Digital physiotherapy is a satisfactory and effective method to improve the quality of life in Long COVID patients

Abstract

Objective

This research aimed to explore Long COVID patient's quality of life, satisfaction and perception with an individualized and customizable digital physiotherapy intervention during a 4-week period.

Methods

A pre-post clinical trial was conducted with 32 Long COVID patients. Quality of life was assessed using the 12-Item Short Form Survey and the European Quality of Life-5 Dimensions questionnaire (EuroQol-5D), while satisfaction and perception were measured using the Telemedicine Satisfaction Questionnaire. Optional open-ended questions were added as qualitative approach. A mixed design method was conducted.

Results

After intervention, a statistically significant improvement (p < 0.05) was observed in quality of life. The SF-12 questionnaire showed an increase of 4.04 points in the physical component and 6.55 points in the mental component with a small/medium effect size. The EuroQoL-5D questionnaire demonstrated a medium effect size with an increase of 0.87 points. Patient perception indicated high rates of satisfaction and values above the minimal clinically important difference. The qualitative approach revealed several interesting findings.

Conclusion

Participants found the digital intervention satisfactory and effective in improving their quality of life. Suggestions for improvement, such as the inclusion of face-to-face sessions, a chat for immediate contact, sound in breath exercises in the digital program, longer duration and continuity of intervention, were mentioned. Larger sample studies and in-deep qualitative methodologies are needed to draw extrapolable conclusions.

Trial registration

NCT04742946.

Introduction

The first consensus definition of Long COVID syndrome was presented by the WHO as a condition occurring in people with a history of probable or confirmed SARS-CoV-2 infection, usually 3 months after onset, with symptoms lasting at least 2 months that cannot be justified by an alternative diagnosis. ¹ Research found that only 59% of patients with SARS-CoV-2 infection had positive swabs by reverse transcriptase polymerase chain reaction assays, the standard diagnostic method during the Coronavirus Disease 2019 (COVID-19) pandemic, making clinical presentation decisive. ²

Long COVID syndrome has been recognized as a public health problem; a multi-organ disease, with a wide and heterogeneous range of sequelae on daily functions, job position, health perception and mood among others. ³ The knowledge to date of the underlying ethiology of Long COVID syndrome, as well as its duration and degree of severity, remain limited. ⁴ Research has found that 80% of infected patients persisted for more than 6 months with at least one sequela, showing reduced quality of life, limitations in daily activities and work capacity. ⁵ A national study presented a detailed map with the description of up to 201 symptoms in the Long COVID patient. ⁶ The most prevalent symptoms are fatigue, dyspnoea, myalgia, arthralgia, headache, cough, alteration to smell and taste, brain fog, lack of attention and concentration, as well as there being effects on mental health.^6,7

Clinical practice guidelines emphasize individualized interventions, oriented to symptoms, that improve activities of daily living. ⁸ In the context of Long COVID symptoms, the role of the physiotherapist should include providing information, education, supported self-management, peer support, symptom management strategies and physical rehabilitation. ⁴

Current studies with traditional physiotherapy interventions have shown may be relevant, safe and effective in several outcomes, showing the necessity of rehabilitation intervention for these patients. ⁹ However, a qualitative study determined the hopelessness felt by Long COVID patients in the face of the failure of the different rehabilitation therapies used, ¹⁰ highlighting the need to explore in depth their perceptions and to identify the needs of the patients with the intervention carried out. ¹¹

Digital physiotherapy practice has been seen as a complementary method to provide different rehabilitation services remotely ¹² that can better meet the needs of the patients, especially in terms of ease of access and elimination of travel, proving to be an important component in disease management. ¹³ In addition, the digital physiotherapy practice may offer a new method of care delivery aimed at promoting patient self-efficacy, such as the new standards in healthcare that have been adopted globally, since the COVID-19 pandemic. ¹⁴

Published data in several pathologies have shown the importance of assessing the quality of life and the satisfaction and perception with digital interventions. ¹⁵ Studies with digital interventions have shown improvements in dyspnoea, and physical function,^16,17 underlining the need to investigate the effects on quality of life, ¹⁸ patients’ perception and satisfaction with different intervention models ¹ in Long COVID patients.

In digital interventions, questionnaires and surveys are often used to measure users’ experiences related to technical quality, perceived usefulness and interaction with the system. ¹⁶ Healthcare professionals need to be aware of and evaluate patients' experiences in order to provide truly patient-centred care. ¹⁹ However, a broader perspective is needed to explore the biopsychosocial complex of patients and healthcare delivery. ²⁰ Recent research indicates the need for more studies to be designed to investigate factors that may influence patient satisfaction with the interventions provided. ²¹

Qualitative methods are used to explore a deeper contextual understanding of participants’ experiences with interventions, ²² including digital physiotherapy practice. ²³ In addition, mixed methods research, combining qualitative and quantitative methods, is an important methodology to investigate complex health-related topics. ²⁴

Therefore, digital physiotherapy is presented as an opportunity in the current healthcare framework that can provide solutions to the Health Systems. Thus, research exploring the effects on quality of life and patients’ perceptions in Long COVID patients is highly justified.

Objectives:

• - To assess the effectiveness and the magnitude of the effect of a digital physiotherapy intervention on quality of live outcomes in patients diagnosed with Long COVID syndrome.

• - To explore satisfaction and perception with a customizable 4-week digital physiotherapy intervention. A mixed method.

Materials and methods

Study design

This study was carried out in accordance with Good Reporting of a Mixed Methods Study. ²⁵ In addition, a mixed quantitative–qualitative study was designed based on the consolidated standards of reporting trials criteria ²⁶ and The Standards for Reporting Qualitative Research. ²⁷ This study is embedded in larger research that also explored the functional capacity and adherence of a digital physiotherapy intervention in Long COVID patients. ¹⁷ The research team found it appropriate to use a qualitative constructionist framework in a study that sought to describe the views and experiences of a health intervention. A triangulation method was added to reveal findings that need further interpretation. ²⁸ A mixed methods design was used, including patient-reported outcome measures via open-ended questions. The study started with a pre-post digital physiotherapy intervention (quantitative phase) and ended with a self-report questionnaire (quantitative–qualitative phase). The qualitative data were analysed using a thematic analysis approach.

The sample size (n = 27) was calculated using an online calculator ²⁹ where we assumed a mean effect size of 0.5, a significance level of 0.05 and a power of 0.8 for a single-tailed test.

Patients

The study includes adults with a diagnosis of Long COVID syndrome, ICD-10 (U09) e ICD-11 (RA02), ³⁰ according to the clinical history provided by their health centre, the initial assessment made by the principal investigator, and following the WHO recommendation, such as described in the introduction section.

Patients were recruited through non-probabilistic sampling due to the characteristics of the subjects and for the convenience of the study from various health centres in Andalusia during 2022. The collaborators (physiotherapists, nurses and family doctors from the reference centres) were informed about the characteristics of the study in personal interviews and project presentations.

Inclusion criteria: Adults over 18 years of age, with diagnosis of Long COVID syndrome. ³¹ Participants had to reside in Andalusia during the research period, have computer technology with internet connection at home (tablet, laptop, personal computer, or smartphone), and be able to access email.

Exclusion Criteria: Inability to use technological tools and/or present comorbidities that prevent the completion of the digital physiotherapy program. ³²

Intervention

Participants received a 4-week personalized digital physiotherapy program based on the initial assessment by an evaluator from the physiotherapy department of the referral centre. The program is sent by email and allows for continuous monitoring of patients. The prescribed exercises, the number of repetitions and sets, as well as the progression criteria, can be customized and are based on published clinical guidelines. Digital physiotherapy interventions included personalized recommendations for each patient, starting at low intensity and duration and gradually increasing; a session duration of 20–30 min, with 3–5 sessions per week, is recommended, although it will always depend on the patient's feeling of fatigue and/or dyspnoea. ³³ The number of synchronous sessions (1 to 1) via video call and WhatsApp messages was determined by the initial evaluation. An example of programme is shown in Figure 1.

Figure 1.

Example of programme.

Outcome measures

Sociodemographic variables, affiliation data, age, sex, and location were collected in an initial interview.

• - Quality of life:

The 12-Item Short Form Survey (SF-12) and The European Quality of Life-5 Dimensions (EuroQoL-5D) questionnaires were used for the assessment of health-related quality of life.

• The 12-Item Short Form Survey questionnaire (SF-12).

The SF-12 questionnaire version 1.0 was used; the questionnaire shows good correlation and has been considered an adequate instrument to measure the general health status of the population with high internal consistency 0.83–0.90. ³⁴ The SF-12 questionnaire assesses eight dimensions of health-related quality of life including physical function, physical role, body pain, general health, vitality, social function, emotional role and mental health, and two summary scores are reported: a physical component score (PCS-12) and a mental component score (MCS-12). ³⁵ The population average PCS-12 and MCS-12 are both 50 points. The population standard deviation is 10 points. So, each 10 increments of 10 points above or below 50 correspond to one standard deviation away from the average. The SF-12 higher scores are indicative of better quality of life. ³⁶ A SF-12 questionnaire is shown in Supplemental material.

• The European Quality of Life-5 Dimensions questionnaire (EuroQoL-5D).

The EuroQol-5D questionnaire includes five dimensions (mobility, self-care, activities of daily living, pain and anxiety/depression). In each dimension of the EuroQol-5D, severity levels are coded 1 if the response option is ‘no (I have) problems’; 2 if the response option is ‘some or moderate problems’; and 3 if the response option is ‘many problems’. EuroQol-5D score ranges from 5 to 15. In this case, the EuroQol-5D higher scores are indicative of worse quality of life. ³⁷ Cronbach's alpha values of each dimension ranged from 0.63 to 0.77. ³⁸ The EuroQol-5D questionnaire is ‘generic’ because it measures health in a way that can be compared across different sorts of patients, disease areas and treatments. ³⁹ Research confirms that the EuroQol-5D questionnaire has good psychometric properties to assess quality of live in long COVID patients. ³⁸ A EuroQol-5D questionnaire is shown in Supplemental material.

• - Satisfaction and perception:

To explore patient satisfaction and perception, we use the Telemedicine Satisfaction Questionnaire (TSQ) as a quantitative approach, ⁴⁰ and open-ended questions as a qualitative method.

• The Telemedicine Satisfaction Questionnaire (TSQ).

The TSQ questionnaire explores patient satisfaction, including aspects such as quality of care, interpersonal interactions and technical quality of virtual connections in three subdomains (TSQ1 : quality of care provided, TSQ2: similarity to face-to-face encounters and TSQ3: perception of the interaction). ⁴¹ It presents an internal consistency of 0.93, indicating strong correlations between items and is considered acceptable. ⁴² The questionnaire items were scored on a 5-point Likert scale, from 1, strongly disagree, to 5, strongly agree. ⁴⁰ TSQ score ranges from 14 to 70, based on previous reports. A TSQ questionnaire is shown in Supplemental material.

• Open-ended questions

To explore the perception of the participants, we used 4 open-ended questions as a qualitative approach. ⁴³ The open-ended questions or free questions should provide more details than questionaries. ⁴⁴ The open-ended questions were added to the TSQ questionnaire. Participants were queried on their intervention experiences and perceptions as result of receiving digital physiotherapy practice. The questions were as follows:

• - How would you improve the digital physiotherapy intervention service you have received for 4 weeks?

• - What has been your experience with the use of digital physiotherapy intervention for 4 weeks?

• - What would you remove from the digital physiotherapy intervention?

• - What would you add to the digital physiotherapy intervention?

Data collection procedure and statistical analysis

Once the study subjects were informed, data were collected by an evaluator in the physiotherapy department for statistical analysis. A flow diagram of the study shows procedures for recording, including T.0 (Pre) at baseline and T.1 (Post) at the end of the intervention. The flow diagram is shown in Figure 2.

Figure 2.

Flow diagram study design.

Information was added to the database created for this purpose using exportable data tables for statistical analysis. A study participation number was assigned to each of the participants (ID-01, ID-02…). Data anonymization was performed by the principal researcher. Statistical analysis was performed by a descriptive analysis of the quantitative data (SF-12, EQ-5D), using a paired Student's t-test to compare differences pre-post intervention outcomes. A descriptive analysis of the TSQ questionnaire (satisfaction/perception) was performed, and the effect size was analysed using Cohen's d, ⁴⁵ which classifies effect size as small (0.2–0.5), moderate (0.5–0.8), or large (>0.8).

Two researchers (P. P.-E. and M.-J. V.-G.) had no prior knowledge of the intervention performed, independently read all open-ended responses line by line and applied a thematic content analysis to gain an in-depth understanding experienced by participants during the digital physiotherapy practice intervention. The qualitative data generated through the open-ended questions were content analysed and categorized into themes. The relevant characteristics were coded taking into account the research question. ⁴⁶ Finally, the themes were named with the all members of the research team consensus. Responses were sent to each participant who then had the opportunity to give their feedback. All data are available at principal investigatoŕs request.

A measure that helps to quantify and understand the results achieved is the minimal clinically important difference (MCID), which complements significance. The MCID is defined as the smallest difference in score in any domain or outcome of interest that patients are able to perceive as beneficial or harmful. ⁴⁷ The MCID was assessed in this research. A 95% of confidence level and a p-value of less than p < 0.05 were considered statistically significant in all statistical analysis. SPSS software v22 was used.

Results

A total of 32 participants completed the 4-week intervention and were included in the analysis. The majority of participants were female (71.9%). A very small percentage were in the intensive care unit (6.3%), of the few who required hospitalization (9.4%). Age (range 18 to 65 years) and symptomatology (fatigue, joint pain, shortness of breath, memory loss, headaches) were heterogeneous among participants at baseline. Participant characteristics are shown in Table 1.

Table 1.

Participants characteristics. M:Media SD: Standard deviation.

	Participants (n = 32)
AGE (M/SD)	45.938 ± 10.65
Gender woman % (n)	71.9% (23)
Hospitalized % (n)	9.4% (3)
ICU % (n)	6.3% (2)

Quantitative results

The average score of the physical component (PCS-12) in the SF-12 was 26.42 (SD 9.65) and the average score of the mental component (MCS-12) was 43.52 (SD 11.23). The average score in the EuroQol- 5D was 9.1 (SD 1.53). After the intervention, the results showed a statistically significant improvement (p < 0.05) in quality of life. The results confirm a small effect size for the SF-12 in the physical component (PCS-12) with an increase of 4.04 points, and an increase of 6.55 points for the SF-12 in the mental component (MCS-12) with a medium effect size. Additionally, the EuroQoL-5D questionnaire showed a medium effect size with an increase of 0.87 points. Table 2 summarizes the results of the SF-12 and EuroQol-5D questionnaires.

Table 2.

Quality of live results.

	Inicial (M/SD)	Final (M /SD)	Correlation	Sig.	Coheńs d	Effect size	Effect size
PCS-12	26.42/9.65	30.46/10.08	.80	.001	.41	.20	Small
MCS-12	43.52/11.23	50.07/10.19	.54	.001	.61	.29	Medium
EuroQoL-5D	9.18/1.53	8.31/1.57	.68	.000	.56	.27	Medium
PCS-12: physical component score in SF-12 questionnaire: MCS-12: mental component score in SF-12 questionnaire; EuroQoL-5D: The European Quality of Life-5 Dimensions questionnaire; M:Media; SD: Standard deviation; Correlation: Correlation; Sig: Bilateral signification

At the end of the intervention, the 32 participants completed the TSQ questionnaire. The results confirm that participants in this study were highly satisfied with the digital physiotherapy practice. A TSQ total score >56 has been considered a good experience in previous research. ⁴⁸ The total mean score of the TSQ questionnaire in this study was 65.25 ± 6.02, with a maximum of 70 points.

The mean scores for the TSQ questionnaire for all participants ranged from 3.84 to 4.93 on a Likert Scale (0–5). The highest scores were in domains TSQ2: similarity to face-to-face encounters and TSQ3: perception of the interaction with 4.93 ± 0.24 points. The results showed the participants rated accessibility, ease of use and comfort with the type of tool used in the intervention very favourably, mainly with the care received from the physiotherapist. In contrast, the lowest scores were in domain TSQ1: quality of care provided with 3.84 ± 1.16 points corresponding to item 5.- ‘I do not need assistance while using the system’, and with scores 4.43 ± 0.84, 0.75 points respectively corresponding to items: 8.- ‘I obtain better access to health care services by use of telemedicine’ and 10.- ‘I find Telemedicine an acceptable way to receive health care services’. The results revealed possible difficulties or barriers in the development of the intervention. Table 3 summarizes the TSQ results.

Table 3.

Telemedicine satisfaction questionnaire results.

TSQ questionnaire	Minimum	Maximum	Media	Standard deviation
Total	47.0	70.0	65.25	6.02
1. I can easily talk to my healthcare provider.	4.0	5.0	4.93	0.24
2. I can hear my healthcare provide clearly	4.0	5.0	4.93	0.24
3. My healthcare provider is able to understand my healthcare condition	4.0	5.0	4.93	0.24
4.I can see my healthcare provider as if we met in person	3.0	5.0	4.71	0.52
5. I do not assistance while using the system	2.0	5.0	3.84	1.16
6. I feel comfortable communicating with my healthcare provider	4.0	5.0	4.93	0.24
7. I think the healthcare provided via telemedicine is consistent	3.0	5.0	4.81	0.47
8. I obtain better access to healthcare services by use of telemedicine	2.0	5.0	4.43	0.84
9. Telemedicine saves me time travelling to hospital or a specialist clinic	3.0	5.0	4.78	0.55
10. I do receive adequate attention	4.0	5.0	4.93	0.24
11. Telemedicine provides for my healthcare need	2.0	5.0	4.46	0.80
12. I find Telemedicine an acceptable way to receive healthcare services	2.0	5.0	4.43	0.75
13. I will use Telemedicine services again	3.0	5.0	4.62	0.60
14. Overall, I am satisfied with the quality of service being provided via telemedicine	3.0	5.0	4.84	0.44

Qualitative results

All participants answered the four open-ended questions included in the TSQ questionnaire.

With regard to the question ‘How would you improve the digital physiotherapy intervention service you have received for 4 weeks?’, 15 subjects informed that this type of the intervention was adequate and positive.

• - Nothing would improve (ID 003)

• - Effective, convenient, simple (ID 012)

• - Service is very adequate (ID 016)

While of the remaining 17 participants, n = 5 would improve the application with respect to the timer or lack of audios; n = 6 demanded more online (n = 4) or face-to-face sessions (n = 2); and the rest (n = 6) suggested increasing the time of the intervention carried out.

• - Supporting videos should have sound and guidance through spoken instructions as well as guidelines and timing (ID 011)

• - with more online or face-to-face session (ID 021)

• - Extending service time (ID 002)

With regard to the question ‘What has been your experience with the use of digital physiotherapy intervention for 4 weeks?’, all participants noted that the intervention has been positive, using different articles as unbeatable, excellent or highly beneficial, among others.

With regard to the question ‘What would you remove from the digital physiotherapy intervention?’, the majority of participants indicated that they would not remove anything from the intervention, with the exception of n = 3 who would remove the application errors they encountered during the exercises, such as chronometer failures or lack of sound.

• - Some bugs in the app (ID 011)

And finally, regarding the question ‘What would you add to the digital physiotherapy intervention?’, of the 32 participants, n = 10 indicated being able to increase the time of the intervention carried out (they even reported the intention to continue self-managing the application), n = 8 would combine face-to-face sessions with the digital practice of physiotherapy and n = 3 suggested the possibility of including in the application a chat for doubts and comments with the physiotherapist. The rest of the participants (n = 11) stated that they were very happy with the intervention carried out and did not believe that any changes were necessary. It was suggested to extend the intervention to other study populations (such as patients starting chemotherapy) or that intervention be facilitated by the public health system.

• - More time, if possible. It has helped me to start the change and to have an improvement that I still have a long way to go (ID 031)

• - If possible, a face-to-face session (ID 001)

• - More sessions in order to resolve doubts (ID 021)

• - In the exercise program, I would add a section for observations so that annotations can be made (ID 014)

Two core themes emerged from the thematic analysis concerning the outcomes perceived by participants after the digital physiotherapy intervention. The themes were labelled as ‘Benefit and Progression of Exercises Helpful’ and ‘Ease and Issues with Home use of Technology’.

All participants found the use of the personalized digital physiotherapy program helpful. Participants reported that the progression of the program during the 4-week intervention was especially meaningful and facilitated them to achieve the reported gains. However, participants suggested improvements in the digital physiotherapy practice with the intention of facilitating access and maximizing potential outcomes.

Discussion

This mixed methods study increases the knowledge available on the quality of life, satisfaction and perception of Long COVID patients with a digital physiotherapy practice intervention, addressing the main objective of the research.

Positive findings have been published in quantitative or qualitative method studies, using digital physiotherapy applications in different populations to control symptoms and reintegrate into daily life. ⁴⁹ To our knowledge, this is the first mixed methods study describing the perceptions of Long COVID patients enrolled in a digital physiotherapy program.

Quantitative results showed significant changes in perceived quality of life and optimal satisfaction values. Participants also highlighted a qualitative set of outcomes as ‘Benefit and Progression of Exercises Helpful’ and ‘Ease and Issues with Home use of Technology’.

A recent research evaluating 143 patients indicates persistence of symptoms and a reduced quality of life. ⁵⁰ The 32 participants included in this study maintained a variety of symptomatology ranging from one and a half years to 6 months, with a diminished quality of life (SF-12 = (PCS-12) 26.42 / (MCS-12) 43.52 and EuroQol- 5D = 9.1). The participants had not received ongoing physiotherapeutic treatment prior to the start of this research, although they received education programs about their symptoms and health, reporting feeling neglected in their recovery process.

Our results showed statistically significant (p < 0.05) improvement in quality of live with small to medium effect size, and values above MCID. A review of 11 studies across a variety of health conditions found that effect size for SF-12 questionnaire ranged from 0.12–0.87, with a mean of 0.39, and were in the ‘small to moderate’ using Coheńs criteria. ⁵¹ Studies previous show the MCID of the SF-12 questionnaire can be considered clinically relevant with improvements >3.77 in MCS-12 and >3.29 in PCS-12. ⁵² In our study, small and medium effect size was shown and an increment of +4.04 points for PCS-12 and of +6.55 points for MCS-12 with the SF-12 questionnaire was achieved. The results obtained after the digital physiotherapy intervention represent a significant improvement in only 4 weeks. Our study coincides with the results obtained in a research on similar subjects with unsupervised digital intervention in 6 weeks. ⁵³

A study exploring the responsiveness of the EuroQol-5D questionnaire in a healthcare group in Australia found changes of small magnitude, with an effect size of 0.1. ⁵⁴ A previous study found that a change of at least 0.26 for the EuroQol-5D questionnaire index represented MCID in patients with Long COVID syndrome. ⁵⁵ In this research, an improvement of 0.87 points was obtained with an effect size (medium) of 0.56.

Overall, only a 4-week digital physiotherapy program was effective in improving the quality of life of our participants, with an intervention of digital physiotherapy practice.

The results of reviews indicated that digital physiotherapy intervention may be an effective strategy to improve quality of life and reduce dyspnoea, ⁵⁶ functional capacity, ⁵⁷ and has been found at least non-inferior to usual care. ⁵⁸ However, caution should be exercised to avoid overestimating the results, ¹⁴ due to possible methodological shortcomings.

In addition, a high level of satisfaction was observed with the TSQ questionnaire; therefore, our results are consistent with previous research with digital physiotherapy interventions in non-Long COVID patients, adding further knowledge and data to the topic of study. ⁵⁹ The lowest score achieved in TSQ was 3.84 points with the item 5: ‘I do not need assistance during the use of the system’. This result can be interpreted as the need for improvements in the use of digital physiotherapy practice, with which to work towards a better health service.

Patient feedback and end-user perspectives provide important information regarding this new delivery intervention model, which may have a substantial impact on future uptake. ⁶⁰ In addition, qualitative methods are well suited to generate rich data about phenomena in their context and can help develop hypotheses for further research, as well as inform the development of patient-centred interventions. ⁶¹

In our research, possible improvements were indicated during the use of the technology at home. A minority number of participants expressed difficulties with the timer and some doubts in the performance of certain exercises. The introduction of a chat for queries or the inclusion of sound in the videos could clarify existing questions at that moment. All the barriers or difficulties were resolved in the video calls or WhatsApp messages.

While digital physiotherapy practice have delivered great benefit to patients by lowering barriers to accessing care, ⁶² the above-mentioned needs must be addressed in order to support their implementation.

Research has shown that patient satisfaction with an intervention is influenced by the results obtained, the patient–provider interaction, ²¹ and in the case of a digital intervention by the quality of the technology used. ⁶³ Furthermore, the ability of professionals to adapt to new technologies and adopt them in their practice must be considered. More research addressing digital health training for both providers and patients is needed for better implementation. ⁶⁴

In this research, the qualitative phase showed that all participants found the use of the program useful thanks to its benefits and progression. A critical point of our study was exercise planning and its adaptability to patients, according to perceived effort and to their symptomatology. Individualization was crucial for the implementation of this digital physiotherapy intervention, as has been previously argued. ⁶⁵

Summarized, the results of qualitative approach indicate that the digital physiotherapy program can be individually prescribed, remotely monitored and adjusted. The themes obtained are consistent with previous studies, suggesting that the proposed quality principles for an expanded COVID service should ensure access to care. ⁶⁶

The quantitative results show that participants received adequate care, although they requested a longer duration and continuity of intervention, as well as a greater number of sessions, as indicated by the qualitative results.

Based on the results obtained in our study, the digital physiotherapy intervention may provide participants with the knowledge and self-efficacy to continue exercising and managing ongoing symptoms beyond the 4-week time-limited intervention. In this way, the initial intervention could be used to assist individuals in the continued management of their health.

According to the suggestions obtained, the future with Digital Physiotherapy Practice may involve extending it to other areas or even incorporating it into health services.

Limitations and strengths of the study

This study has one main limitation, in common with most qualitative studies, it is small in scale and thus does not claim to be generalizable; rather, the study provides insights into the views and experiences of the participants. ²² Regarding of strengths, the researchers who carried out the content analysis of the open-ended questions had no prior knowledge of the intervention performed, avoiding possible biases.

As patients use their own technological devices, the rapid implementation process was guaranteed. However, patients without access to the technology may find it difficult to participate in this intervention, which may lead to selection bias. Other limitations are related to the use and technological difficulties (disconnection, device failures) that may arise during the course of the intervention and that must be considered. The short duration of the intervention, only 4 weeks, is another limitation to consider, although recent publications have shown improvements with interventions of only 7 days.^67,68

The small sample size (n = 32) can be considered as another limitation however, previous research has reported reliable and valid results even in the absence of a large sample size. The goal of rehabilitation research should not be to abolish small sample size studies, but rather to support transparency and encourage replication. ⁶⁹

And finally, the greatest disadvantage of quasi-experimental studies is that randomization is not used, limiting the study's ability to conclude a causal association between an intervention and an outcome. ⁷⁰ Nevertheless, quasi-experimental studies are often used to assess rapid responses to outbreaks and are pragmatic within their inherent design limitations. ⁷⁰ At the Harvard Public Health conference in 2017, the need to generate and disseminate greater knowledge of quasi-experimental studies ⁷¹ to demonstrate the impact of external validity on clinical practice and community effectiveness was highlighted, ⁷² which would allow them to be adequately evaluated for inclusion in systematic reviews.

In the absence of major difficulties during the course of the intervention, and with patients reporting no adverse effects during the intervention, we regard our intervention to be feasible, safe and consistent with our objectives. Most patients in the sample found digital physiotherapy practice valuable, appreciating the individual nature of the approach.

The digital physiotherapy practice could provide an effective response to the health problems ⁷³ as the results of this study have shown. The results of this study have been shown to be consistent with the efficacy of digital physiotherapy interventions in several conditions^74–77 and increase the scientific knowledge about their use.

Conclusions

After the 4-week digital physiotherapy practice intervention, a statistically significant improvement (p < 0.05) was observed in the quality of life, with small and medium effect sizes, high rates of satisfaction and values over MCID, in patients diagnosed with Long COVID syndrome.

The use of digital physiotherapy practice was highly rated by the participants, although some improvements were suggested, such as the need to include face-to-face sessions in the intervention. The qualitative approach has revealed items of interest in understanding the perception of the Long COVID patients. The triangulation method allows us to increase the available knowledge on the use of digital physiotherapy practice in patients with Long COVID syndrome. The results obtained on quality of life, satisfaction and perception are in accordance with those previously obtained on functional capacity and therapeutic adherence, which encourages researchers to continue exploring this topic in future lines of research. However, further randomized clinical trials, studies with larger samples, and in-deep qualitative methodologies are needed to draw extrapolable conclusions.

Appendix

Abbreviations

COVID-19

Coronavirus Disease 2019

WHO

World Health Organization

CONSORT

Consolidated Standards of Reporting Trials

SRQR

Standards for Reporting Qualitative Research

COREQ

Consolidated Criteria for Reporting Qualitative

SF-12

12-Item Short Form Survey questionnaire

EuroQol 5-D

European Quality of Life-5 Dimensions questionnaire

TSQ

Telemedicine Satisfaction Questionnaire

COPD

Chronic Obstructive Pulmonary Disease

MCID

Minimal Clinically Important Difference

MCS-12

Mental component store in SF-12 questionnaire

PCS-12

Physical component store in SF-12 questionnaire

ID

Identification

M

Media

SD

Standard deviation

Sig

Bilateral signification