In PDC Group 1, 70.8%, 23.6%, and 5.7% of patients had consistently moderate adherence, high-then-low adherence, and continuously high adherence, respectively.
In PDC Group 3, 25.3%, 17.2%, and 57.5% of patients exhibited GBTM-defined consistently moderate adherence, moderate-then-low adherence, or high-then-low adherence, respectively.
Among the 172 children who had at least 2 adherence measures at study visits, 74 (43%) were consistently adherent, 3 (2%) were consistently non-adherent, and 95 555%) had patterns alternating between adherence and non-adherence.
The majority (20/27, 74%) of patients who continued to use cannabis over the 8-year follow-up period had consistently bad adherence, whereas only 17% (4/23) of the patients who stopped using cannabis were in the always bad adherence group.
Additionally, unexplained between-child variation remained in the final regression model, suggesting the presence of other unknown reasons why some children have consistently better adherence than others.
Patients with consistently moderate adherence had a lower mean age than the other groups (Table 3).
Chou and colleagues [ 33] reported benefits in Taiwanese children with ADHD (n = 137) who switched to OROS MPH (for ≥ 3 weeks) after exhibiting consistently poor adherence to at least 3 months' treatment with IR MPH.
While SES factors have not been consistently associated with adherence, we found a high asset index to be significantly associated with adherence.
Among the socio-demographic factors, age was the variable most consistently related to adherence; older patients were less likely to be adherent.
Adherence to long-term treatment regimes, particularly those involving behavioural components such as exercise, is consistently lower than adherence to medication [ 43].
