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The use of portable devices for data collection at home in clinical trials

Electronic data capture of patient data is increasingly replacing the use of paper-based diaries and electronic Clinical Outcomes Assessment (eCOA) tools are now routinely used for data capture in two situations: directly by the patient at home and during scheduled site visits.

Personal digital assistant (PDA) or ‘palm’ devices developed in the early 1990s were the forerunners to the introduction of Smart Phones and Tablets, with hybrid Phablet devices now available that combine features of both Smart Phones and Tablets.

Conventionally, Smart Phones are considered to be the best option for home use and Tablets are considered to be the best option for data collection during site visits. However, experience has shown that this convention is not necessarily a golden rule.

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Size of Tablet or Phablet screen vs Smart Phone screen

The larger screen offered by Tablet or Phablet devices is associated with better accuracy and compliance among most patient populations, improving the ease of use and interaction with the data collection software compared to using a Smart Phone. The larger screen improves readability and global layout and the increased size is particularly useful for visually impaired patients.

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The main advantage of a Smart Phone for data collection at home is its portability. However, for most clinical trials, data entry by the patient at home is only required once or twice per day, usually in the morning and/or evening, and it is not necessary for a patient to carry a device around all day; only occasionally is more frequent data entry required by the patient, in which case the portability of a device becomes more important. As such, the better portability of a Smart Phone is offset by the larger screen size of a Tablet or Phablet, and so the larger devices should be given greater consideration for home use.

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A single device in all situations

A further advantage of using a Tablet or Phablet for both home use and during study visits is that the same device can be used in both situations, which harmonizes the training of clinical site staff and patients and simplifies inventory management.

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BYOD is currently limited

The use of a ‘bring your own device’ (BYOD) approach, in which the patient’s own device is used for electronic data collection via downloaded applications, is likely to become more important in the future. However, this approach is currently limited due to regulations regarding the harmonization of data collection using different devices.


In summary, there are arguments in favor of using the same Tablet or Phablet for data collection both at home and during site visits. While this does not preclude the more conventional use of Smart Phones at home, the experience of Kayentis in eCOA management and data collection suggests numerous advantages for patients and sponsors, as well as improved data quality, when Tablets or Phablets are used in both situations.

You can also take a look at our article about how to use a tablet device at home for clinical trials.

Guillaume JUGE, CEO – Kayentis

Last update : 22 January 2018


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