The GrowthMonitor app will calculate height data using smartphone images of children
taken by parents or carers in the home at two or more set time points. The app will
convert height data from the image to a numerical height measurement in centimeters and
this will be transferred to a central database hosted on a secure UK based server with
additional relevant demographic data (gender, ethnicity, weight, date of birth, and
parents' height).
The height and demographic data are transferred with an anonymous identifier to a
GDPR-approved secure database on a UK based server. Critically, patient images and
children's names will not be transferred, and only authorized users will have access to
the data stored within the secure database.
The app will display a virtual growth chart providing the patient with a digital history
of the child's growth over time. BMI will also be calculated and plotted on an age- and
gender-appropriate chart. Ultimately, users of the app will need to create an account
using a username (email address) and password. We will use their email address so that
password resets can be sent along with reminders or alerts about their account.
Child's height in relation to his/her parental heights as well as longitudinal growth
data will be analyzed within the secure UK based web server using existing growth
monitoring algorithms.
Height compared to population-based height references (HSDS)
Distance from target height (calculated from parental heights, THSDSDEV)
HSDS change over time (ΔHSDS) -when more than one height measurement is available
(taken >6 months apart)
Recorded heights will be compared with pre-established cut-off standards that define
normal growth in an appropriate population. We envisage being able to incorporate
ethnicity-matched reference population data as the app evolves. An automated outcome will
be returned to the parent/carer, via in app notification or email, and will offer advice,
for example, confirming normal growth or recommending appropriate medical contact.
Data will be stored in such a way that users can sync their old growth measurements on to
any new / replacement smartphone handset and also 'sync' any measurements taken offline.
An accurate standing height measurement will be obtained using a calibrated stadiometer
during a patient clinic visit. This 'gold standard' height measurement will be performed
by a trained member of the research team and documented. This will be used to compare
with the height obtained by the growth monitoring app in the clinic and subsequently at
home.