08 - Adherence measurement tools

Adherence measurement tools

© SPMM Course 6. Medication adherence  Compliance is defined as the extent to which a person’s behaviour coincides with medical advice. o Implies sole patient’s responsibility o Criticized as paternalistic.  Adherence includes the concept of patient choice: both clinician and patient share the responsibility for adherence. o In most research, definitions for adherence are usually dichotomous, but adherence is rarely an all-or-nothing phenomenon.  Concordance is based on the notion that the therapeutic alliance between the prescriber and patient is a negotiation process, with equal respect for both the patient’s and clinician’s agenda Adherence measurement tools  Self-report methods:  For example, using the Tablet Routines Questionnaire, which assess the daily routines for taking medication and the proportion of drug an individual has missed in the previous week and last month (Scott and Pope, 2002)  Pill counts  Adherence (%) can be calculated as (number of pills taken ÷ number of pills prescribed) × 100 (Azrin and Teichner, 1998)  Electronic methods  Electronic devices have been developed which can be attached to the tablet bottle. They record the time and date on every occasion that the bottle is opened  Prescription monitoring  The frequency of prescription dispensing for an individual can be monitored as a proxy measure of adherence  Saliva, plasma and urine assay tests  Most objective measures  Not available for all psychiatric drugs – expensive, invasive and have limited value in assessing partial adherence, leading to overestimate of adherence to long half-life drugs. Non-adherence rates are reported as 40–60% for antipsychotics, 18–56% for mood stabilizers and 30–97% (median 63%) for antidepressants. Nonadherent patients with schizophrenia are 3.5 times more likely than adherent patients to relapse within 2 years.