1. Introduction
troke is one of the leading causes of long-term disability in adults. Stroke damages the sensory, motor, perceptual, visual, and cognitive systems, impairing the patient’s ability to perform daily activities of life. About 30%-40% of people who survive a stroke have severe disabilities that reduce their functional abilities, including the ability to walk. Given that impaired balance and walking and a high risk of falling at all stages after a stroke have been reported as a major problem in stroke patients, improving balance and gait with proper speed and safety is the main goal in rehabilitation of people with stroke. One of the new methods of treating stroke patients is mirror therapy. This method focuses on the movements of the limbs with no injury; during the mirror therapy, the person pays attention to the movements of healthy limbs in the mirror and receives visual feedback. Mirror therapy is an affordable and easy method that does not require a lot of energy and patients can continue the treatment themselves after learning how to perform the movements, and is as an alternative to costly complementary therapies after stroke. Mirror therapy can increase neuroplasticity (adaptation of nerve cells) in the brain by creating appropriate sensory inputs, and is an alternative to the lack or reduced proprioception in the affected side of the body. The aim of this study is to answer the question that mirror therapy in which subacute and chronic stages after stroke has a greater effect on patients’ walking rehabilitation?
2. Materials and Methods
This is a quasi-experimental study with pre-test/post-test design. The study population consists of all patients with stroke referred to Tabassom Clinic in Tehran, Iran (n=150). The sample size was estimated 30 according to the previous studies and the formula. Samples were 15 patients with subacute stage and 15 patients with chronic stage after stroke undergoing physiotherapy, who met the inclusion criteria and were selected using a purposive sampling method. First, the purpose and method of study was explained to each patient and then a written informed consent was obtained from them. Finally, by excluding 2 patients in the chronic group and 5 patients in the subacute group, this study was performed with 23 samples. The instruments used in this study included a demographic form and the Gait Assessment and Intervention Tool (GAIT). The demographic form had 9 questions that were completed using the patients’ medical records and interview with them. The GAIT consisted of 31 motor functions that are divided into 3 sections related to three phases of the gait cycle. The reliability of this test has been confirmed by calculating the internal consistency and inter-rater reliability and its validity has been confirmed by simultaneous evaluation with other scales. The gait of all patients was filmed in three directions: anterior, posterior and lateral; and scoring was done according to the GAIT instructions by reviewing the recorded videos. The GAIT was performed in both subacute and chronic groups before and after the intervention.
Both groups have had their interventional program for 8 weeks, 2 sessions per week for a 1.5 hours (total= 16 sessions). It consisted of 60 minutes of routine rehabilitation (nerve relaxation techniques, muscle tone adjustment exercise, muscle strength exercise, walking exercise, and weight transfer exercise), and  30 minutes of mirror therapy at 16 sessions, one session per day, in two separate parts: mirror therapy exercises and balance exercises with a mirror, each for 15 minutes. The patient did not receive any verbal feedback during mirror therapy. The difference between the experimental and control groups was only in the use of the mirror during the exercises. Data were analyzed using independent t-test and ANCOVA in SPSS version 23 software considering a significance level of 0.05.
3. Results
Mean and standard deviations of age, weight, height and GAIT score of two study groups and the results of comparison between the two groups using independent t-test are reported in Table 1.



Dependent t-test was used to evaluate the difference between pre-test and post-test scores in the two groups separately. The results showed a significant difference between pre-test and post-test scores in each group (Table 2).



To compare the results of GAIT-test in both groups in the post-test phase, considering the pre-test score as a covariate factor, the ANCOVA was used. The results showed a significant difference in the post-test GAIT score of two groups. The results also showed that the pre-test GAIT score had a significant effect on its post-test score (Table 3). 



4. Conclusion
Mirror therapy is useful for walking rehabilitation of patients with subacute and chronic stroke, but in the subacute stage it has completely better results. Therefore, it is recommended to use mirror therapy to rehabilitate the walking of stroke patients at subacute phase.
Ethical Considerations
Compliance with ethical guidelines
This article has an ethical approval from the Research Ethics Committee of Sport Sciences Research Institute of Iran (Code: IR.SSRI.REC.1399.751).
Funding
The present paper was extracted from the MSc. thesis of the first author, Department of Physical Education and Sports Sciences, Faculty of Literature and Humanities, University of Shahrekord.  
Authors' contributions
Conceptualization, methodology: All authors; Investigation, writing – original draft: Shima Shahidi, Ali Shafizadeh;  Writing – review & editing, resources: Ali Shafizadeh; Supervision: Ali Shafizadeh 
Conflicts of interest
The authors declared no conflict of interest.
Acknowledgements
The authors would like to thank the head of Tabassom Clinic and all patients for their valuable cooperation.


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