title: Basal Temperature Measurement Using a Multi-Sensor Armband in Australian Young Women: A Comparative Observational Study.
abstract: BACKGROUND
  The menstrual cycle is a key marker of health in women of reproductive age. Monitoring ovulation is useful in health studies involving young women. The upward shift in basal body temperature, which occurs shortly after ovulation and continues until the next menses, is a potentially useful marker of ovulation, which has been exploited in clinical and research settings.
  
  
  OBJECTIVE
  We investigated the utility of BodyMedia SenseWear (BMSW) in monitoring ovulation in young women by analyzing the correlation and agreement of basal temperatures measured using BMSW and a digital oral thermometer.
  
  
  METHODS
  Kappa statistics were used to determine the agreement in ovulation detection between the two devices, for each participant, under each form of analysis. Participants also completed an online questionnaire assessing the acceptability of both devices.
  
  
  RESULTS
  We recruited 16 participants with 15 of them providing analyzable data (11 OCP non-users, 4 OCP users). Weak to moderate correlations were observed between thermometer and BMSW temperature measurements averaged over 5 different time intervals. However, no agreement between methods was observed using Bland-Altman plots. There was a significant difference in the range of temperatures that each device recorded (thermometer: 35.3-37.2°C, BMSW: 29.7-36.7°C) with BMSW temperatures significantly lower than thermometer temperatures: mean 34.6°C (SD 1.2) versus 36.4°C (SD 0.3) respectively, P<.001. Poor agreement was observed between devices under quantitative analysis of ovulation while fair agreement was observed under visual analysis. Under both quantitative and visual analysis, there was 0% agreement for evidence of ovulation.
  
  
  CONCLUSIONS
  This study demonstrated the importance of evaluating biomeasures collected using mobile monitoring devices by comparison with standard methods. It revealed a relatively poor correlation between BMSW and oral thermometer temperature readings and suggested that BMSW is unlikely to detect an upward shift in basal body temperature. Participant behavior suggested poor compliance in the use of BMSW for basal temperature measurement and that the basal body temperature method may not be suitable for use in unselected samples of young women. There is a need for research tools for monitoring ovulation that are simple, self-administered, and inexpensive, yet appealing to young women.
authors.affiliation: University of Melbourne, Department of Medicine, Royal Melbourne Hospital, Parkville, Australia. jdwark@unimelb.edu.au.
authors.forename: John D
authors.identifier: http://orcid.org/0000-0003-2431-7902
authors.initials: JD
authors.lastname: Wark
authors.forename: Lucy
authors.identifier: http://orcid.org/0000-0003-0143-2270
authors.initials: L
authors.lastname: Henningham
authors.forename: Alexandra
authors.identifier: http://orcid.org/0000-0003-1032-0457
authors.initials: A
authors.lastname: Gorelik
authors.forename: Yasmin
authors.identifier: http://orcid.org/0000-0001-5975-9378
authors.initials: Y
authors.lastname: Jayasinghe
authors.forename: Stefanie
authors.identifier: http://orcid.org/0000-0001-6754-6903
authors.initials: S
authors.lastname: Hartley
authors.forename: Suzanne Marie
authors.identifier: http://orcid.org/0000-0002-6869-311X
authors.initials: SM
authors.lastname: Garland
keywords: BodyMedia SenseWear; basal body temperature; menstrual cycle, young women; ovulation; young female health initiative