Introduction

Use of mobile applications (or apps) in healthcare has experienced an exponential increase in recent years, with over 350,000 apps being available at the present time¹. Many of these apps have numerous advantages for improve patient care. They also enable healthcare providers to access clinical information in real time and they provide patients with the possibility to remotely manage their disease, allowing them to play a more active role in looking after their health^2,3.

The apps' most popular features include being able to access health information and resources, communicating with healthcare providers, controlling symptoms and keeping track of patient adherence to their medication, among other clinical data^4,5. The term patient-reported outcomes (PROs) refers to health outcomes such as quality of life, functional status, health status, satisfaction, etc. that are reported by patients without being interpreted by a healthcare provider^6-8. Thus, PROs allow patients to provide subjective information about their disease or their treatment, taking on a more proactive role and contributing to the promotion of patient-centered medicine⁶.

Use of apps may increase the efficiency of the process involved in recording and monitoring PROs by bringing down hurdles such as consumption of resources, lack of time and the difficulty to implement a real-time continuous registry^9-11. For that reason, the recording of data is one of the features of these apps that contributes the highest added value in following up on chronic patients^5,12. These data, which may be recorded automatically or introduced by the patients themselves, may be transformed into valuable information for clinicians, who may use them as valuable decision-making tools, improving the quality of care afforded to patients without the latter having to travel to their health center. Chronic conditions such as diabetes, Parkinson's disease, cardiovascular disease and cancer, which require continuous monitoring by healthcare providers, can especially benefit from this kinds of tools^11,13,14.

Apps have shown that they can lead to improved health outcomes in patients with the above mentioned conditions. Such improvements may range from greater satisfaction levels to a decrease in the number of complications or even fewer hospital admissions. A case in point is that of the e-Oncosalud app, aimed at patients on treatment with oral antineoplastics, which has been shown to reduce drug-related problems (DRPs), increase adherence to treatment, enhance health-related quality of life and reduce the consumption of resources in these patients¹⁵. Nonetheless, the apps that allow recording and monitoring of PROs are in the minority, which means that there is Little evidence on the ability of patient-targeted apps to improve their health outcomes^4,5,13,16.

The purpose of this study was to carry out a review of the available evidence on the role of mobile apps in PRO registration and on the impact that using such apps may have on health outcomes.

Methods

A literature search was conducted for studies on apps aimed at recording PROs, which also analyzed the impact of the app itself on patient-related outcomes.

The search was carried out in the course of April 2021 in Medline (through Pubmed) and Embase. The search terms used were “app”, “mobile applications”, “patient reported outcomes”, “outcome assessment, health care” and “quality of Life.” The search was performed for all fields, adapting each of them to the standard database search systems. No date restrictions were applied to maximize the number of publications identified.

To be included, articles had to be published in English or in Spanish, with no time restrictions, and had to dwell on apps used by patients, family members and/or caregivers that measured some kind of PRO, such as adherence, quality of life or other health endpoints. Articles analyzing telemedicine-based interventions other than apps were excluded, as were systematic reviews, editorials, PhD dissertations and opinion pieces.

An analysis was made of the titles and abstracts of the articles obtained. Articles that met the selection criteria were downloaded and subjected to a full-text review. A second author reviewed the articles where doubts arose regarding the selection process. The variables analyzed in each article were as follows: author(s) of the article, publication year, studied population, sample size, health outcomes measured, health outcomes obtained, and whether a pharmacist participated in the study.

Results

The literature review yielded a total of 454 references. Once duplicates were removed, a total of 370 were excluded for not meeting the established inclusion criteria. At the end of the selection process, the 58 remaining articles that met the inclusion were subjected to a full text review. Finally, 26 of the review articles were included. Figure 1 provides a detail of the selection process.

Figure 1.  Article selection process 

Of the 26 articles reviewed, 19 (73.1%) were clinical trials, 4 (15.4%) were quasi-experimental studies, and 3 (11.5%) were observational studies. Two of the clinical trials were pilot studies. The selected articles were all published between 2017 and 2021, with 50% of them corresponding to 2020. A pharmacy department was involved in 4 studies (15.4%) and 3 of the studies (11.5%) has been carried out in Spain. Table 1 summarizes the characteristics of the studies analyzed^17-40.

Table 1.  Summary of the characteristics of the studies analyzed 

Table 1 (cont.).  Summary of the characteristics of the studies analyzed 

Table 1 (cont.).  Summary of the characteristics of the studies analyzed 

ACTS: Anti-Clot Treatment Scale; DASS-21: Depression Anxiety Stress Scale-21; DBP: diastolic blood pressure; EHFScBS: European Heart Failure Self-care Behaviour Scale; EORTC QLQ: European Organization for Research and Treatment quality of life tool; EQ-5D: European Quality of Life-5 Dimensions; FACIT-TS-PS: Treatment–Treatment Satisfaction– Patient Satisfaction; FACT-G: Functional Assessment of Cancer Therapy–General; GAD-7: Generalized Anxiety Disorder 7-item Scale; CG: control group; EG: experimental group; ICIQ-UI SF: International consultation on incontinence questionnaire – Urinary incontinence short form; KCCQ: Kansas City Cardiomyopathy Questionnaire; KDQOL-SF: Kidney Disease Quality of Life survey; MDASI: MD Anderson Symptom Inventory; MMAS: Morisky Medication Adherence Scale; PHQ-9: 9-Item Patient Health Questionnaire; SBP: systolic blood pressure; SEMSA: Self Efficacy in Sleep Apnea; SMAQ: Simplified Medication Adherence Questionnaire.

The sample size of the studies ranged between 14 and 411 subjects. As regards the types of patients analyzed, most of the articles included cancer patients (11 [42.3%] studies) and patients with cardiovascular conditions [7 (26.9%) studies].

Most studies focused on measuring the impact of the apps analyzed on quality of life (50%), control of clinical parameters (46.2%), adherence (38.5%) and management of symptoms and reduction of complications (26.9%). The remaining studies analyzed the impact of the studied apps on the consumption of resources and on the patients' satisfaction with the level of care received.

Overall efficacy in terms of the percentage of patients where a significant improvement was observed following the use of an app was 73.1%. In spite of that, results were rather heterogeneous across the different interventions analyzed. The PROs where the use of an app was found to have the greatest impact were adherence, health-related quality of life and satisfaction.

Discussion

This is the first review published to date dedicated to evaluating whether apps that collect PROs are able to improve patients' health outcomes. Oncology is the area that has seen the greatest development of health apps. A total of 42.3% of the articles analyzed investigated the impact of apps on the health of cancer patients, as compared with 26.9% for cardiology patients and 7.7% for surgical or psychiatric patients among others.

A total of 73.1% of the studies reviewed reported that the use of apps resulted in a statistically significant improvement in the evaluated health outcomes. In spite of the limited sample size in some studies, the fact that the majority were randomized clinical trials endows them with a measure of robustness. The most promising findings in the present review were the improvements in health-related quality of life, satisfaction with the care received and adherence to treatment, which was the PRO where apps had the most positive impact.

The review showed that up to 70% of the studies analyzing the potential of apps to improve adherence show a positive effect, adherence rates reaching 100% in some patients^{15,19-21,23,25,40}. Eight of these articles were clinical trials and two quasi-experimental studies. All of them but one measured other PROs apart from adherence, with Gomis-Pastor et al. being the only study whose main goal was to improve adherence through the use of an app. The authors concluded that an app-based strategy can significantly improve adherence as well as the patients' beliefs regarding their medication⁴⁰. The improved adherence observed in cardiology patients was shown to reduce the number symptoms not only in those patients but also in others²³. In fact, 42.9% of studies analyzing the impact of apps on symptom control showed a statistically significant improvement, with similar results across the different studies in terms of symptom management^18,20,25. This could mean that apps that collect PROs may play an important role in patient safety, ensuring continuity of care and promoting proper PRO management. According to a clinical trial on patients with breast cancer, which analyzed the impact of an app on the reduction of adverse events and on the improvement of the patients' psychological status, the use of a health app was associated with a lower number of adverse events such as nausea, fatigue, hand foot syndrome and hair loss. Although no statistically significant differences were found in most cases, the incidence of grade 3 fatigue was significantly lower in patients who used the app²⁰.

The collection of PROs and an appropriate management of toxicity have not only been shown to improve patient safety but also to impact their quality of life. For example, Grašič Kuhar et al. observed that use of an app by patients with breast cancer helped them better cope with their symptoms, which resulted in an increased quality of life²⁹. This review showed that quality of life was the most frequently investigated variable, accounting for 50% of all analyzed PROs. This shows the importance given in the literature to quality of life, whose measurement is a way of evaluating the population's health and of analyzing different healthcare interventions^41,42. A total of 61.5% of studies showed that quality of life is normally significantly impacted by the use of the app, regardless of the instrument used to measure it^{15,18,19,25,26,29,35,37}. However, Greer et al., which analyzed a sizable patient sample, failed to detect statistically significant differences with respect to the control group. These authors concluded that, although the app could possibly improve health outcomes for all the patients who were prescribed oral antineoplastics, it may be that the intervention is only beneficial for patients with certain risk factors, such as difficulties with adherence or anxiety²⁷. Of the three studies that were only aimed at improving quality of life, Graetz et al. did not report any improvements in the experimental group. It must be noted, nevertheless, that this was a 29-patient strong pilot study²³. The other two studies, one of them observational (Lozano-Lozano)²⁶ and the other quasi-experimental (Li et al.)³⁷, did show statistically significant quality of life differences in favor of the app analyzed.

With respect to resource consumption, the majority of studies focused on analyzing the impact of this variable on cancer and surgical patients, half of them showing statistically significant differences in favor of the app analyzed^17,28,32. Most of these studies were on surgical patients and showed that follow-up based on an app may reduce the number of hospital visits and the patients' need of nursing care after surgery. It must be noted, however, that none of these studies was designed to analyze the impact of apps on patients' care needs or on the level of patient/healthcare provider communication. Further studies are needed to shed more light on these issues.

Finally, four studies recruited the active participation of a pharmacist in the implementation of the apps and the follow-up of the patients^15,25,34,40. All of them revealed statistically significant differences in favor of the apps analyzed. Although the number of pharmacists involved was low, the fact that they were recruited at all is indicative of the important role that pharmacists may play in these technologies. As healthcare providers accustomed to using and validating the new technologies applied to drug administration and patient safety, pharmacists should be regarded as key players in the development of technological initiatives aimed at humanizing care and ensuring the appropriate use of medication.

One of the limitations of this study was the fact that the title- and abstract-based selection of articles was made by a single author. However, to reduce the possibility of bias, a second author was asked to conduct a full text review in cases any doubt emerged in connection with the articles. Furthermore, the possibility exists that an important study for the analysis may have been left out. It must be said, however, that a specific search strategy was designed to identify as many articles as possible.

There is emerging evidence that apps have a positive impact on patients' health outcomes. Use of these tools is making it possible to enhance the management of certain conditions and to achieve outcomes associated with fewer complications, less consumption of resources, improved adherence and better quality of life. These findings should prompt the development of a new self-management model able to promote a healthier lifestyle among patients. Further research is required to determine the applications and limitations of these findings and evaluate the factors that may contribute to improving the outcomes obtained.