Chronic and non-communicable diseases represent major challenges of the twenty-first century, leading to severe consequences and societal issues for patients and communities across the globe. Cancer is a significant public health concern worldwide. Each year, cancer claims the lives of over 50 million people globally, with a particularly significant observation that 80% of these deaths occur in low- and middle-income countries. Cancer is impacting not only the patients but also their families and caregivers. Informal caregivers, who are often family members or close friends, play a crucial role in providing support and assistance to cancer patients. These caregivers usually have no knowledgeable medical training. The role of these caregivers is crucial throughout the entire disease trajectory of cancer patients, starting from the moment of diagnosis until the end stages of the illness. In the context of cancer, caregivers often face significant challenges related to the patient's treatment, symptom management, and fulfilling daily care needs. Caring for cancer patients can result in increased levels of caregiving burden, anxiety, depression, and reduced quality of life, which they encounter throughout their caregiving journey.

The prevalence of caregiving burden among caregivers of cancer patients is significant and well-established. A study published in India reported that 92.5% of caregivers experienced mild to severe levels of burden. Furthermore, a systematic review published in Cancer Nursing indicated that between 37% and 100% of family caregivers reported feeling a certain level of caregiver burden in various studies. Caregiving burden is negatively correlated with depression and anxiety. A systematic review highlighted that among the population of cancer caregivers, the prevalence of depression and anxiety was found to be 42% and 47%, respectively. This study indicated that nearly half of the caregivers experienced severe levels of depression (46%) and anxiety (53%). In addition, the demands of caregiving can result in physical, emotional, and social limitations, leading to a reduced overall quality of life. Previous studies reported that the burden of caregiving has a negative impact on the quality of life among caregivers of cancer patients. In Iran, another study discovered that as the quality of life among caregivers increased, there was a corresponding decrease in caregiver burden.

Over the past few years, there has been a growing interest in utilizing digital health technology, particularly mobile health (mHealth). As defined by the World Health Organization, "mHealth is a term used for medical and public health practice supported by mobile devices, such as mobile phones, patient monitoring devices, Personal Digital Assistants (PDAs), and other wireless devices". The mHealth involves various communication channels such as short messaging service (SMS), phone calls, online platforms, social networks, and emails to provide interventions. mHealth psychoeducational interventions can provide caregivers with accessible information, self-care tools, and resources specific to their caregiving journey which can improve their knowledge, skills, and self-efficacy, ultimately enhancing their capacity to manage caregiving responsibilities and their own well-being. A previous study published in the JMIR Mental Health journal showed the effectiveness of mHealth psychological interventions as a viable treatment approach for caregivers who experience high levels of stress or burden. In parallel, relaxation techniques are one of the non-pharmacological methods used to relieve mental health problems in various patients and their caregivers. Various relaxation techniques exist, and among them Benson's relaxation technique (BRT) is considered one of the most effective, low-cost, and straightforward methods of intervention. These techniques include mindfulness exercises that specifically treat a variety of mental and emotional symptoms, such as burden, anxiety, pain, depression, mood swings, and self-esteem problems. Previous studies have demonstrated the effectiveness of the BRT in reducing caregiving burden, anxiety and depression among various populations, including caregivers.

In Bangladesh, 1.3-1.5 million cancer patients which is added 0.2 million every year. Female caregivers play a vital role in providing personal support to patients. As a cultural expectation, women are generally expected to perform caregiving activities while also maintaining household responsibilities and familial commitments, which places an additional burden on them. Females in Bangladesh experience the most disadvantage and vulnerability for a multitude of reasons. Research has shown that female caregivers experience higher levels of burden and emotional distress than male caregivers, which has a substantial influence on life quality. However, the unique cultural context, gender inequalities, and social norms of Bangladesh might provide additional difficulties for these caregivers. It is essential to create effective interventions and support systems to alleviate their burden and improve their mental health and overall quality of life. To our knowledge, there is a significant knowledge gap, while there is growing evidence supporting the effectiveness of BRT and mHealth psychoeducational interventions separately, their combined impact on female informal caregivers of cancer patients remains relatively unexplored. This research protocol outlines a randomized controlled trial aimed at evaluating the effectiveness of combining the mHealth psychoeducational intervention and BRT in reducing these negative effects.

The results of this study are expected that the combination of mHealth psychoeducational and BRT will be effective in reducing caregiver burden, increasing psychological well-being, and improving overall quality of life.