Critical Flaws in the Validation of the Instant Blood Pressure Smartphone App—A Letter From the App Developers

To the Editor In a recent issue of JAMA Internal Medicine, Dr Plante and colleagues reported on the accuracy of the Instant Blood Pressure (IBP) app.¹ We identified misrepresentations and deficiencies in how the study and its analysis were conducted. Here we present our observations for consideration.

The authors failed to disclose that approximately 20% of their data were associated with reference blood pressures outside IBP’s supported measurement range. As published on the website² (data not peer reviewed) and App Store description prior to the start of the authors’ data collection, IBP will not produce estimates outside of its supported range (systolic, 102-158 mm Hg; diastolic, 65-99 mm Hg). We believe the authors’ failure to disclose or mention IBP’s supported range misled readers.