title: Optimizing network connectivity for mobile health technologies in sub-Saharan Africa.
abstract: BACKGROUND
  Mobile health (mHealth) technologies hold incredible promise to improve healthcare delivery in resource-limited settings. Network reliability across large catchment areas can be a major challenge. We performed an analysis of network failure frequency as part of a study of real-time adherence monitoring in rural Uganda. We hypothesized that the addition of short messaging service (SMS+GPRS) to the standard cellular network modality (GPRS) would reduce network disruptions and improve transmission of data.
  
  
  METHODS
  Participants were enrolled in a study of real-time adherence monitoring in southwest Uganda. In June 2011, we began using Wisepill devices that transmit data each time the pill bottle is opened. We defined network failures as medication interruptions of >48 hours duration that were transmitted when network connectivity was re-established. During the course of the study, we upgraded devices from GPRS to GPRS+SMS compatibility. We compared network failure rates between GPRS and GPRS+SMS periods and created geospatial maps to graphically demonstrate patterns of connectivity.
  
  
  RESULTS
  One hundred fifty-seven participants met inclusion criteria of seven days of SMS and seven days of SMS+GPRS observation time. Seventy-three percent were female, median age was 40 years (IQR 33-46), 39% reported >1-hour travel time to clinic and 17% had home electricity. One hundred one had GPS coordinates recorded and were included in the geospatial maps. The median number of network failures per person-month for the GPRS and GPRS+SMS modalities were 1.5 (IQR 1.0-2.2) and 0.3 (IQR 0-0.9) respectively, (mean difference 1.2, 95%CI 1.0-1.3, p-value<0.0001). Improvements in network connectivity were notable throughout the region. Study costs increased by approximately $1USD per person-month.
  
  
  CONCLUSIONS
  Addition of SMS to standard GPRS cellular network connectivity can significantly reduce network connection failures for mobile health applications in remote areas. Projects depending on mobile health data in resource-limited settings should consider this upgrade to optimize mHealth applications.
authors.affiliation: Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA. msiedner@partners.org
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Siedner
authors.forename: Alexander
authors.initials: A
authors.lastname: Lankowski
authors.forename: Derrick
authors.initials: D
authors.lastname: Musinga
authors.forename: Jonathon
authors.initials: J
authors.lastname: Jackson
authors.forename: Conrad
authors.initials: C
authors.lastname: Muzoora
authors.forename: Peter W
authors.initials: PW
authors.lastname: Hunt
authors.forename: Jeffrey N
authors.initials: JN
authors.lastname: Martin
authors.forename: David R
authors.initials: DR
authors.lastname: Bangsberg
authors.forename: Jessica E
authors.initials: JE
authors.lastname: Haberer
mesh_terms: D000328:Adult; D040421:Cell Phone; D005260:Female; D040362:Geographic Information Systems; D006801:Humans; D008297:Male; D008875:Middle Aged; D010349:Patient Compliance; D013686:Telemetry; D014454:Uganda