2.1 Study Design
Randomized controlled intervention study.
2.2 Study sample
The study population consisted of patients diagnosed with breast cancer, who received radiotherapy in the radiation oncology unit of a hospital in Ankara, between June 01, 2017 and January 31, 2019.
The sample size was calculated with the G*Power (G*Power, Ver. 3.0.10, University Kiel Germany software program (http://www.psycho.uni-duesseldorf.de/aap/projects/gpower/) using preliminary study data since there are no similar studies in the literature. A preliminary study was conducted for each of the three groups containing eight, eight and seven participants, respectively. In the variables, the lowest effect width was determined as 0.25 and the highest effect width was 0.62. As a result of the analysis on fatigue and insomnia, which was the main variable in the study, the number of groups were determined as three, the repetitions to be carried out as two, type I error rate as 0.05, the power of the study as 0.95. The minimum number of volunteers required to determine the difference between the three groups with an effect width of f=0.25 was determined as 54 individuals (18 in each group). At least three additional volunteers (16%) for each group were added, considering monitoring and data loss during the follow-up. Thus, the number of subjects was determined as 63 individuals (21 for each group).
Of the 63 patients, one wanted to interrupt the treatment and two did not want to continue in the study, hence the study was concluded with 20 patients in each group (60 patients) (Figure 1).
Literate patients over the age of 18 years, who underwent breast resection or modified radical mastectomy, were planned for radiotherapy for the chest wall/breast and lymphatic area, had Stage II-III breast cancer according to the TNM (Tumor diameter, Node, Metastasis) classification system, had a hemoglobin (HgB) level of 10 gm/dL and above, scored 0 or 1 on the ECOG (Eastern Cooperative Oncology Group) Performance Scale and who agreed to participate in the study were included in the sample. Exclusion criteria included; having any problems that would prevent communication, having stage IV breast cancer according to the TNM classification system, using opioids or sedating drugs, scoring above 1 on the ECOG Performance Scale, having psychiatric illnesses, taking yoga/pranayama/deep breathing exercise lessons before or having done these exercises prior to diagnosis, having recurrent breast cancer and being unable to perform the exercises due to physical inability/respiratory distress. Interruption of the treatment regimen due to any complications, participation in less than 20 of the 25 sessions and the desire to leave the study were determined as termination criteria.
Individuals, who met the inclusion criteria, were assigned to the groups using a simple randomization method with a closed envelope. Individuals were asked to complete the data collection forms themselves. Those, who were not able to do so received support from a nurse within the unit.
Descriptive characteristics questionnaire: This form contained seven questions regarding the patients’ descriptive characteristics (age, educational status, type of surgery etc.) and was created by the researchers in line with the literature [14, 23, 32, 42].
Fatigue Visual Analog Scale (VAS) Score: This scale which evaluates the severity of fatigue, was scored as follows: no fatigue= 0 points, mild fatigue= 1-3 points, moderate fatigue= 4-6 points, severe fatigue= 7-9 points and unbearable fatigue= 10 points.
Piper Fatigue Scale (PFS): This scale consisted of 22 items and evaluated the patient’s subjective fatigue perception with four subdimensions. Each item was scored between 0 and 10. A high score obtained from the scale indicated a high level of perceived fatigue. The Turkish validity-reliability study of the scale was carried out by Can [43,44]. In this study, the Cronbach’s alpha internal consistency coefficient was found as 0.98.
Insomnia Visual Analog Scale (VAS) Score: The scoring system of this scale was as follows: no insomnia= 0 points, mild insomnia= 1-3 points, moderate insomnia= 4-6 points, severe insomnia= 7-9 points and unbearable insomnia= 10 points.
Pittsburgh Sleep Quality Index (PSQI): PSQI is a self-report-based screening and evaluation tool that provides detailed information on sleep quality and type and severity of sleep disorder in the past month. The scale consists of 24 questions and seven components to evaluate subjective sleep quality, time it takes to fall asleep, sleep time, habitual sleep efficiency, sleep disturbance, use of sleeping pills and daytime dysfunction. The total PSQI score could vary from 0 to 21. A PSQI score over 5 points indicated that the person suffered serious problems in at least two areas related to sleep or that they suffered mild to moderate problems in more than three areas . The validity and reliability study of the index was carried out by Ağargün et al.. In this study, the Cronbach’s alpha internal consistency coefficient was found as 0.80.
Questionnaire on Patients’ Opinions of the Exercises: A form consisting of ten questions prepared by the researcher to determine the opinions of the patients on the feasibility and results of the exercises (difficulties in learning and doing the exercises, satisfaction with doing the exercises, etc.). The opinions of patients in the pranayama and deep breathing exercises groups were taken at the end of radiotherapy treatment.
Patients in the pranayama, deep breathing exercise and control group were evaluated six times in terms of fatigue and insomnia VAS scores. One time prior to the start of the 25-day session of radiotherapy treatment, four times during the radiotherapy treatment process (at the 1st through the 4th week) and one time at the end of the treatment. PFS and PSQI were evaluated once prior to and after the 25-day session of radiotherapy treatment.
Protocols for pranayama and deep breathing exercises were prepared in line with the literature and the intervention was carried out (Figure 2). Prior to develop the protocol, certified training was received by the researcher for breathing exercises. Written opinions were received from seven experts regarding the content validity in order to evaluate the protocols in terms of expression, clarity, coverage and whether scientific errors are present. Following the opinions, the protocol content was edited and finalized.
Pranayama and Deep Breathing Exercise Groups: The patients were taught pranayama and deep breathing exercises by the researcher before the radiotherapy started. The patients were observed performing these exercises for 10 minutes after each radiotherapy session (25 days) accompanied by the researcher in a quiet room within the radiotherapy unit containing two couches and a chair.
Control Group: The patients in this group did not receive any intervention.
2.5 Statistical analysis
Statistical analyses were made using IBM SPSS for Windows Version 21.0 software program. The compatibility of numerical variables to normal distribution was examined by using Kolmogorov-Smirnov and Shapiro-Wilk tests. Numerical variables that conform to normal distribution were reported using mean ± standard deviation and numerical variables that do not conform to normal distribution were reported using the median [minimum- maximum] values. In terms of numerical variables that conform to normal distribution, comparisons between groups were analyzed with one-way analysis of variance (ANOVA), taking into account the number of groups to be compared. Kruskal-Wallis test was used for comparison of numerical measurements that do not conform with normal distribution. Wilcoxon test was used for comparisons in dependent groups. The comparison of categorical variables between groups was examined with the Chi-Square test. Bonferroni-corrected Post-Hoc tests were used to identify the groups that made the difference in comparisons between groups with significant differences. The statistical significance level for all hypothesis tests was set at 0.05 and below.
2.6 Ethical Considerations
Ankara Yıldırım Beyazıt University Ethics Committee gave permission (study code: 486, approval date: 31.03.2017, number: 28) and the scientific committee of the hospital where the study was performed gave permission for the study. Patients gave written informed consents.