
• 4 (Very effective): Cure unlikely but sometimes provides long-term survival advantage
• 3 (Moderately effective): Modest impact on survival, but often provides control of disease
• 2 (Minimally effective): No, or unknown impact on survival, but sometimes provides control of disease
• 1 (Palliative only): Provides symptomatic benefit only

[S] Safety refers to the assessment of the relative likelihood of side effects from an intervention with fewer side effects being scored highly. The scale used to measure safety is:

• 5 (Usually no meaningful toxicity): Uncommon or minimal toxicities; no interference with activities of daily living (ADLs)
• 4 (Occasionally toxic): Rare significant toxicities or low-grade toxicities only; little interference with ADLs
• 3 (Mildly toxic): Mild toxicity that interferes with ADLs
• 2 (Moderately toxic): Significant toxicities often occur but life threatening/fatal toxicity is uncommon; interference with ADLs is frequent
• 1 (Highly toxic): Significant toxicities or life threatening/fatal toxicity occurs often; interference with ADLs is usual and severe
  Note: For significant chronic or long-term toxicities, score decreased by 1

[Q] Quality and quantity of evidence refers to the number and types of clinical trials relevant to a particular intervention. To determine a score, panel members may weigh the depth of the evidence, i.e., the numbers of trials that address this issue and their design. The scale used to measure quality of evidence is:

• 5 (High quality): Multiple well-designed randomized trials and/or meta-analyses
• 4 (Good quality): One or more well-designed randomized trials
• 3 (Average quality): Low quality randomized trial(s) or well-designed non-randomized trial(s)
• 2 (Low quality): Case reports or extensive clinical experience
• 1 (Poor quality): Little or no evidence

[C] Consistency of evidence refers to the degree to which the clinical trials addressing an intervention have consistent results. The scale used to measure consistency of evidence is:

• 5 (Highly consistent): Multiple trials with similar outcomes
• 4 (Mainly consistent): Multiple trials with some variability in outcome
• 3 (May be consistent): Few trials or only trials with few patients, whether randomized or not, with some variability in outcome
• 2 (Inconsistent): Meaningful differences in direction of outcome between quality trials
• 1 (Anecdotal evidence only): Evidence in humans based upon anecdotal experience

[A] Affordability refers to the overall cost of an intervention including drug cost, required supportive care, infusions, toxicity monitoring, management of toxicity, probability of care being delivered in the hospital, etc. with less expensive interventions being rated more highly than more expensive ones. The scale used to measure affordability is:

• 5 Very inexpensive
• 4 Inexpensive
• 3 Moderately expensive
• 2 Expensive
• 1 Very expensive

In cancer care, the most important value perspective is that of the individual patient. NCCN Evidence Blocks™ educate providers and patients about the efficacy, safety, and affordability of systemic therapy. NCCN Evidence Blocks™ are a starting point for shared decision-making based on a common vocabulary of choices and values. The NCCN Evidence Blocks™ are published in a new version of the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®) and are intended as a visual representation of five key value measures that provide important information about specific NCCN Guidelines® recommendations: efficacy, safety, quality and quantity of evidence, consistency of evidence, and affordability. Adding affordability to the existing National Comprehensive Cancer Network® (NCCN®) criteria for evaluating treatment options, empowers patients to identify, alongside their physician, optimal treatment based on clinical and economic considerations that are of most value to them. NCCN Guidelines with NCCN Evidence Blocks™ are an additional NCCN resource—separate from the NCCN Guidelines— that are currently available free of charge on NCCN.org.

For more information, visit NCCN.org/EvidenceBlocks.