Core concepts in pharmacoepidemiology: Measures of drug utilization based on individual‐level drug dispensing data

Abstract

Background Drug utilization studies are essential to facilitate rational drug use in the society. Aim In this review, we provide an overview of drug utilization measures that can be used with individual‐level drug dispensing data, referencing additional reading on the individual analysis. This is intended to serve as a primer for those new to drug utilization research and a shortlist from which researchers can identify useful analytical approaches when designing their drug utilization study. Results and Discussion We provide an overview of: (1) basic measures of drug utilization which are used to describe changes in drug use over time or compare drug use in different populations; (2) treatment adherence measures with specific focus on persistence and implementation; (3) how to measure drug combinations which is useful when assessing drug–drug interactions, concomitant treatment, and polypharmacy; (4) prescribing quality indicators and measures to assess variations in drug use which are useful tools to assess appropriate use of drugs; (5) proxies of prescription drug misuse and skewness in drug use; and (6) considerations when describing the characteristics of drug users or prescribers.

Comparative cardiovascular safety of romosozumab versus bisphosphonates in Japanese patients with osteoporosis A new-user, active comparator design with instrumental variable analyses

“…However, at least the duration of exposure to osteoporosis medications was appropriately defined through the implementation of the refill-gap method, which is standard in pharmacoepidemiologic studies, and through the specification of a clinically plausible grace period. 14 To account for imprecisions in the diagnostic terms, the definitions of outcome variables and comorbidity variables in this study were defined based on the findings of previous validation studies. For example, the definition of CVD based on a combination of disease/procedure codes, medications, as well as testing, guarantees a high positive predictive value for true CVD events.…”

“…This was a cohort study using a new-user, active comparator approach. 14,15 Patients who met all of the following four criteria were included: (1) age ≥ 40 years; (2) ICD-10 code "osteoporosis with/without pathological fractures" or experiencing fragility fractures 16 ; (3) new prescription of either romosozumab (WHO-ATC code: M05BX06) or bisphosphonate; and (4) prescription date later than March 4, 2019 ( eTable 1) . Patients whose diagnosis code included "suspect" were excluded.…”

“…This was a cohort study using a new-user, active comparator approach. 14,15 Patients who met all of the following four criteria were included: (1) age ≥ 40 years; (2) ICD-10 code "osteoporosis with/without pathological fractures" or experiencing fragility fractures 16 ;…”

Evaluating the Effect of Inequalities in Oral Anti-coagulant Prescribing on Outcomes in People with Atrial Fibrillation

“…Discontinuation of anti-coagulation was established according to the refill-gap method; those with a temporal gap between consecutive prescriptions of greater than sixty days, not filled by the penultimate prescription, were defined as having discontinued. (14) Prescriptions of oral anti-coagulants were determined from the PIS; this dataset comprises records for all prescribed drugs dispensed by community pharmacies, in addition to dispending physicians and suppliers of medical devices. (15) To ensure that the indication for the anti-coagulant prescription was exclusively AF, Individuals with valvular heart disease, a mechanical cardiac valve, or venous thromboembolism, were excluded from analyses (Table S3).…”

Psychotropic Medication Prescribing for Children and Adolescents After the Onset of the COVID-19 Pandemic

“…Use of psychotropic medications is often considered a proxy for the mental health status of a population or for the prevalence of specific mental disorders . Population-based studies have reported increases in the uptake of antidepressants and hypnotics among youths (<18 or 19 years) in the months following the pandemic onset .…”