Should respiratory rate be measured on admission over a few seconds by a smartphone application or over 15 minutes by a piezoelectric device? A prospective observational pilot study of acutely ill medical patients admitted to a low-resource Ugandan hospital.

Background: the optimal period over which respiratory rate should be measured is uncertain.

Setting: medical ward of low resource Ugandan hospital, Methods: comparison of the first respiratory rates measured on admission over seconds using a smartphone application with measurements over 15 minutes using a piezoelectric device.

Results: There was a poor correlation between respiratory rates measured by the piezoelectric device and rates measured by a smartphone application. Although the discrimination for mortality of piezoelectric respiratory rates were slightly higher than those derived from the application, there were not statistically significant differences.

Conclusion: this study could not demonstrate potential clinical benefits that justify measuring the first respiratory rate after admission over 15 minutes by a device.