Introduction

Mobile health (mHealth), or the use of mobile devices in medicine and health, is a sub-category of eHealth1. Health interventions are designed to improve healthcare services, and they may be divided into different areas, including medical records and communication2,3. We find three main applications. Mobile electronic health records (EHRs) used by healthcare professionals. Personal health record applications that patients can use to examine and control their own health data. And applications that allow direct patient control over records of specific diseases. The use of EHRs is expected to lead to improved efficiency, better communication, improved accessibility, and enhanced quality of care4,5,6,7. These services and applications that utilize mobile functionality are actively being developed in hospitals, organizations, and other groups8,9,10,11,12.

Several research studies have been performed on mHealth applications, and the results have indicated that well-designed mHealth applications can empower patients, improve medication adherence, and reduce the cost of health care13,14. To assess and improve upon the usability of mHealth applications, a wide range of usability evaluation methods (UEMs) are available to detect problems in user–system interaction. Employing multiple methods enables a more comprehensive assessment of the usability of eHealth interventions than using a single evaluation method15. The UEMs allow the identification of those facets of the interaction that need improvement16,17,18. To determine the usability of any new technology, appropriate and rigorously developed measures must be employed19,20,21,22. Although the use of mHealth has increased rapidly in recent decades, there is limited scientific evidence supporting its effectiveness23,24,25,26,27,28,29, possibly because of a lack of reliable information regarding proven benefits30,31.

Study context

The mobile health-app that is the focus of this study, AppADIm (Mobile Integrated Healthcare at Home), was originally developed with the aim that the health professionals (doctors and nurses) of home hospitalization units could have secure access to patients’ relevant medical information as clinical notes, records of vital signs and medical orders. Record follow-up data at home, and automatically upload data to the hospital EHR, thereby saving the professionals’ time and avoiding transcription errors. Our previous study results on the developed AppADIm observed that 86% of the professionals used it on a regular basis and considered it an improvement for their daily work. The total theoretically saved hours in medical information transcription were 256 per year, which would correspond to 36.5 days (7-h shifts). The conclusion was that using an application to consult and update a patient’s health record at home avoids transcription errors and saves professionals’ time32. AppADIm has been evolucionating during the last years and a second version is currently in use. Although the mobile application represents an important advance and an improvement in the care provided by professionals, it is currently not being used homogeneously by all health professionals and, consequently, paper documentation is still being used during home visits. This means that patient data and records continue to be duplicated, which is a waste of time and does not sufficiently improve clinical practice or patient safety.

The aim of this study was to assess the acceptability and usability of the AppADIm for health professionals working with patients’ electronic records at home and to suggest further improvements to the application.

Methods

Study design

In this study, different methodologies and techniques were used to evaluate the acceptability and usability of the mobile application, which is already described in the literature31,32,33. Usability is defined as “the extent to which a product can be used by specific users to achieve specific goals with effectiveness, efficiency and satisfaction in a specific context of use”34. Acceptance, for the purpose of the study, included the satisfaction of the professionals, attitudes toward using the application, and intention or willingness to continue using the application35.

This study was conducted in three phases: Phase (A) Researchers developed an ad hoc questionnaire to explore the use of new technologies. Phase (B) Tests of the usability of the mobile application were performed by the participants while the interaction of the participants with the mobile application was analyzed using the "Think-aloud" approach and facial gesturing, with a categorical approach, based on the six basic facial expressions published by the American Psychological Association (happiness, surprise, fear, disgust, anger, and sadness)36. Phase (C) Using the computer system usability questionnaire (CSUQ)37, user-perceived satisfaction in aspects related to the ease of use, ease of learning, simplicity, effectiveness, information, and user interface of the mobile application were assessed.

Recruitment

Participants were selected through an open call The study was carried out with professionals who were unfamiliar with AppADIm. Candidates from different areas of healthcare and with different years of care experience were included. All of them were identified with an ID to ensure confidentiality. Medical professionals, nurses, and health professionals from different areas of care, such as hospitals, health centers, geriatric residences, home care, and others, were included. All health professionals who had worked with a mobile healthcare data management application comparable to AppADIm were excluded from the study to make the sample more homogeneous in relation to the use of this technology. Thirty-two participants were included in the study and one candidate was excluded38, which is like the number employed in previous studies assessing the acceptance and usability of health apps39,40.

Data Collection in the three phases

Phase A: socio-demographic data and the use of new technologies

Before evaluating the mobile application, the 32 participants completed an online questionnaire, via Google forms, regarding socio-demographic data and entailed general questions as years of experience, training, field of work, personal use of internet and the use of new technologies, developed by the authors based on the recommendations described in the bibliography and validated by a panel of experts.

Phase B: mobile application usability testing

The usability tests of this study were performed at the Center of Simulation and Innovation in Health (CSIS), which is a center dependent on the School of Health Sciences of Tecnocampus, located in the Tecnocampus Science Park. The participants individually performed the usability tests of the mobile application in a room equipped with a filming system. During the tests, the participants completed the tasks that two researchers were presenting from an adjoining room. The tasks evaluated in the usability tests are shown in Table 1. The criteria were tested according to the usability measures proposed in the ISO standard 9241–1141,42. The evaluation followed a specific order to ensure that every user had an individual perspective of each of the tasks to be performed. During the procedure, each participant’s performance was recorded with cameras at different angles, and the researchers observed the reactions and movements from the adjoining room through a double mirror. Simultaneously, mobile phone screens were recorded using an external camera, which provided images or screen recordings (Multimedia appendix 1). Participants were asked to voice any feelings, doubts, or limitations they experienced during the exercise (think-aloud) to supplement the information received. The researchers registered all aspects directly related to the effectiveness and efficiency of the participants and, subsequently, analyzed the interaction of the participants with the mobile application through facial gesturing, with a categorical approach, using the six basic facial expressions.

Table 1 Tasks evaluated in the usability tests.

Phase C: CSUQ

Finally, all participants completed the CSUQ37. This is the Spanish adaptation of the post-study system usability questionnaire43. The CSUQ consists of 16 items rated on a 7-point scale (strongly disagree1 to strongly agree7), and a general satisfaction scale and three subscales: system utility (items 1–6), information quality (items 7–12), and interface quality (items 13–15). Higher scores indicate better usability.

Data analysis

Data analysis was based on audio and video recordings collected by cameras. The voice reactions of the participants in the audio recordings were transcribed verbatim. Incident notes, characterized by comments, silences, or repeated actions, and error messages, were collected through the recordings. The obtained content was analyzed by two members of the research team. Transcripts and critical incidents were also reviewed to identify the most common usability concerns. In any case of discrepancy in content analysis, a third-party reviewer was consulted. The results of the CSUQ questionnaire were analyzed using the statistical program Jamovi. A descriptive, inferential, and univariate study was conducted. In the univariate analysis, the quantitative variables were expressed as centralization and dispersion parameters (mean, standard deviation, etc.), and as qualitative variables, via frequencies and percentages.

Ethical approval

The study was conducted in accordance with the Declaration of Helsinki. The study was approved by the Ethical Committee of the School of Health Sciences of Tecnocampus (CODE: 33/18).

Consent to participate

Participants signed informed consent forms. To ensure confidentiality, only the principal investigator had access to the identity data. The results obtained will be maintained for five years.

Results

Thirty-two participants completed the task scenarios and questionnaire. The main characteristics of the participants are summarized in Table 2. The majority were female and nurses with a high percentage of postgraduate training and the most (68,5%) had at least 10 years of experience. Almost half of participants (46,9%) had the hospital ward as working area and 75% of participants used at least one mobile health application.

Table 2 Characteristics of participants (N = 32).

Table 3 shows the effectiveness of participants that were able to complete the task, the efficiency—i.e., whether end-users can locate the resources using the quickest and most direct route through the application—which is measured by the number of “additional” clicks required for the actions, and the time that participants need to complete the tasks, compared to an expert user.

Table 3 Effectiveness of participants, efficiency of the application and efficiency comparing participant and expert user.

More than 90 per cent of participants were able to complete the task with only some difficult with vital signs (task 5). The number of additional clicks needed was one or less except for the task 5 (vital signs) where participants did more than four. The participants used two times clicks than an expert user.

Various comments were made during the thinking-aloud process. Of the 14 comments recorded, 78.6% (11/14) were related to the task of consulting and recording vital signs (task 5).

Figure 1 shows the interaction of the participants with the application. Most of the surprised reactions were noted during task 5 (consulting and recording vital signs, 50% (16/32)), followed by task 4 (consult and register a clinical note, 31% (10/32)), and task 6 (consult and verify the prescribed medical orders of the patient, 25% (8/32)).

Figure 1
figure 1

Interaction of the participant with the mobile application.

The results from the CSUQ show that the participants were, overall, satisfied with the usability of the application (see Table 4 for details), as can be seen in the general questions section of the questionnaire. Overall, I was satisfied with the mobile application had a score of 6.18/7 (SD: 0.76), and I would recommend the use of the mobile application to other professionals had a score of 6.21/7 (SD: 0.81). Regarding the system quality, information quality, and interface quality, the best-rated category was the quality of the interface, with an average score of 6.04/7 (SD: 0.22), and the lowest rated was the quality of the information, with an average score of 5.35/7 (SD: 0.90).

Table 4 Computer system usability questionnaire (N = 32).

Discussion

The use of UEMs during the development and testing process of health applications is commonly recommended in the literature44,45. Consequently, this study aimed to critically appraise the acceptability and usability of the aforenoted mobile application for health professionals using different available UEMs to detect problems in user–system interactions and to suggest improvements to the application.

Usability tests have shown that the mobile application is efficient (which is measured by the number of “additional” clicks required for the actions and the time that participants need to complete the tasks, compared to an expert user) and effective (which is measured by the percentage of tasks completed). This is because most of the participants did not experience any difficulties performing most of the tasks with the application; moreover, only a few errors were encountered, and the time required to complete a task was comparable to that of an expert participant. This is considered an accomplishment because none of the participants had previously used the application. The most difficult task for the participants was to consult and record vital signs. In addition, most comments during the thinking-aloud process, as well as the tasks wherein the participants interacted significantly with the mobile application through facial gesturing, were also related to consulting and recording vital signs.

Overall, in this study, end-users found the mobile application to be highly usable, as indicated by the survey data (CSUQ), with no major bugs and no issues with the flow of activities. In addition, most participants expressed satisfaction with the mobile application and would recommend the use of the mobile application to other professionals.

These results suggest that the quality of the information provided with the application should be improved, and that the main task to be improved in terms of accessibility and ease of use is the consultation and registration of clinical notes of treatment. Analyzing the results obtained in a broader sense, we observe that the acceptance and satisfaction of the study participants who do not use the mobile application daily is high, like those obtained for professionals who do use it as a professional tool32. This suggests that, in addition to improving specific aspects of the application, a broader analysis should be performed regarding the reasons for the current limited use of the application among all professionals and the preferred use of paper for queries and to record clinical data in a complementary manner. Moreover, in the field of the Hospitalization at Home we need to take in account the aspect of the communication network. Sometimes the use of or non-use of a mobile application are related to weak network services in the area.

Some researchers have posited that one of the reasons that might explain the low usage rates, resistance, rejection of health information technology, and the request for alternative methods is that in the adoption of mobile applications and technologies, functional features and advanced techniques are prioritized, whereas the needs and characteristics of the end-users are neglected46,47. Other studies show that the most influential factor in the use of mobile applications is performance expectancy48, which is understood as the degree to which the user expects that the system will help them attain gains in job performance. Other researchers have stated that the determining factors are the perceived importance of information security, process orientation, documentation intensity, and eHealth-related knowledge49. Therefore, healthcare organizations should, in addition to designing and developing mobile applications that guarantee evidence-based health informatics50 and the utilization of UEMs, also consider performance expectancy as a determining factor in the adoption of new mobile devices; additionally, they should thoroughly analyze the end-users’ needs to identify useful functions for their workflows51.

Limitations

The limitations of the present study include the sample size, although other studies have used similar or lower samples52, and the more presence of the nurse related to the doctor participants. Moreover, the study design did not allow for “learnability” to be measured because of the small sample size and the high efficiency and effectiveness of task scenario completion.

Conclusions

There is clear scientific evidence for the ability of mobile handheld technology to positively impact rapid response, transcription error prevention, information accessibility, and data management in healthcare settings, as well as the beneficial impact of this technology on aspects of healthcare delivery53. This study has shown that the usability of this mobile application, in terms of effectiveness, efficiency, and satisfaction, is significant; however, it is not the only criterion that favors its use in daily practice. Therefore, as other scholars have also noted, further studies are needed to explore the significant antecedents of this mobile application, i.e., system and information quality and the limitations of mobile devices46. Future directions may include improving data integration into the health care system, an interoperable application platform allowing access to electronic health record data, cloud-based personal health records across health care networks, and increasing mobile application prescription by health care providers2.