Development Of Dietary Self-management Behavior Questionnaire And Effect Evaluation Of The Supportive Intervention For Breast Cancer Patients During Chemotherapy

ObjectiveDiet is closely related to the health-related quality of life for breast cancer patients.Chemotherapy,with its associated toxic and side effects,often disrupts daily food intake behavior,impeding the consumption of necessary nutrients and adversely affecting treatment compliance and later recovery.The importance of active participation by breast cancer patients in managing their own diet during chemotherapy has grown more evident.However,specific assessment tools are lacking,and there is a notable absence of comprehensive,scientifical and tailored interventions for supporting dietary self-management.In light of these considerations,this study delves into the health behavior changes and dietary characteristics of breast cancer patients undergoing chemotherapy,particularly within the cultural context of China.The research following:1.To formulate and validate the Dietary Self-management Behavior Questionnaire tailored for breast cancer patients undergoing chemotherapy,aligning with the specific dietary culture and characteristics prevalent in China.This questionnaire aims to serve as a valuable tool,enabling the early identification of shifts in dietary self-management behavior among breast cancer patients during chemotherapy.Additionally,it seeks to effectively assess the impact of related supportive interventions.2.Employing the developed questionnaire,the study aims to investigate and outline the present scenario and influencing factors related to the dietary self-management behavior of breast cancer patients undergoing chemotherapy.By elucidating its performance and identifying key factors,this research seeks to establish a theoretical foundation for crafting tailored dietary self-management support interventions.3.Utilizing the questionnaire content and identified key factors,the study aims to devise a comprehensive supportive intervention for the dietary self-management behavior of breast cancer patients.This intervention will be developed through collaboration with a multidisciplinary team.The research further seeks to investigate the effectiveness of this program in enhancing early dietary self-management behavior,self-care self-efficacy,and the overall quality of life among female participants,while also maintaining their body mass index.Methods1.Part One:Development and Validation of a Formal Version of the Dietary Self-management Behavior Questionnaire for Breast Cancer Patients Undergoing Chemotherapy.Drawing from an evidence-based perspective and employing the steps outlined in the scoping review methodology framework,this phase utilized the"Capacity,Opportunity,Motivation-Behavior Model"（COM-B）as theoretical guidance.Qualitative descriptions and summaries of included literature were conducted,focusing on dietary self-management behavior and related elements of breast cancer patients.From this,preset dimensions and an item pool for the questionnaire were derived.Building on insights from previous tools and considering the dietary culture in China,two rounds of Delphi expert consultations and patient pre-survey were conducted.This process led to local modifications and quantitative deletions of items,resulting in the initial draft of the Dietary Self-Management Behavior Questionnaire for breast cancer patients undergoing chemotherapy.Following the established process for developing assessment tools,the initial draft of the questionnaire underwent three survey rounds among hospitalized breast cancer patients undergoing chemotherapy in Grade A tertiary hospitals in Xi’an and Zhengzhou cities for further refinement and validation.In the first round,a comprehensive analysis,including ceiling and floor effects,five methods（high and low group t-test,discrete trend method,exploratory factor analysis,correlation coefficient method,and Cronbach’sαcoefficient method）from the Classical Test Theory（CTT）.This analysis guided the selection of items based on sensitivity,representativeness,discrimination and stability,resulting in a trial questionnaire.Then,the trial questionnaire was employed for a second survey.Using the same item selection methods,items were further screened based on survey data.Dimensions were then determined through factor analysis and parallel analysis,leading to the formation of the formal version.The final round involved a survey to verify the reliability,validity,and discrimination of the formal questionnaire.2.Part Two:Current Status and Influencing Factors of Dietary Self-management Behavior in Breast Cancer Patients during Chemotherapy.Drawing insights from the“Common Sense Model of Self-regulation”（CSM）and“the Integrated Theory of Health Behavior Change”（ITHBC）,this segment focused on identifying potential influencing factors affecting the dietary self-management behavior of breast cancer patients during chemotherapy by using Dietary Self-Management Behavior Questionnaire.Various analysis methods,including independent sample t-tests,one-way analysis of variance,Pearson correlation analysis,and multiple linear regression,were utilized.The research aimed to explore the impact of demographic factors,disease and treatment-related factors,self-care self-efficacy,outcome expectations,treatment self-regulation,and perceived social support on the dietary self-management behavior of breast cancer patients during chemotherapy.3.Part Three:Construction and Effect Evaluation of Dietary Self-management Support Intervention for Breast Cancer Patients during Chemotherapy.Building on insights gained from the scoping review of intervention studies,along with the key influencing factors identified in dietary self-management behavior and theoretical guidance,the initial draft of the intervention was formulated.The first draft underwent scrutiny through expert consultation and a pilot study involving female participants.Subsequent modifications based on feedback led to the final draft of the intervention.A single-center randomized controlled trial was conducted.Breast cancer patients meeting inclusion criteria and undergoing chemotherapy in a tertiary hospital in Xi’an on June-July2023 were recruited.Enrolled patients were randomly assigned to either the intervention group or the control group using a random number table at 1:1 ratio.The primary outcome indicators included dietary self-management behavior and quality of life,while the secondary outcome indicators included self-care self-efficacy and BMI.Various measures,including independent sample t-tests,Mann-Whitney U tests,and Generalized Estimating Equations analysis,were employed to assess the differences and changes in dietary self-management behavior,self-care self-efficacy,quality of life,and Body Mass Index（BMI）at baseline（T₀）,immediately post-intervention（T₁）,one month after the intervention（T₂）,and three months after the intervention（T₃）.The effectiveness of the intervention was evaluated.Results1.Part One:Development and Validation of a Formal Version of the Dietary Self-management Behavior Questionnaire for Breast Cancer Patients Undergoing Chemotherapy.In this scoping review,a total of 54 articles meeting the criteria.Summarizing the included literature and extracting similar behavioral performances guided by the COM-B model resulted in the identification of 6 first-level themes and 25 second-level themes.These first-level themes were"weight management,""adverse reactions coping,""dietary nutrition supplement and replacement,""dietary information seeking,""selective food intake,"and"dietary habit regulation".These first-level themes were then established as the preset dimensions for the Dietary Self-management Behavior Questionnaire for breast cancer patients during chemotherapy.Furthermore,important conditions involved in dietary self-management behavior were extracted and summarized into a three-level theme.Combining this information with reference to existing relevant tools and items,an item pool containing 135 items was formed for this study.Through two rounds of Delphi expert consultation and a patient pre-survey,items underwent modifications,including additions,deletions,or adjustments.The final result was the creation of the first draft of the Dietary Self-management Behavior Questionnaire for breast cancer patients during chemotherapy,comprising 6 preset dimensions and a total of 98 items.A total of 158,385 and 771 breast cancer patients participated in the first,second and third round of survey respectively,and150,378 and 760 valid questionnaires were effectively returned.Through the ceiling and floor effect test,five item screening methods based on the CTT for two times of item screening,factor analysis and parallel analysis,the Dietary Self-management Behavior Questionnaire for breast cancer patients with chemotherapy was officially produced.The questionnaire had 22 items and 4 dimensions,including"adverse reactions coping"（4 items）,"dietary information seeking"（5 items）,"dietary nutrition supplement and replacement"（5items）and"dietary habit regulation"（8 items）.The results of exploratory factor analysis and confirmatory factor analysis showed that the actual structure of the questionnaire was consistent with the number of dimensions envisaged in advance,and the cumulative variance contribution rate of the four factors reached 62.67%.The norm of fit index（NFI）was 0.89（close to 0.90）,and the other indicators met the statistical requirements.The correlation coefficients between the scores of each dimension were mostly distributed in the range of 0.201 to 0.543,and the correlation coefficients between the scores of each dimension and the total score of the scale were 0.697 to 0.751,which were all positively correlated.The correlation coefficients between the scores of each dimension and the total score were basically greater than the correlation coefficients between the dimensions.The Content Validity Rate（CVR）was 0.62.The Cronbach’s a coefficient of the total scale was0.908,the split-half reliability coefficient was 0.833,and the test-retest reliability coefficient of 114（15%of the total sample）subjects after two weeks was 0.938.There were statistically significant differences in the scores of each dimension of the questionnaire among females with different ages,education levels,BMI,menopausal status and cancer stages（P<0.05）.2.Part Two:Current Status and Influencing Factors of Dietary Self-management Behavior in Breast Cancer Patients during Chemotherapy.The overall score for dietary self-management behavior among breast cancer patients undergoing chemotherapy was 69.60±11.12.The average scores for the four dimensions were 27.49±4.61 for dietary habit regulation,15.26±3.53 for dietary information seeking,14.78±3.85 for dietary nutrition supplement and replacement,and 12.07±2.78 for adverse reactions coping.Positive attitude,stress relief,self-decision making,future orientation,autonomous motivation,introversive regulation,and support from friends and others were identified to be positively correlated with both the total score and individual dimension scores of dietary self-management behavior.Immediate orientation and amotivation were negatively correlated with both the total score and individual dimension scores.Multiple linear regression analysis revealed that key influencing factors for dietary self-management behavior among breast cancer patients during chemotherapy included the number of children,family monthly income per capita,living environment,employment status,positive attitude,self-decision making,immediate orientation,future orientation,autonomous motivation,introversion regulation,amotivation,and support from friends and others（adjusted R²=51.1%,P<0.05）.3.Part Three:Construction and Effect Evaluation of Dietary Self-management Support Intervention for Breast Cancer Patients during Chemotherapy.The intervention was developed based on the theoretical guidance of ITHBC,incorporating dimensions from the questionnaire and insights from the main influencing factors.The final version was refined through expert consultation and a patient pilot study.The intervention,delivered by a trained multidisciplinary team,consisted of eight sessions occurring weekly,with each session lasting 30-45 minutes.The intervention utilized a combination of face-to-face and online formats,catering to both group and individual settings.Core themes of the interventions encompassed“coping management of adverse reactions,dietary information and habits education,enhancement of self-care self-efficacy,treatment self-regulation training,dietary nutrition supplement and replacement education,social support education,weight management guidance,and outcome expectation training”.For the randomized controlled trial,88 eligible breast cancer patients undergoing chemotherapy in a Grade A tertiary hospital in Xi’an were recruited.A total of 44 females were included in the two groups.Finally,40 patients completed the intervention in the intervention group and 39 patients completed the intervention in the control group.At baseline（T₀）,there were no significant differences in all indicators between the intervention and control groups（P>0.05）.There were statistically significant differences in the main effect of intervention in the total score and scores of each dimension of dietary self-management behavior,the total score of self-management efficacy and the total score of quality of life before and after intervention（P<0.05）.The main effect of time in patients in each group was statistically different（P<0.05）.There was an interaction between intervention factors and time factors in the two groups（P<0.05）.However,in the intervention group,there was no significant difference in BMI at T₁,T₂,and T₃ compared with T₀（P>0.05）.Conclusions1.The Dietary Self-management Behavior Questionnaire for breast cancer patients undergoing chemotherapy consisted of 4 dimensions and 22 items,namely"dietary habit regulation","dietary information seeking","dietary nutrition supplement and replacement"and"adverse reactions coping".The questionnaire demonstrated robust reliability,validity,and discrimination when applied to breast cancer patients undergoing chemotherapy in China.2.The dietary self-management behavior of breast cancer patients during chemotherapy in China requires enhancement,particularly in the realms of dietary nutrition supplementation and replacement,coping with adverse reactions,and seeking dietary information.These specific areas merit consideration in the development of relevant intervention content.Notably,factors influencing dietary self-management behavior include fewer children,lower family income,rural residence,unemployment,negative attitude,inadequate self-decision making,immediate orientation as the primary outcome expectation,lack of motivation for treatment self-regulation,and limited friends and other support.Individuals with these characteristics are more likely to exhibit suboptimal dietary self-management behavior,making them a pivotal target population for future dietary self-management support interventions.3.The dietary self-management support intervention delivered by the multidisciplinary team showcased positive effects,enhancing the levels of dietary self-management behavior,self-care self-efficacy,and quality of life among patients.However,it did not yield a significant impact on the BMI of participants from the intervention group.Innovations1.From the perspective of health behavior change and specific lifestyle adjustment,it was the first to analyze the problems of breast cancer patients during chemotherapy with high demand for dietary support,but unclear management behavior,and insufficient dietary support.2.Based on the CTT,the Dietary Self-management Behavior Questionnaire for breast cancer patients during chemotherapy was first developed,which was in line with the diagnosis,treatment and diet characteristics of breast cancer patients during undergoing chemotherapy in China.The questionnaire has good reliability,validity and discrimination,which can be used in the related research.3.By combining the internal and external factors in the theories related to health behavior change,Chinese diet culture and the actual situation of breast cancer patients during chemotherapy,the dietary self-management support intervention for breast cancer patients with comprehensive and specific elements was designed,and carried out the evaluation to prove its effectiveness on improving the dietary self-management behavior,physical and mental health of female patients.