Music Intervention Can Improve Emotion in Cancer Patients during Disease Progression

Music has long been regarded to aid health and loss-adaptation, but effect of music intervention on cancer patients is not well-understood. The aims of this study are to summarize and describe the role of music before and after diagnosis. This review examines music intervention studies with randomized designs for patients with cancer published between 1991 and 2015 from three Englishlanguage databases and Chinese-language databases. Ten studies that met specific inclusion criteria were reviewed. Our review indicates that music intervention may have beneficial effects on emotion (anxiety/depression) in patients with cancer. More research is needed to ascertain the most optimal intervention methodology on which cancer populations or which treatment modalities are appropriate for such an intervention.


Results
Initially, 277 articles were collected and 88 articles among them were included according to the inclusion and exclusion criteria. The titles and abstracts were then read one by one. 10 articles were selected for the final review and delivered on one occasion [15][16][17][18][19][20][21][22][23][24]. Most of the studies (90%) reported significantly emotion improvement after music treatment compared with the control group. Only one study (10%), however, reported no significance between the two groups. The effects of music intervention mentioned in the included studies were analyzed in detail as follows. (Figure 1)

Introduction
Emotional distress in cancer patients happens during their acute treatment and after treatment ends [1,2]. Some cancer patients were reported to have positive results after treatment. However, many patients suffered severe traumatic stress and showed regressive, withdrawn and angry behaviors [3][4][5][6]. Non-pharmaceutical interventions play an important role in alleviating these symptoms, including pain, depression, anxiety, and poor quality of life during the treatment of cancer [7][8][9]. Among these complimentary interventions, music intervention attracted a lot of attention from both patients and clinicians for fewer side effects and being cost effective [10][11][12]. This review summarizes evidences supporting effects of music intervention from clinical trials, and presents challenges and opportunities for further research and studies in this emerging area.

Design
This study is a literature review about music interventions to manage emotion changes in cancer patients. The current studies with different designs will be synthesized to address the issue. Thus, the inclusive articles should follow the following inclusion criteria and exclusion criteria.

Inclusion CriteriFull articles published from 1991 to 2015 in
English and Chinese.

Trials used a RCT design and tested a music intervention.
3. Sample studies were human subjects of any age.  [25][26][27][28]. Thus, standard is recommended for the intervention quality control, in which the researchers can reduce the dropout rate reported in previous studies [29,30].

Exclusion
The included 10 studies were all random assignments and specified eligible criteria. Only one study reported double blind trial, namely blind subjects and blind therapists. Thus, the placebo effects could not be ignored in the majority of studies. The interventions applied in the studies varied in content, duration, and dose. Most interventions were individualized according to the needs of subjects and therapists.
Through this review, despite having limited investigations in this field, we found that a much stricter methodology should be highlighted and paid attention to [31]. In addition, diverse methodologies were found in the studies which affected the heterogeneity of metaanalysis and review article [32][33][34]. For example, the present review article could hardly make a conclusion on the effects of music-based intervention due to different cancer types, genders, and measurement tools.

Perspective
Specifically, more conceptual and mechanisms studies of this field are needed. To get an optimal intervention for cancer populations, it is urgent for the researchers to obtain identification of methodological components because inconsistencies would block the development of music therapy. Different results from various studies, which might contribute to various cancer types, different cancer stages, various treatments, and different intervention durations, should be explored for the psychological beneficial of cancer patients in the future investigations. Additionally, theoretical framework, which can provide rationale for the intervention of cancer patients, should also be highlighted and paid attention to. Homogenous populations, including cancer types and cancer stages, and intervention durations, should be considered for the future clinical translation.