Rigor and equity in intervention study design in pediatric psychology: a focus on comparator conditions from diabetes research.

Inhalers are the cornerstone of pharmacologic treatment for COPD and asthma. However, choosing the right inhaler is complex. Optimal selection depends not only on the pharmacologic agent and inhaler delivery device but also on disease severity, cost, and patient factors that facilitate or complicate inhaler use such as manual dexterity or visual impairment. Inhaler selection is further influenced by formulary-driven changes that may compel patients to switch to a different medication or device. Non-medical formulary changes (ie, those made for administrative or cost-related reasons rather than patient need) can disrupt personalized care and adversely affect clinical outcomes. Several studies have linked non-medical inhaler switches to worse asthma control, decreased lung function, and increased health care utilization. A 2022 systematic review examined the real-world consequences of inhaler regimen changes not driven by clinical need. The review found variable clinical outcomes, ranging from no significant effects to marked declines in disease control, particularly among patients with asthma. However, the authors highlighted heterogeneity in study designs, populations, and outcome measures, which limited the generalizability of the findings. Few of the included studies assessed implementation processes or patient and provider experiences, factors likely to influence the success or failure of such transitions. In 2021, the Veterans Health Administration (VHA) implemented a nationwide formulary change, replacing the budesonide-formoterol metered-dose inhaler (MDI; Symbicort HFA, AstraZeneca) with a fluticasone-salmeterol dry-powder inhaler (DPI; Wixela Inhub, Viatris). In a self-controlled case series and matched observational cohort study of approximately 260,000 veterans, Rabin et al found that the transition was associated with increases in both all-cause and respiratory-related emergency department visits and hospitalizations among those who switched inhalers. Veterans switched to fluticasone-salmeterol DPI also had increased rates of rescue medication use, reflected by increased prednisone prescriptions. Although these findings suggest potential harm, the study did not explore how the formulary change was implemented or which factors may have contributed to the observed outcomes.