Standardization of definitions
We developed and validated standardized definitions for (non-)adherence/persistence to anti-vascular endothelial growth factor in the context of neovascular age-related macular degeneration (nAMD) treatment.
Find out more about this initiative and read our validated definitions. For more information about how the definitions were developed, click below to read our published article:
What was the aim of this initiative?
Increase awareness of the role and importance of adherence and persistence among healthcare professionals and patients
Set uniform parameters for future research
Tallow benchmarks to be established in order to measure the impact of future interventions
What are the validated definitions?
Full adherence
Attending every scheduled clinic appointment (treatment or monitoring), and undergoing every treatment or monitoring procedure advised by the treating physician over a
1-year period
Non-adherence
Missing two or more treatments or monitoring visits scheduled, as advised by the treating physician over a period of 1 yearb
Non-persistence
Not attending any treatment or monitoring visit for any reason for a period of 6 months,
OR
Follow-up appointments are not scheduled for any reason for a period of 6 monthsd
Adherence
Missing no more than one treatment or monitoring visit scheduled, as advised by the treating physician over a 1-year perioda,b
Persistence
Maintaining treatment or monitoring, as advised by the treating physician AND attending their most recent appointment within a 6-month periodc
Planned discontinuation or transfer of care
Planned discontinuation
Lack of treatment response (treatment futility) judged by the treating physician, OR
No disease activity requiring ongoing treatment judged by the treating physician
Transfer of care
The ongoing management of the patient’s nAMD is transferred to another physician
aA visit is considered to be missed if the recommended appointment date is exceeded by more than 2 weeks for any reason. The number of missed visits is determined based on the total potential visits missed during the period of non-adherence, using the last recommended visit interval.
bThe 1-year period begins from the first injection; for subsequent years of treatment, adherence is calculated every 1 year.
cA patient is not required to be adherent in order to be persistent.
dThe first day of the 6-month period after the most recent appointment attended should serve as the onset of non-persistence date. A minimum of a 6-month period since the first injection is required to assess persistence.