One Drop (OD) provides self-care support via an evidence-based mobile app, a Bluetooth-connected glucometer and testing supplies, and in-app coaching from CDEs. The app with coaching is associated with a 0.9 to 1.3% lab hemoglobin (A1c) improvement over 3 months. The full solution is associated with a 1.9% eA1c improvement over 3 months. We enrolled people with diabetes to participate in an IRB-approved study examining OD’s long-term effect on A1c. Adults with lab-verified ≥ 7.0% A1c and no prior OD account participated in a single-group longitudinal study. Participants used OD for an average 7.7 months. Lab A1c was assessed at baseline, 3, and 8 months. Descriptive statistics characterized the sample. Repeated measures ANOVA tested A1c change over time. Bonferroni-corrected post hoc tests examined A1c change between timepoints. Participants (N = 10) were 53 ± 7 years old and half female. Sphericity was assumed (Mauchly’s W = .30, p = .05). A1c significantly changed over time, F(2, 12) = 5.62, p < 0.019, partial eta = .48 (see Figure 1). When adjusted for multiple comparisons, baseline to 3-mo A1c change (MDiff = .64%, p = .10) and 3-mo to 8-mo Alc change trended significant (MDiff = 1.74 %, p = .10). Using OD for up to 8 months is associated with improved A1c. This is the first OD study to observe participants beyond 3 months and collect multiple measures of lab A1c over time. An accumulation of non-experimental and experimental evidence suggests OD improves A1c among people with diabetes.


A. Hirsch: Employee; Self; Informed Data Systems Inc. Research Support; Self; Fitbit, Inc., MannKind Corporation. Stock/Shareholder; Self; Informed Data Systems Inc. C.Y. Osborn: Employee; Self; One Drop. M. Heyman: Consultant; Self; Lexicon Pharmaceuticals, Inc., Lilly Diabetes, Tandem Diabetes Care. Employee; Self; One Drop. B. Huddleston: Employee; Self; One Drop. J. Dachis: Stock/Shareholder; Self; Informed Data Systems Inc.

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