Design of a randomized controlled trial of a partnership-based, needs-tailored self-management support intervention for post-treatment breast cancer survivors

Background Self-management is becoming essential for breast cancer survivors, but evidence about the effectiveness of self-management support (SMS) intervention is lacking. To address this issue, we developed a theory-based SMS intervention, the ‘EMPOWER’, aimed at empowering breast cancer survivors. Here we describe the rationale of the intervention and its development. Methods The conceptual framework of this study is the Chronic Care Model, which posits that SMS can influence patient-provider relationships and ultimately improve health outcomes. We will conduct a multi-center, 2-armed randomized controlled trial to assess the effectiveness of EMPOWER among post-treatment breast cancer survivors in South Korea. The trial will include 94 women who completed primary breast cancer treatment within the last 6 months. Participants will be randomly assigned to the intervention group or the wait-list control group (1:1). The intervention group will receive a 7-week partnership-based and needs-tailored SMS intervention via telephone counseling. The primary outcome is empowerment. The secondary outcomes include self-efficacy for post-treatment self-management behaviors, mental adjustment, psychological distress, and health-related quality of life (HRQOL). Data will be collected by self-reported questionnaire at baseline, post-intervention, and 3-month follow-up. Discussion We believe that the EMPOWER intervention could improve HRQOL of post-treatment breast cancer survivors by enhancing their empowerment. If found successful, it could aid clinicians engaged in the long-term care of breast cancer survivors. Trial registration Clinical Research Information Service, KCT0004794. Registered 5 March 2020.


Background
Breast cancer is one of most common cancers among women worldwide. Due to advances in early detection and treatment, approximately 90% of women with breast cancer survive at least 5 years after diagnosis [1]. At some point after treatment, breast cancer may be considered a chronic illness [2].
Breast cancer survivors (BCS) face the numerous health challenges that are associated with a complex chronic condition, including managing persisting symptoms, identifying signs and symptoms of progression, accessing needed information and support, and making healthy lifestyle changes [3,4]. Shouldering the responsibility for self-management (SM) behaviors can help survivors live well [5]. Unfortunately, cancer survivors in general report feelings of vulnerability and often lack the confidence to initiate the actions required to recover after their treatment [6]. This has led to increasing calls for better SM enablement.
The Chronic Care Model (CCM) is one suggested model for cancer survivorship care [7]. Introduced by Wagner and colleagues [8] in 1998, it was designed to improve the management and health outcomes of individuals with chronic illnesses. In the CCM, the essential element of good care is a productive interaction between informed, motivated patients and a prepared practice team [8]. This interaction can be influenced by 6 components of the CCM [the health system, community resources, selfmanagement support (SMS), delivery system design, decision support, and clinical information systems]. Of those 6 components, SMS has been featured as a key component for assuring quality healthcare [9]. SMS refers to support of an individual's ability to manage the symptoms, treatment, and physical, psychosocial, and lifestyle changes inherent in living with a chronic condition [8]. The application of SMS intervention among cancer survivors is increasing, and several BCS studies report its efficacy for health outcomes [10][11][12][13][14][15]. Types of SMS interventions are various and include distress management [10], uncertainty management [11][12][13], coping [14], and lifestyle management [15]. SMS interventions can significantly improve cancer knowledge [12,13], cognitive reframing [11][12][13], self-efficacy [10,15], and health-related quality of life (HRQOL) [15], and it can decrease psychological distress [10,11]. Significance has not been demonstrated, however, for SMS effects regarding empowerment [10], patient-provider communication [11,13], and social support [12], thus rendering the full efficacy of SMS intervention incomplete.
Managing everyday problems brought about by cancer and/or its treatment is likely to be enhanced by a collaborative partnership between patients and health care providers, all of whom are considered co-equal experts of the condition, albeit from different perspectives [16].
Such a collaborative approach can delineate how health care providers can support patients in their SM behaviors [6]. Given the importance of a productive interaction between patients and health care providers in chronic care, an evaluation of relationship-related outcomes such as empowerment is necessary.
In addition, the 'one-size fits all' approach for chronic disease SM may not be adequate for a chronic illness as complex as cancer. Several studies have shown that current healthcare systems do not meet the survivors' needs [17,18]. Many experts suggest that an individualized or tailored approach should be adopted in survivorship care planning [19]. Because, to the best of our knowledge, few studies have incorporated needs-tailored SMS intervention among BCS, we developed EM-POWER (PartnErship-based, tailored self-Management support Program fOr Women with breast cancER)-a partnership-based, needs-tailored SMS intervention for BCS who completed their primary treatment. The goal of EMPOWER is to enhance empowerment and increase self-efficacy for SM behaviors, thereby improving health outcomes among post-treatment BCS. This paper describes the design and methodological plan for a randomized controlled trial (RCT) to evaluate the effectiveness of EMPOWER in post-treatment BCS.

Hypotheses of the EMPOWER trial
The objective of this RCT is to test whether the EM-POWER intervention is effective, compared with a control group, in improving health outcomes (mental adjustment, psychological distress, and HRQOL) by enhancing empowerment and increasing self-efficacy for SM behaviors among post-treatment BCS.

Methods/design
The EMPOWER trial's study design and its intervention are in in concordance with the guidelines of the Consolidated Standards of Reporting Trials 2010 statement [20] and the standard protocol Items: Recommendations for Interventional Trials (SPIRIT) [21].

Study design
This study is a 2-armed RCT designed to test the effects of EMPOWER vs a control intervention. A 7-week EM-POWER intervention will be assessed at baseline (T0), 8 weeks (T1), and 20 weeks (T2). Figure 1 shows a flow chart of the RCT; Fig. 2 shows the schedule of enrollment, interventions, and assessments. The study will be undertaken in South Korea's two university hospitals-Yonsei Medical Center and Inha University Hospital. The Institutional Review Boards of both provided ethical approval. Written informed consent will be obtained from the participants.

Participants of the study
Women will be eligible to participate if they 1) are aged 19 years or more, 2) were diagnosed histologically with breast cancer, 3) were treated with a curative cancer therapy (surgery, chemotherapy, or radiation therapy), 4) completed a primary cancer treatment within the previous 6 months (except for anti-hormone therapy and targeted therapy) 5) had two or more unmet needs in a post-treatment screening test covering 12 items of unmet needs concerning SM behaviors (i.e., follow-up visit, pain management, fatigue management, insomnia management, lymphedema management, exercise, diet, smoking cessation, alcohol consumption, stress management, return to work, and sexual activity), and 6) are able to use the telephone. Women will be excluded if they had a recurrence, a metastasis, or another cancer.

Setting and procedure
Potential participants will be identified through physician-referral and self-referral. Physicians (YU Cho, S Park and MH Lee) will use electronic medical records (EMRs) to screen them for eligibility criteria related to diagnosis and treatment history and will tell potentially eligible women about the study. The researcher (YH Choe) will screen for more detailed eligibility criteria among women who are interested in participating in the study. Women who learned of our study through a flyer and are interested in participating can contact the researcher (YH Choe), who will screen them for eligibility via a telephone interview and will review medical information in the EMRs. Women who are finally eligible will meet with the researcher, and all participants will meet in the hospital and provide written informed consent.
Data will be collected via a self-reported questionnaire. After randomization, participants will complete the baseline assessment in a face-to-face interview. The researcher will contact participants via telephone 8 and 20 weeks after baseline and encourage them to complete a followup questionnaire via letter mail and send it back in an enclosed pre-addressed and stamped return envelope.

Randomization
After the baseline assessment, we will use a computergenerated block randomization procedure (block size 4, 6, 8) in a 1:1 allocation ratio to randomize participants to either the EMPOWER group or the control group. Group assignments will be placed in sealed, sequentially numbered envelopes and opened by the participants. The recruiter will thereby be blinded to the study arm assignments of the participants. Because of the social nature of the intervention, however, participants cannot be blinded to the study arm assignments.

Study groups The EMPOWER intervention group
Based on the CCM, EMPOWER involves providerparticipant partnerships. Such partnerships that help participants play a larger role in managing their posttreatment medical problems, thereby helping them reach their care goals [7]. SMS empowerment can extend to late and long-term treatment effects as well, helping survivors understand when to seek support and encouraging healthy lifestyle changes [6].
Participants in the EMPOWER group will receive a 7week partnership-based, needs-tailored SMS intervention via telephone counseling (ten 15-to 20-min sessions, totaling 175 min). We extracted the intervention program contents from the conceptual SM framework in chronic illness [22], the qualitative data from a Korean BCS focus group interview regarding post-treatment SM needs [23] structured by 5 SM tasks (medical management, symptom management, lifestyle management, emotional management, and role management) and 21 specific topics (Table 1). An expert advisory team (3 surgeons, 1 advanced practice nurse, and 1 nursing professor) validated the final thematic structure.
The EMPOWER intervention is subdivided into a 3week SM education part and a 4-week SM skill training part (Table 2). At the end of the education part, participants will receive SM skill training in the topic of their choice. Currently, we have modules for the 6 topics (pain, fatigue, insomnia, exercise, diet, and distress) we have accumulated evidence for the intervention. Through participant choice, providers can tailor SM skill training to individual needs. Using a 96-page evidence-and theory-based workbook, master-level nurses will deliver the SM education and skill training by telephone. The education and action planning contents of the workbook were extracted from the Korean National Cancer Information Center [24], the National Comprehensive Cancer Network [25], and the Oncology Nursing Society [26]. During the education sessions, providers will exploit Badura's selfefficacy sources [27], such as verbal persuasion, vicarious experience, mastery, and physiological states. The workbook, for example, includes various vicarious experiences leading, for example, to success in weight management, exercise performance, and work resumption. During the SM skill training sessions, providers will present Lorig and Holman's SM skills of problem solving, decision-making, taking action, forming partnerships, and utilizing resources [22]. The training uses a structured module according to a weekly plan (Table 3).  The participant workbook is composed of a structured format that includes problem identification, goal setting, action planning, resource identification, and action monitoring. Facilitation of provider-participant partnerships is provided by a telephone counseling module that uses motivational interviewing principles (i.e., open questions, affirmation, reflective listening, and summary reflections) [28].

The control group
Participants in the control group will receive a 51-page education book whose content is the same as Part 1 of the intervention workbook. It includes SM strategies after cancer treatment but excludes SM skill training. At the end of the study, the control group can request the intervention.

Study outcomes
The overview of the psychometric properties of primary and secondary outcome measures is presented in Table 4.

Primary outcome
We will evaluate empowerment using the Empowerment Scale for Women with Breast Cancer [29]-a 30-item self-report instrument consisting of intrapersonal factors (14 items), interactional factors (8 items), and behavioral factors (8 items). Scored on a 5-point Likert scale, a high score indicates higher empowerment. The scale has shown good validity and reliability [29].

Secondary outcomes
We will measure self-efficacy for SM among BCS using a Korean version of the Cancer Survivors' Self-Efficacy Scale (CSSES-K) [30]. The original version of CSSES is an 11-item questionnaire assessing cancer survivors' cancer-related self-efficacy [31]. The CSSES-K is a 10item, 2-factor questionnaire. The factors are 'self-efficacy for managing health problems' (5 items) and 'self-efficacy for seeking help and support' (5 items) [30]. Each item is rated on a 10-point scale from 1 (not at all Mx management, NCCN National Comprehensive Cancer Network confident) to 10 (totally confident); a higher score indicates higher self-efficacy. The original version of CSSES has a good reliability and validity [31], thus the CSSES-K has adequate internal consistency (Cronbach's alpha = 0.86-0.92) [30]. We will evaluate mental adjustment using a Korean version of Mini-Mental Adjustment to Cancer (Mini-MAC) [32]. Anxiety and depression will be assessed using the Hospital Anxiety and Depression Scale (HADS) [34]. HADS is a 14-item self-report instrument assessing symptoms of anxiety and depression that reflects 2 subscales, with 7 items for depression and 7 items for anxiety. Each item is scored from 0 to 3, with higher scores indicating more distress. The Korean HADS has been validated and has shown good validity and reliability [35].
We will measure HRQOL using the 36-item Short-Form Health Survey (SF-36) [36]-a 36-item questionnaire that consists of 2 domains (physical and mental) and 8 subscales (functioning, physical role functioning, bodily pain, general health, vitality, social role functioning, emotional role functioning, and mental health). Each subscale is scored from 0 to 100, with higher scores indicating better functioning and well-being. The SF-36 has been translated into Korean and shown good validity and reliability [37].

Sample size calculation
Based on the primary outcome 'empowerment', at least 78 patients will be required using an effect size of 0.65 [38], a power of 0.8, and an alpha less than 0.05. Assuming an estimated dropout of 20%, 47 participants will be needed in each group (a total of 94 participants).

Statistical analysis
We will describe the characteristics of the study participants using frequency and percentage for categorical variables and means and standard deviations for  [29].

Secondary outcomes
Self-efficacy Korean version of the Cancer Survivors' Self-Efficacy Scale 10 items and 2 factors. Factors include 'Self-efficacy for managing health problems' (5 items) and 'selfefficacy for seeking help and support' (5 items). 10point Likert scale. Higher score indicates higher selfefficacy.
CFI comparative fit index, HRQOL health-related quality of life, RMSEA root mean square error of approximation, SRMR standardized root mean square residual, TLI Tucker-Lewis Index continuous variables. To compare baseline characteristics between the two groups, we will use independent ttests for normally distributed continuous variables, the Mann-Whitney test for non-parametric variables, and the chi square test for categorical variables. We will use linear mixed models to analyze the efficacy of EM-POWER and Cohen's d to estimate effect size as large (≥0.80), moderate (0.5-0.79), or small (< 0.50) [39]. Missing data will be handled under the missing-atrandom assumption. We will perform all analyses using IBM SPSS Statistics version 25.0 (IBM, Armonk, NY, USA) according to the intention-to-treat principle and consider a p-value < 0.05 significant.

Discussion
We developed the EMPOWER intervention with the intention of improving health outcomes by enhancing empowerment and increasing self-efficacy in posttreatment BCS, thus facilitating successful transition from hospital-based survivorship care to SMS care. Expected outcomes include decreased psychological distress, better mental adjustment, and improved HRQOL. If successful, this study will provide evidence that SMS may be an important survivorship care model. EMPOWER has several strengths. First, it is theorybased; we applied self-efficacy theory [27], Lorig and Holman's model [22], and motivational interviewing technique [28] for development and delivery of the intervention. EMPOWER's main mechanism will be to facilitate partnership between provider and participant and increase self-efficacy of the participant. Second, EM-POWER is needs-tailored. Although substantial BCS have unmet needs after cancer treatment [40,41], there is a lack of interventions that meet their supportive care needs in a personalized manner. We believe that EM-POWER's Part 2 intervention (4-week SM skill training for participant's chosen topic) will work as a needsbased tailored intervention. Third, EMPOWER's SM skill training protocol is evidence-based. We developed action-planning protocols for each SM topic based on interventions that were already proven effective.
EMPOWER has also several weaknesses. First, it can be resource intensive because it is delivered by a welltrained nurse via telephone. That burden could be reduced, however, by delivering the Part 1 intervention (SM education) by an app or on the web. Second, SM skill training is available for only 6 topics (management of pain, fatigue, insomnia, distress, exercise, and diet). As more evidence becomes available, other SM topics could be developed. Third, generalization to a wider setting and in other countries must be done with caution because the prioritized SM topics were chosen by the Korean population.

Conclusion
EMPOWER is a theory-based SMS intervention unique in its provider-partnership and needs-tailored approach. If found successful, the EMPOWER trial will offer insights into how clinicians can engage in chronic care for BCS after treatment using SMS intervention.