Rehabvisual: Validation of an Application to Stimulate Visuomotor

Skills in Preterm Babies with Developmental Alterations

Catarina Santos

, Ana Ferreira

2,3

, Cláudia Quaresma

1,4

and Carla Quintão

1,4

Departamento de Física, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa,

2829-516 Caparica, Portugal

Serviço Medicina Física e Reabilitação, Hospital de D. Estefânia, Centro Hospitalar de Lisboa Central,

1169-045 Lisboa, Portugal

Departamento de Saúde, Escola Superior de Saúde, Instituto Politécnico de Beja, 7800-111 Beja, Portugal

LIBPhys - UNL, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal

Keywords: Rehabilitation, Visuomotor Skills, Pediatrics.

Abstract: The methods of evaluation and intervention related to the visuomotor skills, for children under the age of 18

months with neurological dysfunctions are not systematic and individualized. Hence, the RehabVisual

platform was developed. The aim of this article is to present the usability tests applied to the platform

validation, as well as describing the application of the platform in the therapy sessions of a baby with a clinical

diagnosis of prematurity. The study concludes that the application of the platform allows the treatment to be

more individualized and specific to the baby needs through a common method to all service. Through usability

tests, it was possible to ascertain that at the level of occupational therapy, this is a useful tool adapted to the

needs of its users.

1 INTRODUCTION

The RehabVisual platform was developed with the

objective of stimulating the visuomotor competences

in children up to 18 months with developmental

alterations resulting from preterm birth (Machado et

al., 2018). The platform allows to adapt the therapies

to the needs of infants and the assessment of their

performance over the course of the treatments.

Preterm babies have a higher probability of

developing complications related to organ system

immaturity and a higher risk of developing ocular

problems. So early stimulation is very important,

improving the capacity of fixation, follow-up, and

oculomotor coordination. This recovery can be

justified by the fact that during the first year of life

some processes of maturation in the brain still occur,

this period is called cerebral plasticity and allows an

adaptation and modification of the brain according to

the stimuli present (Alimovic, 2012).

The main objective of this article is to describe

and analyze the application of usability tests related

to the platform performed by occupational therapists.

As an example, a case of the application of the

intervention program to a child under the age of 18

months and with developmental alterations resulting

from preterm birth will be analyzed.

Usability tests are used in order to understand

whether the product developed takes into account the

needs of its users, not focusing only in the

functionalities of the same.

According to ISO 9241-11 (1998) the usability of

a product should ensure that a specific user can use it

in order to achieve its goals in a manner that is

efficient and with satisfaction in a given context of

use. These three concepts are defined as:

1. Effectiveness: is the precision capacity with

which the user completes his/her tasks

interaction with the application;

2. Efficiency: is the amount of resources

(cognitive, physical effort, and time) that the

user needs to carry out a task in order to obtain

a positive result;

3. Satisfaction: Evaluates the degree of

contentment that the user demonstrates during

the interaction with the application.

More recently, ISO 9126-1 (2003) defines

usability as the capacity of the product software to be

understood, learned, operated and attractive to the

user, when used under specific conditions. Thus,

applications are intended to be user-friendly and

attractive to their users, which influences their

adoption and their use in a common way.

248

Santos, C., Ferreira, A., Quaresma, C. and Quintão, C.

Rehabvisual: Validation of an Application to Stimulate Visuomotor Skills in Preterm Babies with Developmental Alterations.

DOI: 10.5220/0007567102480255

In Proceedings of the 12th International Joint Conference on Biomedical Engineering Systems and Technologies (BIOSTEC 2019), pages 248-255

ISBN: 978-989-758-353-7

To ensure that the technological solution

developed is useful and that captivate the end user to

include it in its daily tasks there are a set of steps that

are necessary to fulfill. These steps include conducting

surveys during the development phase, in order to

understand the needs and preferences of users and to

explore solutions that improve the quality of user

interaction and the application. After the development

phase, usability tests are applied with the purpose of

verifying whether the application is in accordance with

the requirements previously identified (Lyles et al.,

2014), (Kushniruk and Patel, 2004).

Usability questionnaires are a source of collection

of opinions and suggestions that allow the researchers

to assess certain aspects of application interaction and

usability. There are a set of questionnaires already

applied in the field of health applications, the most

used being the Post-Study System Usability

Questionnaire (PSSUQ) and the System Usability

Scale (SUS).

Regarding the health area, the developed

applications have specific characteristics that limit

their usability. Among which, the use of small

screens, with reduced font sizes, which can limit the

interaction between the user and the application and

there are applications that need to be permanently

available so as not to compromise the health of

patients (Zhou et al., 2017).

The integration of usability assessments also

allows the reduction of costs and time associated with

product changes after its development, since the

entire production process is carried out based on the

preferences of the end user (Johnson et al., 2005).

2 MATERIALS AND METHODS

2.1 Platform

The RehabVisual platform intends to accompany the

entire rehabilitation process of the baby, by

integrating the evaluation components and including

an intervention program to be used as a complement

to the therapy sessions. RehabVisual is adaptable to

the needs of each baby, or customized. It was built

taking into account five different types of users:

administrator; doctor; technician; occupational

therapist and care provider, corresponding to the

person accompanying the baby in the consultations

and sessions (Machado et al., 2018).

Regarding the functioning of the platform, a

record of the clinical information of the patient is

performed, which can subsequently be associated

with ophthalmologic assessments, behavioral,

functional assessments and response to the sessions

of Intervention Program.

The evaluation is performed as follows: in the

ophthalmologic evaluation the functioning of both

eyes and the visual system is described and in the

behavioral assessment it is intended to perceive the

way the baby uses the vision in performing tasks, the

level of focus of objects, visual attention and

visuomotor coordination (Alimovic, 2012). The

functional assessments and the intervention program

are based on the baby's response to a set of stimuli

available on the platform.

The stimuli developed allows the user to have a

wide range of options with different levels of

complexity in order to stimulate the child. This

stimulus is adaptable according to its evolution and in

order to decrease the probability of habituation and

consequent disinterest (Corn and Erin, 2010).

The evaluation of both the intervention program

and the functional evaluation is based on indicators

such as looking, smiling or balancing. The intention

was to perceive the fixation and persecution capacity

in relation to the stimuli to which the baby was

exposed.

In these assessments, it was adopted an evaluation

scale used in visual assessments (Machado et al.,

2018). The scale consists of the following parameters:

1. Never - (0%)

2. Rarely - (25%)

3. Occasionally - (50%)

4. Often - (75%)

5. Always - (100%)

In all assessments there is also the possibility of

inserting comments that allow the user to add relevant

information to the baby's condition.

2.2 Usability Questionnaire

The SUS questionnaire was used as part of this study.

This questionnaire consists of a set of 10 items in

which the participant should score them in a one to

five scale according to the level of agreement. The

fact that it is based on positive and negative

assertions, in which the participant has to classify

them with their level of agreement, makes the

participant more alert leading to more consistent

results in small population samples (Albert and Tullis,

2010). The choice of this protocol was made because it

is reliable, versatile, simple and with a reduced number

of parameters questionnaire. The latter being

extremely important as users testing the platform could

not be available to respond to longer questionnaires. In

addition, the final score obtained through this

questionnaire is easy to interpret (Klug, 2017).

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249

Regarding the number of participants required to

ensure the validation of the usability tests, according

to the bibliography, there are at least five people,

allowing with this number of people to identify about

85% of possible problems, not at risk of appearing the

same type of error several times (Nielsen Norman

Group, 2012).

2.3 Platform Validation

The usability tests were performed at the Physical

Medicine and Rehabilitation (MFR) Service of

Hospital D. Estefânia (HDE). Additionally, they were

performed on occupational therapists from the

Rehabilitation Medicine Center of Alcoitão.

The script used during the tests describes a

scenario to simulate the use of the platform in the

context of therapies and consists of several tasks that

will be implemented by users in the context of the

therapies. The study was approved by the Central

Hospital of Lisbon (CHLC) Ethics Committee.

2.3.1 Participants

The usability tests were performed by nine

occupational therapists, four from the MFR Service

of HDE and the remaining five from the

Rehabilitation Medicine Center of Alcoitão. Only two

of the HDE service participants had already been in

contact with the platform during therapy sessions

with the baby test group with development changes

and less than 18 months, having already made some

suggestions for changes during the development

phase of the platform.

2.3.2 Test Protocol

The test session is of an individual character and it is

initiated with a brief introduction to the platform, then

it is requested the user to perform the tasks indicated

in the protocol. Two protocols were elaborated with

tasks, one of larger extension for occupational

therapists of HDE and a shorter one for occupational

therapists of the Rehabilitation Medicine Center of

Alcoitão, due to the limited time they had to perform

usability testing.

In the larger protocol, there are various tasks

performed by occupational therapists since the

patient's registration, until the insertion of functional

assessments and intervention sessions, where it is also

requested to consult and edit previously submitted

assessments. In the shorter protocol, only the patient

form and the intervention program are approached,

which are the most used by occupational therapists.

2.3.3 Evaluation of the Test Protocol

The degree of user satisfaction is assessed throughout

the test session (at the end of specific tasks) and in a

more global way at the end of the protocol, through

the completion of the SUS questionnaire.

Additionally, participants can give their opinion and

suggestions for improvement.

Over the course of the session, the user is asked

about the ease of insertion, edition and research of data

regarding the patient's clinical record and assessments.

In the SUS questionnaire, the user's opinion is

requested on ten statements, each of which with five

hypotheses of response that go from "strongly

disagree" to "strongly agree". The assertions are:

1. I think I'd like to use this system often.

2. The system is unnecessarily complex.

3. I think the system is easy to use.

4. I think I need help from a technician to be able

to use the system.

5. I thought the various functions of this system

were well integrated.

6. I thought there were a lot of inconsistencies in

the system.

7. I imagine most people can learn to use the

system quickly.

8. I found the system very complicated to use.

9. I felt very confident using the system.

10. I need to learn many things before using the

system.

2.4 Use of the Platform in the Therapy

Sessions

The platform was also included in the occupational

therapy sessions of six babies up to 18 months of age

with developmental changes resulting from preterm

birth, performed by two occupational therapists

included in the validation of the platform.

Informed consent was requested to all parents, and

after their authorization, the use of the platform was

initiated in the occupational therapy sessions. The

choice of stimuli to be used in each session was

performed taking into account the analysis of the

occupational therapist of the baby's behavior in the

previous session and during the stimuli visualized

throughout the session, which allows to have a

personalized treatment for the needs of each baby. In

other words, the choice of stimuli is made taking into

account the evaluation of the acquisition of compe-

tencies by babies and not according to their diagnosis.

The platform was complemented by the therapy

sessions already attended at the HDE of MFR service,

and the number of sessions in which it was applied,

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Table 1: SUS results.

Participant/affirmation 1 2 3 4 5 6 7 8 9 10

SUS

results

Participant 1 4 4 3 4 5 1 3 3 3 3 57,5

Participant 2 4 1 5 1 5 2 5 1 4 1 92,5

Participant 3 2 3 3 3 3 2 2 3 2 4 42,5

Participant 4 5 1 5 2 5 2 4 1 4 2 87,5

Participant 5 4 2 4 2 4 2 5 1 4 4 75

Participant 6 4 2 4 2 5 1 4 1 4 1 85

Participant 7 3 1 5 2 4 3 4 1 3 4 70

Participant 8 3 2 5 2 4 1 5 1 4 2 82,5

Participant 9 5 1 5 4 5 1 4 1 4 1 87,5

SUS mean score 75,6

Confidence interval (95%) 12,63

which depended on the number of weekly therapy

sessions of each baby.

3 RESULTS

3.1 Usability Test

3.1.1 Results

Knowing that in the SUS questionnaire half of the

statements are of a positive nature and the remaining

negative ones, it is necessary to convert them into a

single result, as well: in the questions associated with

the odd number (positive questions) the answer is

subtracted by the value of 1 and in the questions

associated with the even number (negative questions)

the answer is subtracted by the value of 5. The values

are then summed, and this result is multiplied by the

value 2.5 in order to generate the SUS score, which is

between 0 and 100 (McLellan et al., 2012). The

average SUS score is 68, which corresponds to the

percentile. This score is affected by the

complexity of the system and the tasks that the user

has to perform (Klug, 2017).

A color map was used in table 1 in order to more

easily identify the positive responses so in the case of

the assertions of positive character the values 4 and 5

are marked green, the 3 is identified in yellow and 1

and 2 in orange. In the case of negative responses, the

representation is assigned inversely, as such the green

color is assigned to the scores of 1 and 2, the yellow

color is assigned to 3 and the orange color to scores

of 4 and 5 (McLellan et al., 2012).

With regard to participants, participants 1, 2, 3

and 4 correspond to the therapists of the HDE´s MFR

service who were already aware of the platform

before the day they performed the usability test,

although only two had used the platform in

occupational therapy environment. The remainder

correspond to the occupational therapists of the

Rehabilitation Medicine Center of Alcoitão, who

were only aware of the platform on the day they

performed the usability test.

Participants 1 and 4 followed the use of the

platform throughout the occupational therapies of the

test group.

From the analysis of the table 1 it is concluded

that the assessment made by users is generally

positive, and only two users (participant 1 and 3)

rated the platform negatively (SUS value less than

68). It should be noted that only participant 3 shows

a very negative result (SUS value less than 51). Of all

the participants with positive results, two classify the

platform as good (SUS value higher than 68 and less

than 80.3) and the remainder as excellent (SUS value

exceeding 80.3) (UX research, 2017).

The two participants with a SUS rating of less

than 68, during the test both stated that they do not

often use the computer which may have compromised

the answers given in the questionnaire.

The participants who have a positive SUS value,

participants 5, 7 and 9 present the following

justifications for the statements of the questionnaire

on which they disagree (presented in the table with

the orange color):

1. Participant 5, in statement 10 agrees that he

needs to learn many things before using the

system, justifying that the answer was given

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251

not because he needs to learn many things in

the perspective of using the system, but in the

area of ophthalmology and problems

including assessments, intervention and

problems. The reason that leads to this

response may be related to the fact that this

participant did not have knowledge of the

project before the day of the usability test,

another possible reason was the fact that the

Participant belonged to the group that held a

more summarizing task protocol not

addressing all available menus on the

platform.

2. Participant 7 presents the same opinion as

participant 5 in the statement 10, having

justified the answer given in the same way.

Additionally, he also justifies the answer

given in statement 6 where he does not agree

or disagree with the assertion: "I found that

there are many inconsistencies in the system"

clarifying that although he does not detect

inconsistencies in the system itself, he

considers very important that the

criteria/conditions under which the

stimulation program should be applied is

defined, so that the results of system

assessments are

3. reliable.

4. Participant 9 only negatively classifies claim

4: "I think I need help from a technician to be

able to use the system ", justifying that this

help would be for an initial phase of use.

In general, it appears that the statements that have

caused more negative results were the statements 4

and 10, which can be explained by being people who

did not feel comfortable using technological

applications or to being part of the participants who

had no prior knowledge of the project.

3.1.2 Suggested Alterations

The changes suggested by the participants are mainly

centered on the aesthetics of the platform, especially

in the increase of the size of the letters and the colors

used in order to contrast more with the background.

Additionally, it was suggested to change the name of

some buttons in order to be more intuitive.

3.2 Example of a Participant in

Therapy Sessions

This article describes the application of the

intervention program in one of the participants in a

detailed manner.

The participant is male, aged 8 months at the

beginning of the study. It presents a clinical diagnosis

prematurity of 31 weeks and very low birth weight

(1020g). In the application of stimuli throughout all

sessions, the baby was in a room where there were no

other therapies taking place (which caused no noise)

and no adjustments were made to the luminosity of

the room.

In the first session, the black and white

stimulation program was applied, with the highest

contrast. In this session, it was analyzed the number

of videos that could be visualized without showing

signs of fatigue. In the protocol used a gradual

increase of the complexity of the videos was made,

they were visualized simple videos (with a single

figure) of the 4 figures established (circle, square,

triangle and mixed pattern) and one of the patterns of

minor complexity of the circular form (figure 1). The

baby showed signs of fatigue in the video with the

pattern, which is why the intervention program was

interrupted.

Figure 1: Examples of the videos used on the first session

(triangle simple video and pattern with minor complexity).

In the second session, four days later, the program

is adapted to the baby's response, a simple figure

video and a smaller complexity pattern in black-and-

white protocol was repeated. The choice of the videos

was made to confirm the consistency with the

previous session. The baby's answer in the simple

figure videos continued to be the maximum of the

scale, the response to the video with a smaller pattern

of complexity was slightly inferior.

In the third session, one week later, as the baby

had greater basic motor agitation, it was decided by

the therapist that it would not increase the level of

difficulty of the videos in relation to the previous

sessions.

In the fourth session, three days later, the behavior

of the baby remained agitated, the lower complexity

pattern stimuli were again introduced, in the black

and white protocol. However, the answer in this

category was better than in the previous session.

Therefore, a video of greater complexity with

movement was introduced with the aim of stimulating

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the baby (figure 2). In this video the baby only kept

the attentional focus in the larger figure.

In the fifth session, four days later, in addition to

the colors black and white the red color was

introduced. The simple stimulus was resumed, since

when introducing, in the previous session,

Figure 2: Fourth session, introduction of horizontal

movement with circular form.

the videos with movement (which correspond to the

videos of greatest demand) there was a decline in the

provision of the baby. So, it was attempted to realize

if starting with a video of inferior requirement to the

first visualized in the previous session, the installment

in the videos with motion would be better. There was

a slight improvement in the video with horizontal

motion although he had not kept the focus all the time.

The introduction of the red color was made in the last

video (diagonal movement with slow speed), in order

to stimulate the baby who begins to recognize this

color around 2/3 months of age, although the baby

never pursued or fixed the stimulus, which can be

justified by being a too demanding video for the baby

or for the stipulated time, not to be adjusted to the

attentional capacity of the baby (figure 3).

Figure 3: Fifth session, diagonal movement.

In the sixth session, two weeks and three days

later, stimuli of the black-and-white and color-

colored protocol were performed. Only medium

speed videos for horizontal movement (circular

figure) and fast speed (diagonal movement of mixed

pattern with fast speed) were used in order to verify

that the loss of attentional focus in previous sessions

was due to the speed of movement. The introduction

of the mixed pattern had the objective to perceive

whether with the change of figures during the video,

the baby was able to regain attentional focus. The

baby's visual response to the horizontal motion video

was better than in the diagonal motion video,

although in both, an improvement was registered in

relation to previous sessions.

In the seventh session, a week and four days later,

videos of the program of red color and blue color were

visualized. In this session we only opted for motion

videos with fast speed (vertical movement of fast

speed, fast diagonal movement with mixed pattern

and circular movement with fast speed). The choice

of the vertical motion video was made for being a

movement with a degree of complexity similar to that

of the horizontal movement and thus be able to

change the simplest stimulus introduced in this

session, since the horizontal motion video was

presented during three consecutive sessions. The red

color in this video was used instead of the blue color

subsequently were introduced two more complex

videos and so the red color allows to make the initial

stimulus easier because it is the first color recognized

by the baby. In vertical motion the baby pursued and

always fixed the stimulus (figure 4). In the diagonal

Figure 4: Seventh session, vertical movement.

movement, even though the fast speed video was

introduced. It is concluded that it is too long for the

baby to be able to visualize without losing its

attentional focus. For the circular motion the baby

pursued all the figures presented occasionally, but

lost the attentional focus along the movement of the

same figure (figure 5).

Figure 5: Seventh session, circular movement.

In the eighth session, a week and three days after

the previous, were only chosen videos of the blue

color program. The standard videos with medium

complexity of mixed pattern (video of less

complexity for this session) and the diagonal motion

with fast speed of mixed pattern were selected.

In the video with medium complexity pattern, the

baby occasionally pursued, altering the attentional

focus between the various figures presented in

although not during the entire time of the pattern

display. When the pattern altered, he regained

attentional focus. In the diagonal movement, he

pursued and focused only part of the movement of

each of the figures, not being able to follow any of the

movements to the end.

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253

Figure 6: Results of the patient (fixation and following capacity) during therapy sessions.

Generally speaking, during the sessions, it is

concluded that the parameter of fixing the stimuli is

the one that presents the best results, which on one

hand can be explained by initially the baby acquire

the ability to fix and only after the ability to pursue an

object. It is also noted that in relation to simple

figures, the baby always has a very positive response

throughout the sessions. In the videos with medium

complexity, the response was also generally

improving as they were being inserted in the

therapies. In relation to stimuli with movement it is

concluded that the most adjusted to the baby are the

medium and fast speed, although in the case of videos

with diagonal motion these two speeds need to be

misadjusted to the baby's attention period (figure 6).

4 CONCLUSIONS

Through the usability tests it was possible to ascertain

that at the level of occupational therapy, this is a

useful tool and is adapted to the needs of its users

(since the average result of the SUS questionnaire and

the result of the questions made after the performing

the tasks were positive). However, it is necessary to

pay attention to the sample of the platform users, to

what people who are not familiar with computer tools

might sense in the introduction of the application on

their work.

At the level of therapy sessions, the tool is quite

versatile since new stimuli can be easily introduced

more adapted to the needs of the infants and their

ages, making the treatment more individualized and

specific to the population in question.

Currently, the included stimuli already provides

a very wide choice that allows the therapist to adapt

the sessions according to the baby's response

throughout the treatment so that no signs of

habituation arise or that the level of difficulty is

misadjusted to the baby.

The platform also allows obtaining a

standardized evaluation that facilitates registration,

as well as the subsequent interpretation of the results

during the real-time monitoring of the baby along

the treatment so that it can always be adapted

whenever possible.

5 FUTURE WORK

As future work it would be interesting to add an eye

tracker to the platform in order to verify if the infant

is really fixating or pursuing the image, which would

make the assessment easier and more correct.

ACKNOWLEDGEMENTS

The authors would like to thank all the healthcare

professionals of the Physical Medicine and

Rehabilitation Service at D. Estefânia Hospital.

Evaluation per Session: Abilit

to fix and follow

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