OBJECTIVES: To assess physician beliefs on the relative benefits of pens vs. vials, prescribing drivers, and characteristics of patients newly initiated on basal insulin analog via pens vs. vials among elderly type 2 diabetes patients. METHODS: An online survey of 352 U.S. primary care physicians was used to collect retrospective patient chart data on 500 elderly type 2 diabetes patients who initiated on basal insulin analog in 2009. For each physician, patient chart selection was randomized among eligible patients. Data on physician characteristics, physicians’ opinion on the impact of different routes of administration (ROA), main drivers for selecting a particular ROA for each patient, and patient characteristics were collected.   RESULTS: The majority of physician respondents were part of a group practice (77.8%) and treated a mean of 235.5 (SD=185.0) type 2 patients ≥ 65 years old in 2009. Patient characteristics were similar in terms of age and diabetes duration. However, significantly more Caucasians (p = 0.011) and patients covered by Medicare only (p=0.015) were initiated on pens, whereas significantly more women (p=0.003), Black/African Americans (p=0.011), and dual eligible patients (Medicare + Medicaid; p=0.008) were initiated on vials.  Patients initiated on vials had higher median baseline HbA1c values (8.7 vs. 8.4, p<0.001).Survey findings suggested that physicians prescribed vials primarily due to patients’ economic constraints (62.9% of vial users vs. only 2.4% for pen users), although a majority of physicians considered pens better than vials (89.2% in terms of adherence, 65.1% in terms of HbA1c control, and 55.4% in terms of resource utilization). CONCLUSIONS: Results from this retrospective chart extraction survey suggest that patient characteristics differed between patients initiated on pens vs. vials, and that despite insulin pens being perceived as having better outcomes by physicians, economic considerations play a dominant role in the choice of insulin vials.