Table 1 Checklist for Modifying Disease Definitions [7]
Checklist Item | Rationale |
|---|---|
1. Definition: What are the differences between the previous and the new definition? | It is important to delineate the proposed change precisely. |
2. Number of people affected: How will the new disease definition change the incidence and prevalence of the disease? | The number of people affected is extremely important in understanding benefits, harms and resources needed. |
3. Trigger: What is the trigger for considering the modification of the disease definition? | Stating the trigger for considering modification helps understand the necessity for modifying the disease definition. |
4. Prognostic ability: How well does the new definition of disease predict clinically important outcomes compared with the previous definition? | The most important feature of a disease definition is its ability to accurately predict clinically important outcomes. |
5. Disease definition precision and accuracy: What is the repeatability, reproducibility and accuracy (when estimations are possible) of the new disease definition? | Disease definitions that are repeatable and reproducible improve the consistency of clinical decision making. Accuracy is often not able to be estimated because of the lack of a reference standard. |
6. Benefit: What is the incremental benefit for patients classified by the new definition versus the previous definition? | Benefits of the disease definition can be outlined, using methods such as GRADE. It is particularly important to estimate benefits in conditions where the new definition will be used to determine treatment thresholds. |
7. Harm: What is the incremental harm for patients classified by the new definition versus the previous definition? | Harms may also be outlined using methods such as GRADE. It is often more difficult to quantify harms, and particularly the psychosocial harms and harms on the societal level, including resource related harms. |
8. Net benefit and harms: What is the net benefit and harm for patients classified by the new definition versus the previous definition? | A panel should consider all the above, and the balance of net benefits and harms prior to modifying a disease definition. |