Design and setting
This two-armed controlled clinical trial study was conducted in Shiraz in southern Iran. The study protocol was written in accordance with the CONSORT guidelines [22]. This study was conducted in the Breast Disease Research Center that is one of the largest breast disease research and treatment centers in southern Iran, which has annually over 25,000 visitors from different parts of the country.
Eligible criteria
The study participants were recruited from women with breast cancer who referred to the Breast Disease Research Center. The inclusion criteria admitted (a) adults 20–70 years of age, (b) being treated for a diagnosis of breast cancer, (c) mild to moderate depression score by the Beck Depressive Inventory and (d) the ability to attend sessions according to the oncologist. The exclusion criteria were absence from treatment sessions, death, and severe psychological or physiological conditions coinciding with the period of psychotherapy.
Estimation of sample size was set at 12 participants in each treatment arm, assuming a standard difference of 1.2 points on the primary outcome, and considering a bilateral significance level of 5% and a statistical power of 85%, adjusted by a dropout rate of 20%. The estimation of sample size was based on a study by researchers who reported the mean and standard deviation of depression in control and intervention groups 21 ± 1.4 and 19.50 ± 1.5, respectively [23].
Measurements
At baseline, the patients’ demographic data (age, marital status, occupational status, educational status, place of residence, history of depression, history of hospitalization, duration of cancer, type of cancer therapy, history of psychotherapy and frequency of fertility) were evaluated using a demographic questionnaire.
Primary outcome
The primary outcome measure was changed in depression score, and measured at baseline (T0), immediately after (T1), and one month after the intervention (T2) using the Beck Depressive Inventory (BDI). The BDI is a 21-item self-report rating inventory measuring characteristic attitudes and symptoms of depression. The questionnaire is designed for adults and adolescents over 13 years old. The person is asked to consider his or her feelings in the last two weeks and answer the questions. The 4-point Likert scale is from 0 to 3 for each question. This scale determines the degree of depression from mild to very severe. The score ranges from at least zero to at most 63. Internal consistency for the BDI ranges from 0.73 to 0.92 with a mean of 0.86. The BDI demonstrates high internal consistency, with alpha coefficients of 0.86 and 0.81 for psychiatric and non-psychiatric populations, respectively [24]. The BDI-Persian had high internal consistency (Cronbach’s alpha = 0.87) and acceptable test–retest reliability (r = 0.74) [25]. The BDI takes approximately 10 min to complete (see Additional file 1).
Secondary outcomes
Cognitive emotion regulation questionnaire (CERQ)
This 36-item questionnaire evaluates the cognitive strategies that each person uses after experiencing threatening events or life stresses. This scale consists of the following 9 sub-scales, each consisting of four items and each referring to what someone thinks after experiencing threatening or stressful life events: self-blame, other-blame, rumination, catastrophizing, putting into perspective, positive refocusing, positive reappraisal, acceptance, and planning. Cognitive emotion regulation strategies were measured on a 5-point Likert scale ranging from 1 (almost never) to 5 (almost always). Individual subscale scores were obtained by summing the scores belonging to the particular subscale (ranging from 4 to 20). The total score is placed in the range of 36–180. The psychometric properties of the CERQ were studied in an adult general population sample. The results indicated that the CERQ had good factorial validity and high reliability, with Cronbach’s alpha ranging from 0.75 to 0.87 [26]. This questionnaire is a valid, reliable, and appropriate instrument to detect and assess cognitive strategies in Iranian patients [27] (see Additional file 2).
Meta cognitions questionnaire (MCQ)
The MCQ-30 is a short version of the original MCQ measuring individual differences in a selection of meta-cognitive beliefs, and judgments as well as monitoring tendencies considered important in the meta-cognitive model of psychological disorders. The questionnaire is 30-item, 4-point Likert, and self-report scale. The questionnaire has five subscales. The five subscales of the MCQ-30 are: cognitive confidence, positive beliefs in worry, cognitive self-consciousness, negative beliefs in the uncontrollability of thoughts and danger, and beliefs in the need to control thoughts. Subscale scores range from 6 to 24, and total scores range from 30 to 120, with higher scores indicating higher levels of unhelpful metacognitions. Subscales are calculated by summing the following item: lack of cognitive confidence: 8, 14, 17, 24, 26 and 29; positive beliefs in worry: 1, 7, 10, 19, 23 and 28; cognitive self-consciousness: 3, 5, 12, 16, 18 and 30; negative beliefs in uncontrollability and danger: 2, 4, 9, 11, 15 and 21; need to control thoughts: 6, 13, 20, 22, 25 and 27. The MCQ-30 exhibited good internal consistency, convergent validity, and acceptable to good test–retest reliability [28]. The Cronbach's alpha coefficient of the subscales varied from 0.72 to 0.93. The Cronbach's alpha coefficient of the total scale in the Iranian sample has been reported as 0.91 [29] (see Additional file 3).
Blindness and randomization
Owing to the nature of meta-cognitive therapy, neither the therapist nor the participants can be blinded to the delivered treatment. Data collectors and data analyzers were blind to group membership.
Participants were randomized on a 1:1 basis into the intervention group (meta-cognitive therapy) or the control group (Treatment As Usual; TAU). To randomly allocate the participants to one of the two groups (intervention and control), a computer-generated random number sequence (https://www.randomizer.org/) was used by means of a simple allocation strategy. A statistician not involved in the study performed the randomization.
Interventions
This study was conducted in the fall and winter of 2017. The participants were recruited from patients with breast cancer who referred to the Breast Cancer Disease Research Center. Patients with breast cancer who had mild to moderate depression, were enrolled as participants based on the Beck Depressive Inventory. After obtaining informed consent, samples provided their phone numbers and addresses to participate and announce the time, date and place of the therapy sessions by phone (education place was at the Breast Disease Research Center). The samples were randomly allocated to two experimental and control groups. Initially, the pretest (MCQ-30 and CERQ) was conducted to obtain the basic data. Then, eight 90-min sessions were held for the intervention group in addition to TAU (Table 1). Each week, a session was held in groups with assignments during and between sessions for this group of samples. The control group received treatment as usual. TAU consisted of providing the usual treatment to patients according to accepted standards for depression (except psychotherapy, which will not be allowed 6 months before the study or during it). Post-test was conducted after completing the sessions and one month later from both groups. The method of teaching was a lecture, group discussion, role play, and homework according to Welles' educational program [30].
Ethical considerations
The study has been performed in accordance with the Declaration of Helsinki and has been approved by the Ethics Committee of the Research Deputy of Bushehr University of Medical Sciences with the ethics code [IR.BPUMS.REC.1395.52]. After a brief explanation about the objectives of the study for the participants, written informed consent was obtained from study participants. Confidentiality was ensured.
Data analysis
Data were analyzed using descriptive statistics (frequency, mean and standard deviation) and inferential statistics via SPSS23 (SPSS, Inc., Chicago, IL, USA) software at a significance value less than 0.05. The distribution of variables was analyzed by the Kolmogorov–Smirnov test at a significant value of 0.05. Since the distributions of the studied variables were not normal, non-parametric statistical tests such as Chi-square for comparison of demographic variable, Mann Whitney for between-group comparison, and Wilcoxon and Friedman tests for within-group comparisons were used to analyze the data.