Copyright B 2015 Wolters Kluwer Health, Inc. All rights reserved.
Yingzi Zhang, MS Kristine Kwekkeboom, PhD, RN Marcia Petrini, PhD, RN
Uncertainty, Self-efficacy, and Self-care Behavior in Patients With Breast Cancer Undergoing Chemotherapy in China K E Y
W O R D S
Background: Treatment for breast cancer causes uncertainty in the face of new and
Breast cancer
distressing experiences and often results in the need for self-care. Identifying how
Chemotherapy
uncertainty influences self-care behavior is essential to design interventions that enhance
Self-care behavior
self-care capacity and improve patient outcomes. Objectives: The aims of this
Self-efficacy
study were to describe the levels of uncertainty, self-efficacy, and self-care behavior in
Uncertainty
Chinese women receiving chemotherapy for breast cancer and to determine if self-efficacy mediates the relationship between uncertainty and self-care behavior. Methods: A cross-sectional descriptive correlational design was used. Ninety-seven participants completed the Generalized Self-efficacy Scale, the Mishel Uncertainty in Illness Scale, and the Appraisal of Self-care Agency ScaleYRevised. Descriptive statistics were used to analyze the levels of uncertainty, self-efficacy, and self-care behaviors in the sample. Multiple regression was used to test the mediating effect of self-efficacy in the relationship between uncertainty and self-care behavior. Results: Mean ratings of uncertainty (76.70), self-efficacy (27.15), and self-care behavior (53.96) all fell in the moderate range. Both uncertainty and self-efficacy independently predicted self-care behavior, explaining 18.2% of the variance, but self-efficacy did not mediate the relationship between uncertainty and self-care behavior. Conclusions: Research is needed to further evaluate the proposed relationships using instruments specific to/related to cancer and evaluate change over time. Self-care interventions that have been efficacious in Western populations could be revised to assist Chinese women to reduce uncertainty and enhance self-efficacy in coping with
Author Affiliations: School of Nursing, Wuhan University, Wuhan, Hubei, China (Ms Zhang and Dr Petrini); and School of Nursing, University of WisconsinMadison (Ms Zhang and Dr Kwekkeboom). This work was completed to fulfill the requirements of the master’s thesis and was supported by Wuhan University School of Nursing. The authors have no conflicts of interest to disclose.
Uncertainty, Self-efficacy and Self-care in Breast Cancer
Correspondence: Yingzi Zhang, MS, School of Nursing, University of Wisconsin-Madison, K6/117 Clinical Science Center, 600 Highland Ave, Madison, WI 53792 ([email protected]). Accepted for publication April 13, 2014. DOI: 10.1097/NCC.0000000000000165
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breast cancer. Implications for Practice: Self-care intervention programs should include strategies to reduce uncertainty and enhance self-efficacy in coping with breast cancer treatment. n
Literature Review
Breast cancer is the second most common cancer, with an estimated 1.67 million new cancer cases diagnosed in 2012 worldwide.1 The estimated annual incidence of breast cancer in Chinese women is 187 213, with an incidence rate of 15.1%.1 Chemotherapy is widely used in the treatment of breast cancer and causes many adverse effects, such as hair loss, vomiting, nausea, anorexia, fatigue, anxiety, and sleep disturbance.2,3 Women diagnosed with breast cancer are challenged to learn to manage these distressing adverse effects and also to participate in complex treatment regimens and cope with a life-threatening diagnosis. The breast cancer experience can cause significant psychological burden and put heavy self-care demands on these patients.4Y6 Self-care behavior has been defined as the range of voluntary activities that an individual uses to maintain life, health, and well-being. It is learned behavior and is performed by individuals on their own behalf.7 Some self-care behaviors may be intuitive, for example, resting when feeling fatigued. More complex and systematic self-care behaviors may be taught by nurses to help patients cope with the anticipated effects of chemotherapy treatment. Several studies have examined self-care interventions to improve coping in patients with breast cancer, demonstrating beneficial effects of strategies such as written materials about self-care skills,8 audiotapes of cognitive-behavioral coping techniques,6,9 and a self-help training program including uncertainty management.2 Two nurse investigators, Braden and Mishel, have developed frameworks and conducted a series of studies demonstrating the impact of uncertainty and the role of self-care behavior in coping with and adjusting to chronic illnesses, including cancer.10Y13 They postulated that disease and treatment adverse effects, when recognized as unfamiliar and in the absence of supportive structure, can lead to feelings of uncertainty.10 Mishel11 defined uncertainty as the inability to determine the meaning of events. She suggested that uncertainty occurs in situations where the decision maker is unable to assign definite values to objects and events or unable to accurately predict outcomes.11 In women with breast cancer undergoing treatment, lack of information about the disease, treatment, and expected adverse effects may contribute to high levels of uncertainty.10,14 Braden’s Self-help Model suggests that uncertainty may diminish resourcefulness and ultimately undermine self-care behavior.12,13 Indeed, studies document the relationship between uncertainty and self-care behavior and that interventions designed to reduce uncertainty lead to improvements in self-care.12,13 Neither Mishel’s Uncertainty in Illness theory nor Braden’s Self-help Model specifically addresses the concept of self-efficacy, although it is arguably a logical and useful concept in explicating the relationship between uncertainty and self-care. Wood and Bandura15 described self-efficacy as one’s capacity and confidence to carry out a task or behavior and theorized that such belief is a
powerful cognitive mediator of action.16 Gist and Mitchell17 describe uncertainty as an important component in the formation of self-efficacy beliefs. They describe uncertainty as a component in assessing task complexity, which provides an external informational cue that contributes to one’s estimate of his/her ability to perform the task.17 With high levels of uncertainty, patients may feel less confident to make accurate judgments, identify appropriate actions, and engage in coping behaviors.11,18 In previous research, uncertainty has been shown to negatively correlate with self-efficacy. For example, in pregnant women, uncertainty in the experience of pregnancy was negatively correlated with self-efficacy for responding to novel or difficult fetal health situations.19 Moreover, in a study of Taiwanese patients who had received percutaneous coronary intervention 3 to 6 months before, illness-related uncertainty was negatively correlated with selfefficacy for physical activity.20 Several studies have demonstrated a positive relationship between self-efficacy and self-care behavior across a range of chronic conditions. A positive correlation was found between self-efficacy and self-care activities in patients with hypertension,21 type 2 diabetes,22 arthritis,23 heart failure,24 and cancer.25 Only 1 study was located that tested the mediating role of self-efficacy in the relationship between uncertainty and selfcare behavior. Using baseline data from an intervention study of adults with chronic idiopathic pain, LeFort26 demonstrated that self-efficacy mediated the relationship between uncertainty and self-care. Patients with greater uncertainty about their pain condition reported less self-efficacy for pain control behaviors and fewer self-care activities.26 Although cancer was the focus in only a few of these studies, chronic illnesses like hypertension, diabetes, and heart failure bear similarities to cancer in that they are chronic and potentially life-limiting and all require significant patient involvement in long-term monitoring and management of the health condition and frequent adjustment to changing illness and treatment trajectories. However, more research is necessary to determine if self-efficacy indeed mediates the effect of uncertainty on self-care, particularly in patients with cancer. One study27 reported that uncertainty correlated with selfcare behavior in Chinese patients with coronary heart disease, and Wen28 demonstrated a correlation between self-efficacy and self-care behavior in Chinese patients with breast cancer undergoing adjuvant chemotherapy. Apart from these 2 studies, much of the research on uncertainty, self-efficacy, and self-care in women with breast cancer has been conducted in Western populations. It is likely that the experiences of Chinese women with breast cancer may be different from that of Western women related to factors such as sociodemographic and cultural differences, differences in healthcare systems, and differences in availability of supportive services. For example, most Chinese patients with cancer receive chemotherapy entirely as an inpatient, not outpatient, procedure. This practice may foster the belief that care is the responsibility of others (eg, family and healthcare professionals) and leave Chinese women largely unprepared for self-care when receiving chemotherapy.
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Cultural differences in self-efficacy have also been demonstrated, with Chinese samples, particularly women, reporting lower selfefficacy than either men or women in German and Spanish samples.29 In the presence of low self-efficacy, Chinese women may experience many unmet needs related to cancer management that result in poor quality of life30 and greater psychological distress.31 Thus, it is critical to evaluate self-efficacy and its relationships with uncertainty and self-care in Chinese women. The aims of this study were as follows: 1. To describe the levels of self-efficacy, uncertainty, and selfcare behaviors in Chinese women receiving chemotherapy for breast cancer. 2. To test the mediating effect of self-efficacy in the relationship between uncertainty and self-care behavior (Figure 1). We hypothesize that, after controlling for demographic and medical factors: 1. Uncertainty will be negatively correlated with self-care behavior. 2. Uncertainty will be negatively correlated with self-efficacy. 3. Self-efficacy will be positively correlated with self-care behavior, controlling for the effect of uncertainty. n
Methods
Design and Sample A cross-sectional descriptive correlational design was used. In the timeframe allotted for study completion, a convenience sample of 97 women receiving chemotherapy for a new diagnosis of breast cancer were recruited from 3 university-affiliated government hospitals in central south China. In China, persons with cancer are typically hospitalized for the course of chemotherapy. Participants had to be 1 month or more post mastectomy or lumpectomy, currently receiving inpatient chemotherapy (any cycle number in the initial course of treatment), and able to communicate verbally and read and write in Chinese. Women who were newly diagnosed with a recurrence of cancer, newly diagnosed with any disease other than breast cancer within the previous 3 months, and with terminal illness expected to cause death
within 1 year were excluded because these could substantially influence self-efficacy, uncertainty, and self-care behavior.
Instruments Demographic and medical information were collected directly from patients. Participants reported their age, family income, financial resources, educational level, marital status, employment status, religious beliefs, stage of cancer, type of treatment, chemotherapy cycle length, and comorbidities. Uncertainty was measured using the Mishel Uncertainty in Illness Scale for Adults (MUIS-A).32 The MUIS-A has 2 factors, which are ambiguity and complexity. The 16-item ambiguity subscale measures the perception that cues about the state of the illness are vague and indistinct and tend to blur and overlap. Twelve items on the complexity subscale measure the perception that cues about treatment and the system of care are multiple, intricate, and varied. Items are measured on 5-point Likert scales from 1 (strongly disagree) to 5 (strongly agree), with responses summed across all items to create the total scale score. The possible range of scores is 28 to 140, with higher scores indicating greater levels of uncertainty. In previous research, the Cronbach’s ! ranged from .90 to .94 for the total scale.32 The scale was translated into Chinese for this study. The first author (Y.Z.) translated the English scale to Chinese, it was then back translated into English by an English teacher, and the back-translated version was evaluated for consistency of meaning by the third author (M.P.). The translated version demonstrated good internal consistency reliability, with a total scale Cronbach’s ! of .87. Self-efficacy was measured using the Chinese version of the General Self-efficacy Scale (GSE).29 It consists of 10 items designed to assess beliefs about confidence in one’s personal ability to cope with a variety of difficult life situations. Items are rated on a 4-point scale with the anchors 1 (not at all true) to 4 (exactly true). The potential range of total scores is 10 to 40. Higher scores indicate greater levels of self-efficacy. The Chinese version of the GSE has demonstrated a Cronbach’s ! of .91 in previous research.29 In this study, a Cronbach’s ! of .82 was obtained. The Appraisal of Self-Care Agency ScaleYRevised (ASAS-R) scale was used to measure self-care.33 It is a 15-item scale that
Figure 1 n Conceptual framework.
Uncertainty, Self-efficacy and Self-care in Breast Cancer
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measures one’s general and specific capabilities to engage in selfcare (eg, I am able to get the information I need) as well as selfcare behaviors (eg, I have changed some of my old habits in order to improve my health). Items use a 5-point Likert type scale ranging from 1 (totally disagree) to 5 (totally agree), with summated scores ranging from 15 to 75 and higher scores indicating greater self-care. The scale was translated into Chinese for this study as described above for the MUIS-A. The overall ASAS-R had a Cronbach’s ! of .89 in previous research.33 The translated ASAS-R had a Cronbach’s ! of .75 in this study.
Procedure The study was approved by the ethics committees of Wuhan University and the 3 hospitals where patients were recruited. Patients who met the inclusion criteria were identified by a research nurse and invited to participate in the study. The research nurse explained the study purpose and informed patients that their participation was completely voluntary and they may withdraw from the study at any time. The consent form included a statement that the patients’ medical care would not be affected by their decision to participate or withdraw from the study. After obtaining informed consent, the research nurse explained the instructions for answering questions. Participants completed the questionnaires at the time of recruitment, while the women were hospitalized for chemotherapy. The research nurse was present to clarify any items that were confusing. Approximately 15 to 20 minutes was required to complete the questionnaires. No compensation was provided.
2. Determine if uncertainty is associated with self-efficacy (GSE) by regressing the GSE score on the MUIS-A score. 3. Determine if self-efficacy mediates the effect of uncertainty on self-care behavior by regressing the ASAS-R score on the MUIS-A and GSE scores, together. Mediation is present if the association between uncertainty and self-care behavior is either no longer statistically significant or reduced significantly. All regressions were conducted controlling for demographic and medical factors shown in previous research to be related to uncertainty, self-efficacy, and self-care. These variables included age, family income, financial resources, educational level, marital status, employment status, religious beliefs, stage of cancer, type
Table 1 & Demographic Characteristics and Medical Characteristics of the Sample (N = 97)
Characteristics
Category
n
%
Age, y
20Y40 40Y60 Q60 Illiterate Primary school Middle school High school College Without a partner Have a spouse or partner Unemployed Employed Themselves
7 75 15 5 7 26 41 18 7 90
7.2 77.3 15.5 5.2 7.2 26.8 42.3 18.6 7.2 92.8
Spouse Children G2000 2000Y4000 94000 None Buddhism Christian Folk beliefs I II III IV Chemotherapy Chemotherapy and radiation therapy 2 wk 3 wk 4 wk None Diabetes Hypertension Diabetes and hypertension Hypertension and heart disease
23 5 34 41 22 83 7 4 3 17 59 19 2 59 38
23.7 5.2 35.1 42.3 22.7 85.6 7.2 4.1 3.1 17.5 60.8 19.6 2.1 60.8 39.2
15 54 28 78 4 13 1
15.5 55.7 28.9 80.4 4.1 13.4 1.0
1
1.0
Educational level
Marital status
Employment
Data Analysis Data were screened for missing items. Only 7 items were found to be missing, and these were imputed using item-mean substitution across the sample. Total scale scores (not subscales) were computed for measures of self-efficacy, uncertainty, and self-care behavior, and all were analyzed as continuous variables. Descriptive statistics (eg, frequency, percentage, mean, and standard deviation) were computed to describe the demographic and medical characteristics of participants and their levels of self-efficacy, uncertainty, and self-care. Bivariate correlations among all study variables were computed for descriptive purposes. The Pearson correlation coefficient was used for continuous and interval variables (age, cycle length, stage of cancer, uncertainty, self-efficacy, and self-care) and Spearman > for ordinal and dichotomous categorical variables. Multiple regression was used to explore the mediating effect of self-efficacy in the relationship between uncertainty and selfcare. Regression assumptions of normality, homoscedasticity, and multicollinearity were tested by examining histograms and scatterplots of the standardized residuals, normal probability plots, and variance inflation factors. The assumptions were not violated and multicollinearity was not a problem. Mediation was tested using the procedure described by Baron and Kenny,34 which includes the following 3 steps.
Financial resource (who paid for healthcare)
Family income, Yuan/mo
Religious belief
Stage of cancer
Type of therapy
Chemotherapy cycle length
Comorbidity
1. Determine if uncertainty (MUIS-A) is associated with selfcare behavior (ASAS-R) by regressing the ASAS-R score on the MUIS-A score. E22 n Cancer NursingTM, Vol. 38, No. 3, 2015 Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
32 33.0 65 67.0 69 71.1
Zhang et al
1 1 0.283b 1 0.019 j0.314b
13 7
1 j0.077 j0.034 j0.076 0.003 j0.071 0.017 j0.163
8
9
10
Variable
Mean
SD
Obtained Range
!
28Y140 10Y40 15Y75
44Y115 10Y38 34Y69
.87 .82 .75
1 j0.211a j0.080 0.350b j0.222a j0.007 0.071 0.015 0.203a 0.143 0.367b j0.280b 0.035 0.232a
1 0.103 0.537b j0.340b 0.523b j0.099 j0.047 j0.155 j0.028 j0.069 j0.169 0.241a 0.218a
1 0.059 0.068 0.231a j0.096 0.224a 0.021 j0.014 j0.063 j0.026 0.046 0.125
1 j0.659b 0.479b j0.073 j0.021 j0.085 0.046 0.125 j0.175 0.207a 0.181
1 j0.318b j0.083 0.046 0.121 j0.026 j0.150 0.066 j0.237a j0.047
6 5 4 3
a
Uncertainty 76.70 13.550 Self-efficacy 27.15 5.672 Self-care behavior 53.96 6.076
Possible Range
Age Education Marital status Employment Financial resource Family income Religious beliefs Type of therapy Stage of cancer Cycle length Comorbidity Uncertainty Self-efficacy Self-care
Behavior Scores (N = 97)
1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14.
Table 2 & Self-efficacy, Uncertainty, Self-care
2
Mediation analysis was conducted as planned to test the specified hypotheses. Results are presented in Table 4 and Figure 2. In step 1, uncertainty was a significant predictor of self-care (" = j.192, P = .047). In step 2, the relationship between uncertainty and self-efficacy was not statistically significant (" = .205, P = .960). In step 3, both uncertainty (" = j.247, P = .015) and self-efficacy (" = .266, P = .006) independently predicted selfcare behavior. Because uncertainty was not significantly related to self-efficacy, and because self-efficacy did not reduce the effect of uncertainty on self-care behavior in the analysis, self-efficacy
1
Mediating Effect of Self-efficacy
Table 3 & Correlation Matrix of Research Variables (N = 97)
The levels of uncertainty, self-efficacy, and self-care behaviors in women receiving chemotherapy for breast cancer are presented in Table 2. Mean (SD) uncertainty was 76.70 (13.55) on a scale of 28 to 140, mean (SD) self-efficacy was 27.15 (5.67) on a scale of 10 to 40, and mean (SD) self-care was 53.96 (6.08) on a scale of 15 to 75. Bivariate correlations among study variables are reported in Table 3.
1 j0.201a j0.032 j0.050 j0.040 0.040 j0.321b 0.243a 0.292b
Levels of Uncertainty, Self-efficacy, and Self-care Behavior
P G .05. P G.01.
A total of 97 women agreed to participate in this study. Table 1 presents patients’ demographic and medical characteristics. All of the patients were women with children. The mean (SD) age was 51.76 (9.016) years. About half of them completed high school education (42.3%). Most of the women were married (92.8%) and employed (67%). For most (77.4%), their family income each month was below 4000 Yuan (US$658, €479). Most of the women (71.1%) financed their healthcare for themselves. Most (80.4%) had the diagnosis of stage II breast cancer without any comorbidity. All were receiving chemotherapy or chemotherapy with radiotherapy. For approximately half (55.7%), the chemotherapy cycle length was 3 weeks.
1 0.359b 1 j0.054 0.005 1 0.083 0.058 j0.115 0.294b 0.100 j0.079 j0.039 j0.065 0.073 j0.008 0.082 0.169
11
1 j0.247a 0.111 0.084
Characteristics of the Sample
Uncertainty, Self-efficacy and Self-care in Breast Cancer
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Results
12
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of treatment, chemotherapy cycle length, and comorbidities.10,35Y42 One-tailed tests were used to explore the hypothesized directional relationships among uncertainty, self-efficacy, and self-care. A threshold of significance for all tests was set at .05. All analyses were performed using SPSS 20.0 (IBM Inc, Armonk, New York).
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Table 4 & Mediating Effects of Self-efficacy With Covariates of Demographic and Medical Variables (N = 97) Model Summary
Model 1 Model 2 Model 3
Coefficients
R2
P
Independent
Dependent
0.225 0.189 0.283
.031 .099 .006
Uncertainty Uncertainty Uncertainty Self-efficacy
SCB Self-efficacy SCB
" j.086 .086 j.111 .285
SE
Standardized "
P
.051 .049 .050 .111
j.192 .205 j.247 .266
.047 .960 .015 .006
Abbreviation: SCB, self-care behavior.
did not mediate the effects of uncertainty on self-care behavior. The total variance explained by all variables combined was 28.3%. Excluding the effect of covariates, uncertainty and self-efficacy explained 18.2% of the variance in self-care.
n
Discussion
The current study found moderate levels of uncertainty, selfefficacy, and self-care among the Chinese women sampled. Observed responses reflected nearly the full range of possible scores, indicating an array of individual differences on all 3 variables. The average level of uncertainty in our sample (76.70) was higher than that reported in previous studies using the MUIS-A 28-item scale, which reported scores ranging from 63.76 to 65.30 in a sample of Western patients with breast cancer.42 Women in the current sample were recently diagnosed and had few comorbidities. They would be expected to have more uncertainty because they lack any experiential frame of reference to define illness-related events.43 In addition, the low educational level of the sample in this study may have contributed to greater uncertainty35; less than 20% of our sample had more than a high school education. Moreover, many of our participants (77.4%) had family income of less than 4000 Yuan per month (US$658, €479), which is far below the average medical expense for inpatients in third-level hospitals (10 442.4 Yuan in 2010).44 Families spend almost 50% of their household income for healthcare expenses when a family member has cancer.45 The economic pressure combined with complex cancer treatment and limited illness experience and education may have led to greater feelings of uncertainty in this sample. The mean score for perceived self-efficacy found in this study (27.15) was similar to or slightly lower than those reported by other investigators, ranging from 27.4 to 31.91 for Western patients with cancer37,46,47 and 29.63 for Chinese women with breast cancer.48 Participants in the current sample were relatively young and most did not have a college education, factors that correlated with lower self-efficacy in previous studies.37,38 According to Bandura,49 past mastery experiences are an important resource in promoting self-efficacy beliefs, and patients who are young and without any disease history may be less confident in their coping ability. The level of self-care behavior reported in the current sample (53.96) is consistent with a previous study reporting a mean selfcare behavior score of 54.5 in the general population.33 We had expected to observe higher levels of self-care relative to the general
population given that the study participants were currently receiving chemotherapy and experiencing its adverse effects. It is possible that women were unaware of self-care strategies to cope with chemotherapy-related challenges or symptoms. It may also have been that others were providing care for these women at the time of assessment. Unlike most Western countries where chemotherapy is administered on an outpatient basis, these Chinese patients were hospitalized for the duration of their chemotherapy cycles. Being hospitalized may have resulted in less of a demand for self-care, as hospital staff and family members were present to provide assistance and support for the women with breast cancer. Other potential explanations may be related to the measure of self-care used in this study. The ASAS-R is a measure of general, not cancerspecific, self-care. Engagement in typical daily self-care may not have changed, while other less common (cancer-specific) self-care needs may have been considerably different. In addition, the ASAS-R items measure both actual self-care behavior and capacity to engage in self-care behavior. Participants may have reported low scores on capacity items while hospitalized and receiving chemotherapy. Evidence in this study partially supported our research hypotheses. We demonstrated that uncertainty was negatively correlated with self-care behavior, suggesting that the higher the level of uncertainty that patients feel, the less self-care they perform to cope with effects of the disease.12 Patients without sufficient information or knowledge cannot interpret illness situations easily and are restricted in presenting satisfying and appropriate self-care behavior when the breast cancer or its treatment is perceived as complex and difficult to predict. Therefore, providing uncertainty management is an essential component in self-care interventions for patients with breast cancer.9
Figure 2 n Observed relationships. *P G .05; **P G .01.
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Our study also demonstrated that self-efficacy was positively correlated with self-care behavior, controlling for the effect of uncertainty. This finding is consistent with Bandura’s Selfefficacy theory,50 which indicates that individuals need to believe that they can put self-care activities into practice to exert sufficient effort and be able to perform self-care behavior. In other words, their self-efficacy facilitates the achievement of self-care goals and adaptation to illness.36 Thus, a second essential component of self-care interventions is strategies to enhance patients’ confidence and ability to engage in self-care activities. Not all of the research hypotheses were supported by the data. We hypothesized a negative relationship between uncertainty and self-efficacy, with greater levels of uncertainty eroding one’s confidence for coping with the challenge. Conversely, we found a positive relationship between uncertainty and self-efficacy, although not statistically significant. The direction of the relationship suggests that patients with higher levels of illness uncertainty tended to report greater confidence in their ability to manage difficult life situations. A similar relationship was demonstrated in spouse’s psychological adaptation to wives’ breast cancer diagnosis. Spouses who reported more uncertainty had greater confidence to emotionally support their wives and manage the impact of breast cancer.51 Although the sources of uncertainty and personal impact of cancer are different between women with breast cancer and their spouses, both may share a similar spirit of ‘‘rising to the challenge’’ and being positive and hopeful in the face of a lifethreatening diagnosis. How people with cancer appraise an uncertain situation is continually fluctuating. Future longitudinal evaluation may be useful to detect changes in uncertainty over time and how uncertainty influences self-efficacy at different points in the breast cancer trajectory. The mediating role of self-efficacy in the relationship between uncertainty and self-care behavior was also not supported. One explanation may be the selection of a generalized self-efficacy scale, rather than a cancer-specific self-efficacy scale. The GSE measures global confidence in one’s coping ability across all stressful situations, which may be perceived as a trait-like variable in this study. Illness uncertainty occurs when a specific cancer-related situation is complex, ambiguous, and unpredictable or when the patient lacks information about a specific cancer stressor, which is a more state-like variable.12 It is presumed that illness (cancerrelated) self-efficacy may be a stronger mediator of the relationship between uncertainty and self-care and that cancer-related self-efficacy may also be negatively rather than positively correlated with illness uncertainty. There are some limitations of this study that need to be taken into consideration. First, the results of this study were obtained from a convenience sample of women who all received chemotherapy during an inpatient stay at a university-affiliated hospital. They may not be representative of all Chinese women with breast cancer, particularly those who cannot access or afford third-level hospital care. Second, the study was cross-sectional and cannot account for temporal order of effects. In the current analysis, we cannot be sure that uncertainty and self-efficacy led to specific self-care activity. It is possible that successful self-care behaviors reduced uncertainty or improved one’s self-efficacy. Third, neither the self-efficacy nor the self-care measure was illness
Uncertainty, Self-efficacy and Self-care in Breast Cancer
(cancer) specific, which may have weakened our ability to detect mediation in this sample. Moreover, the self-care measure included items that measured both actual behavior and perceived behavioral ability. Fourth, the instruments used in the study were developed in the Western culture, and although all had good reliability, some (MUIS and ASAS-R) have not been validated for use with a Chinese mainland population. Fifth, an a priori power analysis was not done to determine sample size. Post hoc analysis indicated a power of 0.52 to 0.75 for observed relationships. However, we do not know if these observed effect sizes accurately estimate the true population effect sizes. Our sample of 97 participants is sufficient if the true effect sizes of the mediation pathways are large (> = 0.50, N = 26) or medium (> = 0.30, N = 82), but a larger sample size would be needed if the true effect sizes are small (> = 0.10, N = 779). Finally, we did not collect information about the exact length of time since diagnosis or chemotherapy cycle number. Observed responses may have been influenced by how ‘‘new’’ chemotherapy was to the patient (ie, how much treatment women had already had), although previous studies have demonstrated consistently greater uncertainty levels during the treatment period compared with posttreatment.3
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Conclusion
Despite the limitations, the findings suggest some potential implications for clinical practice. Our results underscore the important roles that uncertainty and self-efficacy play in self-care behavior. Health professionals need to assess patients’ knowledge and information needs when facing a new cancer diagnosis and new treatment regimens with expected adverse effects. Nurses can help patients manage uncertainty by providing education and assisting patients to anticipate and correctly make sense of cancerrelated experiences. Nurses also need to build or restore patients’ confidence in their ability to successfully cope with these new challenges and help them to actively engage in self-care tasks. Intervention programs for women with breast cancer should emphasize tailored ways to reduce uncertainty and enhance perceptions of self-efficacy and controllability of unfamiliar experiences. Some uncertainty and self-efficacy interventions have demonstrated efficacy in Western samples of patients with cancer. Given the disparities in culture and economic status, these interventions could be revised and tested to meet the unique needs of Chinese women with breast cancer. ACKNOWLEDGMENTS
The authors express their appreciation to Ms Xiaoxing Wen for her assistance in back-translation of study questionnaires and to the patients and nursing staff in the Department of Oncology of the 3 hospitals for identifying participants in the process of data collection. The authors thank the Kwekkeboom research group for feedback on earlier versions of the manuscript.
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[Internet]. Lyon, France: International Agency for Research on Cancer; 2010. http://globocan.iarc.fr/Pages/fact_sheets_cancer.aspx. Accessed December 16, 2013. Badger T, Braden C, Mishel M. Depression burden, self-help interventions, and side effect experience in women receiving treatment for breast cancer. Oncol Nurs Forum. 2001;28(3):567Y574. Kim SH, Lee R, Lee KS. Symptoms and uncertainty in breast cancer survivors in Korea: differences by treatment trajectory. J Clin Nurs. 2012;21:1014Y1023. Dodd MJ. Self-care for patients with breast cancer to prevent side effects of chemotherapy: a concern for public health nursing. Public Health Nurs. 1984;1(4):202Y209. Badger TA, Braden CJ, Mishel MH, Longman A. Depression burden, psychological adjustment, and quality of life in women with breast cancer: patterns over time. Res Nurs Health. 2004;27(1):19Y28. Williams S, Schreier A. The effect of education in managing side effects in women receiving chemotherapy for treatment of breast cancer. Oncol Nurs Forum. 2004;31(1):E16YE23. Orem DE. Nursing: Concepts of Practice. St Louis, MO: Mosby; 1995. Craddock RB, Adams PF, Usui WM, Mitchell L. An intervention to increase use and effectiveness of self-care measures for breast cancer chemotherapy patients. Cancer Nurs. 1999;22(4):312Y319. Gil KM, Mishel MH, Belyea M, Germino B, Porter LS, Clayton M. Benefits of the uncertainty management intervention for African American and white older breast cancer survivors: 20-month outcomes. Int J Behav Med. 2006; 13(4):286Y294. Mishel MH, Braden CJ. Finding meaning: antecedents of uncertainty in illness. Nurs Res. 1998;37(2):98Y103. Mishel MH. Perceived uncertainty and stress in illness. Res Nurs Health. 1984;7(3):163Y171. Braden C, Mishel M, Longman A. Self-help Intervention Project: women receiving breast cancer treatment. Cancer Pract. 1998;6(2):87Y98. Kreulen GJ, Braden CJ. Model test of the relationship between self-helppromoting nursing interventions and self-care and health status outcomes. Res Nurs Health. 2004;27(2):97Y109. Lien CY, Chen SH, Tsai PP, Chen KM, Heish YI, Liang Y. Effectiveness of nursing instruction in reducing uncertainty, anxiety and self-care in breast cancer women undergoing initial chemotherapy. J Nurs. 2010;57(6):51Y60. Wood R, Bandura A. Impact of conceptions of ability on self-regulatory mechanisms and complex decision making. J Pers Soc Psychol. 1989;56(3): 407Y415. Bandura A. Self-efficacy: The Exercise of Control. New York, NY: WH Freeman; 1997. Gist ME, Mitchell TR. Self-efficacy: a theoretical analysis of its determinants and malleability. Acad Manag Rev. 1992;17(2):183Y211. Wonghongkul T, Moore SM, Musil C, Schneider S, Deimling G. The influence of uncertainty in illness, stress appraisal, and hope on coping in survivors of breast cancer. Cancer Nurs. 2000;23(6):422Y429. Hui Choi WH, Lee GL, Chan CHY, Cheung RYH, Lee ILY, Chan CLW. The relationships of social support, uncertainty, self-efficacy, and commitment to prenatal psychosocial adaptation. J Adv Nurs. 2012;68(12):2633Y2645. Huang CH, Ho MY, Tsai CR. A study of physical activity, uncertainty and health self-efficacy in the patients after percutaneous coronary intervention. Tzu Chi Nurs J. 2012;11(3):66Y76. Warren-Findlow J, Seymour RB, Brunner Huber LR. The association between self-efficacy and hypertension self-care activities among African American adults. J Community Health. 2012;37(1):15Y24. Sharoni SKA, Wu SFV. Self-efficacy and self-care behavior of Malaysian patients with type 2 diabetes: a cross sectional survey. Nurs Health Sci. 2012;14(1):38Y45. Yoo H, Kim CJ, Jang Y, You M. Self-efficacy is associated with selfmanagement behaviours and health status of South Koreans with chronic diseases. Int J Nurs Pract. 2011;17(6):599Y606. Dickson VV, Buck H, Riegel B. Multiple comorbid conditions challenge heart failure self-care by decreasing self-efficacy. Nurs Res. 2013;62(1):2Y9. Lev EL. Bandura’s theory of self-efficacy: applications to oncology. Sch Inq Nurs Pract. 1997;11(1):21Y49. LeFort SM. A test of Braden’s self-help model in adults with chronic pain. J Nurs Sch. 2000;32(2):153Y160.
27. Chen SN, Deng T, Sun M. Analysis on correlation between coronary heart disease uncertainty and self-care compliance. Chin Nurs Res. 2012;26(34): 3283Y3284. 28. Wen H. Self-efficacy, Self-care Agency and Depression in Breast Cancer Patients Undergoing Adjuvant Chemotherapy [master thesis]. Guangzhou, China: Sun Yat-Sen University; 2007. 29. Schwarzer R, Ba¨Qler J, Kwiatek P, Schro¨der K, Zhang JX. The assessment of optimistic self-beliefs: comparison of the German, Spanish, and Chinese versions of the General Self-efficacy Scale. Appl Psychol. 1997;46(1):69Y88. 30. Yeung NCY, Lu Q. Affect as a mediator between self-efficacy and quality of life among Chinese cancer survivors in China. Eur J Cancer Care. 2014;23(1): 149Y155. 31. Wu A, Tang C, Kwok T. Self-efficacy, health locus of control, and psychological distress in elderly Chinese women with chronic illnesses. Aging Mental Health. 2004;8(1):21Y28. 32. Mishel MH. Uncertainty in Illness Scales Manual. Chapel Hill, NC: University of North Carolina-Chapel Hill; 1997. 33. Sousa VD, Zauszniewski JA, Bergquist-Beringer S, Musil CM, Neese JB, Jaber AF. Reliability, validity and factor structure of the Appraisal of SelfCare Agency ScaleYRevised (ASAS-R). J Eval Clin Pract. 2010;16(6):1031Y1040. 34. Baron RM, Kenny DA. The moderator-mediator variable distinction in social psychological research: conceptual, strategic, and statistical considerations. J Pers Soc Psychol. 1986;51(6):1173Y1182. 35. Clayton MF, Mishel MH, Belyea M. Testing a model of symptoms, communication, uncertainty, and well-being, in older breast cancer survivors. Res Nurs Health. 2006;29(1):18Y39. 36. Akin S, Can G, Durna Z, Aydiner A. The quality of life and self-efficacy of Turkish breast cancer patients undergoing chemotherapy. Eur J Oncol Nurs. 2008;12(5):449Y456. 37. Rottmann N, Dalton SO, Christensen J, Frederiksen K, Johansen C. Selfefficacy, adjustment style and well-being in breast cancer patients: a longitudinal study. Qual Life Res. 2010;19(6):827Y836. 38. Howsepian BA, Merluzzi TV. Religious beliefs, social support, self-efficacy and adjustment to cancer. Psychooncology. 2009;18(10):1069Y1079. 39. Diep ND. Self-care in Women With Breast Cancer [master thesis]. Tucson, AZ: University of Arizona; 1992. 40. Norris R, Liu Q, Bauer-Wu S. Age and functional ability are associated with self-care practices used by women with metastatic breast cancer: an exploratory study. J Nurs Healthcare Chronic Illn. 2009;1(1):71Y77. 41. Seegers C, Walker B, Nail L, Schwartz A, Mudgett L, Stephen S. Self-care and breast cancer recovery. Cancer Pract. 1998;6(6):339Y345. 42. Wong CA, Bramwell L. Uncertainty and anxiety after mastectomy for breast cancer. Cancer Nurs. 1992;15(5):363Y371. 43. Mishel MH. The measurement of uncertainty in illness. Nurs Res. 1981; 30(5):258Y263. 44. National Health and Family Planning Commission of the People’s Republic of China. China Health Statistics, 2012 (2012 ). http:// www.moh.gov.cn/mohwsbwstjxxzx/s7967/201206/55044.shtml. Published June 6, 2012. Accessed July 1, 2013. 45. Li Y, Wu Q, Xu L, et al. Factors affecting catastrophic health expenditure and impoverishment from medical expenses in China: policy implications of universal health insurance. Bull World Health Organ. 2012;90(9):664Y671. 46. Kreitler S, Peleg D, Ehrenfeld M. Stress, self-efficacy and quality of life in cancer patients. Psychooncology. 2007;16(4):329Y341. 47. Melchior H, Bu¨scher C, Thorenz A, Grochocka A, Koch U, Watzke B. Self-efficacy and fear of cancer progression during the year following diagnosis of breast cancer. Psychooncology. 2013;22(1):39Y45. 48. Lam WWT, Fielding R. Is self-efficacy a predictor of short-term post-surgical adjustment among Chinese women with breast cancer? Psychooncology. 2007; 16(7):651Y659. 49. Bandura A. Self-efficacy: toward a unifying theory of behavioral change. Psychol Rev. 1977;84(2):191Y215. 50. Bandura A. Regulation of cognitive processes through perceived self-efficacy. Dev Psychol. 1989;25(5):729Y735. 51. Lewis FM, Fletcher KA, Cochrane BB, Fann JR. Predictors of depressed mood in spouses of women with breast cancer. J Clin Oncol. 2008;26(8): 1289Y1295.
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Zhang et al
Yingzi Zhang, MS Kristine Kwekkeboom, PhD, RN Marcia Petrini, PhD, RN
Uncertainty, Self-efficacy, and Self-care Behavior in Patients With Breast Cancer Undergoing Chemotherapy in China K E Y
W O R D S
Background: Treatment for breast cancer causes uncertainty in the face of new and
Breast cancer
distressing experiences and often results in the need for self-care. Identifying how
Chemotherapy
uncertainty influences self-care behavior is essential to design interventions that enhance
Self-care behavior
self-care capacity and improve patient outcomes. Objectives: The aims of this
Self-efficacy
study were to describe the levels of uncertainty, self-efficacy, and self-care behavior in
Uncertainty
Chinese women receiving chemotherapy for breast cancer and to determine if self-efficacy mediates the relationship between uncertainty and self-care behavior. Methods: A cross-sectional descriptive correlational design was used. Ninety-seven participants completed the Generalized Self-efficacy Scale, the Mishel Uncertainty in Illness Scale, and the Appraisal of Self-care Agency ScaleYRevised. Descriptive statistics were used to analyze the levels of uncertainty, self-efficacy, and self-care behaviors in the sample. Multiple regression was used to test the mediating effect of self-efficacy in the relationship between uncertainty and self-care behavior. Results: Mean ratings of uncertainty (76.70), self-efficacy (27.15), and self-care behavior (53.96) all fell in the moderate range. Both uncertainty and self-efficacy independently predicted self-care behavior, explaining 18.2% of the variance, but self-efficacy did not mediate the relationship between uncertainty and self-care behavior. Conclusions: Research is needed to further evaluate the proposed relationships using instruments specific to/related to cancer and evaluate change over time. Self-care interventions that have been efficacious in Western populations could be revised to assist Chinese women to reduce uncertainty and enhance self-efficacy in coping with
Author Affiliations: School of Nursing, Wuhan University, Wuhan, Hubei, China (Ms Zhang and Dr Petrini); and School of Nursing, University of WisconsinMadison (Ms Zhang and Dr Kwekkeboom). This work was completed to fulfill the requirements of the master’s thesis and was supported by Wuhan University School of Nursing. The authors have no conflicts of interest to disclose.
Uncertainty, Self-efficacy and Self-care in Breast Cancer
Correspondence: Yingzi Zhang, MS, School of Nursing, University of Wisconsin-Madison, K6/117 Clinical Science Center, 600 Highland Ave, Madison, WI 53792 ([email protected]). Accepted for publication April 13, 2014. DOI: 10.1097/NCC.0000000000000165
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breast cancer. Implications for Practice: Self-care intervention programs should include strategies to reduce uncertainty and enhance self-efficacy in coping with breast cancer treatment. n
Literature Review
Breast cancer is the second most common cancer, with an estimated 1.67 million new cancer cases diagnosed in 2012 worldwide.1 The estimated annual incidence of breast cancer in Chinese women is 187 213, with an incidence rate of 15.1%.1 Chemotherapy is widely used in the treatment of breast cancer and causes many adverse effects, such as hair loss, vomiting, nausea, anorexia, fatigue, anxiety, and sleep disturbance.2,3 Women diagnosed with breast cancer are challenged to learn to manage these distressing adverse effects and also to participate in complex treatment regimens and cope with a life-threatening diagnosis. The breast cancer experience can cause significant psychological burden and put heavy self-care demands on these patients.4Y6 Self-care behavior has been defined as the range of voluntary activities that an individual uses to maintain life, health, and well-being. It is learned behavior and is performed by individuals on their own behalf.7 Some self-care behaviors may be intuitive, for example, resting when feeling fatigued. More complex and systematic self-care behaviors may be taught by nurses to help patients cope with the anticipated effects of chemotherapy treatment. Several studies have examined self-care interventions to improve coping in patients with breast cancer, demonstrating beneficial effects of strategies such as written materials about self-care skills,8 audiotapes of cognitive-behavioral coping techniques,6,9 and a self-help training program including uncertainty management.2 Two nurse investigators, Braden and Mishel, have developed frameworks and conducted a series of studies demonstrating the impact of uncertainty and the role of self-care behavior in coping with and adjusting to chronic illnesses, including cancer.10Y13 They postulated that disease and treatment adverse effects, when recognized as unfamiliar and in the absence of supportive structure, can lead to feelings of uncertainty.10 Mishel11 defined uncertainty as the inability to determine the meaning of events. She suggested that uncertainty occurs in situations where the decision maker is unable to assign definite values to objects and events or unable to accurately predict outcomes.11 In women with breast cancer undergoing treatment, lack of information about the disease, treatment, and expected adverse effects may contribute to high levels of uncertainty.10,14 Braden’s Self-help Model suggests that uncertainty may diminish resourcefulness and ultimately undermine self-care behavior.12,13 Indeed, studies document the relationship between uncertainty and self-care behavior and that interventions designed to reduce uncertainty lead to improvements in self-care.12,13 Neither Mishel’s Uncertainty in Illness theory nor Braden’s Self-help Model specifically addresses the concept of self-efficacy, although it is arguably a logical and useful concept in explicating the relationship between uncertainty and self-care. Wood and Bandura15 described self-efficacy as one’s capacity and confidence to carry out a task or behavior and theorized that such belief is a
powerful cognitive mediator of action.16 Gist and Mitchell17 describe uncertainty as an important component in the formation of self-efficacy beliefs. They describe uncertainty as a component in assessing task complexity, which provides an external informational cue that contributes to one’s estimate of his/her ability to perform the task.17 With high levels of uncertainty, patients may feel less confident to make accurate judgments, identify appropriate actions, and engage in coping behaviors.11,18 In previous research, uncertainty has been shown to negatively correlate with self-efficacy. For example, in pregnant women, uncertainty in the experience of pregnancy was negatively correlated with self-efficacy for responding to novel or difficult fetal health situations.19 Moreover, in a study of Taiwanese patients who had received percutaneous coronary intervention 3 to 6 months before, illness-related uncertainty was negatively correlated with selfefficacy for physical activity.20 Several studies have demonstrated a positive relationship between self-efficacy and self-care behavior across a range of chronic conditions. A positive correlation was found between self-efficacy and self-care activities in patients with hypertension,21 type 2 diabetes,22 arthritis,23 heart failure,24 and cancer.25 Only 1 study was located that tested the mediating role of self-efficacy in the relationship between uncertainty and selfcare behavior. Using baseline data from an intervention study of adults with chronic idiopathic pain, LeFort26 demonstrated that self-efficacy mediated the relationship between uncertainty and self-care. Patients with greater uncertainty about their pain condition reported less self-efficacy for pain control behaviors and fewer self-care activities.26 Although cancer was the focus in only a few of these studies, chronic illnesses like hypertension, diabetes, and heart failure bear similarities to cancer in that they are chronic and potentially life-limiting and all require significant patient involvement in long-term monitoring and management of the health condition and frequent adjustment to changing illness and treatment trajectories. However, more research is necessary to determine if self-efficacy indeed mediates the effect of uncertainty on self-care, particularly in patients with cancer. One study27 reported that uncertainty correlated with selfcare behavior in Chinese patients with coronary heart disease, and Wen28 demonstrated a correlation between self-efficacy and self-care behavior in Chinese patients with breast cancer undergoing adjuvant chemotherapy. Apart from these 2 studies, much of the research on uncertainty, self-efficacy, and self-care in women with breast cancer has been conducted in Western populations. It is likely that the experiences of Chinese women with breast cancer may be different from that of Western women related to factors such as sociodemographic and cultural differences, differences in healthcare systems, and differences in availability of supportive services. For example, most Chinese patients with cancer receive chemotherapy entirely as an inpatient, not outpatient, procedure. This practice may foster the belief that care is the responsibility of others (eg, family and healthcare professionals) and leave Chinese women largely unprepared for self-care when receiving chemotherapy.
E20 n Cancer NursingTM, Vol. 38, No. 3, 2015 Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
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Cultural differences in self-efficacy have also been demonstrated, with Chinese samples, particularly women, reporting lower selfefficacy than either men or women in German and Spanish samples.29 In the presence of low self-efficacy, Chinese women may experience many unmet needs related to cancer management that result in poor quality of life30 and greater psychological distress.31 Thus, it is critical to evaluate self-efficacy and its relationships with uncertainty and self-care in Chinese women. The aims of this study were as follows: 1. To describe the levels of self-efficacy, uncertainty, and selfcare behaviors in Chinese women receiving chemotherapy for breast cancer. 2. To test the mediating effect of self-efficacy in the relationship between uncertainty and self-care behavior (Figure 1). We hypothesize that, after controlling for demographic and medical factors: 1. Uncertainty will be negatively correlated with self-care behavior. 2. Uncertainty will be negatively correlated with self-efficacy. 3. Self-efficacy will be positively correlated with self-care behavior, controlling for the effect of uncertainty. n
Methods
Design and Sample A cross-sectional descriptive correlational design was used. In the timeframe allotted for study completion, a convenience sample of 97 women receiving chemotherapy for a new diagnosis of breast cancer were recruited from 3 university-affiliated government hospitals in central south China. In China, persons with cancer are typically hospitalized for the course of chemotherapy. Participants had to be 1 month or more post mastectomy or lumpectomy, currently receiving inpatient chemotherapy (any cycle number in the initial course of treatment), and able to communicate verbally and read and write in Chinese. Women who were newly diagnosed with a recurrence of cancer, newly diagnosed with any disease other than breast cancer within the previous 3 months, and with terminal illness expected to cause death
within 1 year were excluded because these could substantially influence self-efficacy, uncertainty, and self-care behavior.
Instruments Demographic and medical information were collected directly from patients. Participants reported their age, family income, financial resources, educational level, marital status, employment status, religious beliefs, stage of cancer, type of treatment, chemotherapy cycle length, and comorbidities. Uncertainty was measured using the Mishel Uncertainty in Illness Scale for Adults (MUIS-A).32 The MUIS-A has 2 factors, which are ambiguity and complexity. The 16-item ambiguity subscale measures the perception that cues about the state of the illness are vague and indistinct and tend to blur and overlap. Twelve items on the complexity subscale measure the perception that cues about treatment and the system of care are multiple, intricate, and varied. Items are measured on 5-point Likert scales from 1 (strongly disagree) to 5 (strongly agree), with responses summed across all items to create the total scale score. The possible range of scores is 28 to 140, with higher scores indicating greater levels of uncertainty. In previous research, the Cronbach’s ! ranged from .90 to .94 for the total scale.32 The scale was translated into Chinese for this study. The first author (Y.Z.) translated the English scale to Chinese, it was then back translated into English by an English teacher, and the back-translated version was evaluated for consistency of meaning by the third author (M.P.). The translated version demonstrated good internal consistency reliability, with a total scale Cronbach’s ! of .87. Self-efficacy was measured using the Chinese version of the General Self-efficacy Scale (GSE).29 It consists of 10 items designed to assess beliefs about confidence in one’s personal ability to cope with a variety of difficult life situations. Items are rated on a 4-point scale with the anchors 1 (not at all true) to 4 (exactly true). The potential range of total scores is 10 to 40. Higher scores indicate greater levels of self-efficacy. The Chinese version of the GSE has demonstrated a Cronbach’s ! of .91 in previous research.29 In this study, a Cronbach’s ! of .82 was obtained. The Appraisal of Self-Care Agency ScaleYRevised (ASAS-R) scale was used to measure self-care.33 It is a 15-item scale that
Figure 1 n Conceptual framework.
Uncertainty, Self-efficacy and Self-care in Breast Cancer
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measures one’s general and specific capabilities to engage in selfcare (eg, I am able to get the information I need) as well as selfcare behaviors (eg, I have changed some of my old habits in order to improve my health). Items use a 5-point Likert type scale ranging from 1 (totally disagree) to 5 (totally agree), with summated scores ranging from 15 to 75 and higher scores indicating greater self-care. The scale was translated into Chinese for this study as described above for the MUIS-A. The overall ASAS-R had a Cronbach’s ! of .89 in previous research.33 The translated ASAS-R had a Cronbach’s ! of .75 in this study.
Procedure The study was approved by the ethics committees of Wuhan University and the 3 hospitals where patients were recruited. Patients who met the inclusion criteria were identified by a research nurse and invited to participate in the study. The research nurse explained the study purpose and informed patients that their participation was completely voluntary and they may withdraw from the study at any time. The consent form included a statement that the patients’ medical care would not be affected by their decision to participate or withdraw from the study. After obtaining informed consent, the research nurse explained the instructions for answering questions. Participants completed the questionnaires at the time of recruitment, while the women were hospitalized for chemotherapy. The research nurse was present to clarify any items that were confusing. Approximately 15 to 20 minutes was required to complete the questionnaires. No compensation was provided.
2. Determine if uncertainty is associated with self-efficacy (GSE) by regressing the GSE score on the MUIS-A score. 3. Determine if self-efficacy mediates the effect of uncertainty on self-care behavior by regressing the ASAS-R score on the MUIS-A and GSE scores, together. Mediation is present if the association between uncertainty and self-care behavior is either no longer statistically significant or reduced significantly. All regressions were conducted controlling for demographic and medical factors shown in previous research to be related to uncertainty, self-efficacy, and self-care. These variables included age, family income, financial resources, educational level, marital status, employment status, religious beliefs, stage of cancer, type
Table 1 & Demographic Characteristics and Medical Characteristics of the Sample (N = 97)
Characteristics
Category
n
%
Age, y
20Y40 40Y60 Q60 Illiterate Primary school Middle school High school College Without a partner Have a spouse or partner Unemployed Employed Themselves
7 75 15 5 7 26 41 18 7 90
7.2 77.3 15.5 5.2 7.2 26.8 42.3 18.6 7.2 92.8
Spouse Children G2000 2000Y4000 94000 None Buddhism Christian Folk beliefs I II III IV Chemotherapy Chemotherapy and radiation therapy 2 wk 3 wk 4 wk None Diabetes Hypertension Diabetes and hypertension Hypertension and heart disease
23 5 34 41 22 83 7 4 3 17 59 19 2 59 38
23.7 5.2 35.1 42.3 22.7 85.6 7.2 4.1 3.1 17.5 60.8 19.6 2.1 60.8 39.2
15 54 28 78 4 13 1
15.5 55.7 28.9 80.4 4.1 13.4 1.0
1
1.0
Educational level
Marital status
Employment
Data Analysis Data were screened for missing items. Only 7 items were found to be missing, and these were imputed using item-mean substitution across the sample. Total scale scores (not subscales) were computed for measures of self-efficacy, uncertainty, and self-care behavior, and all were analyzed as continuous variables. Descriptive statistics (eg, frequency, percentage, mean, and standard deviation) were computed to describe the demographic and medical characteristics of participants and their levels of self-efficacy, uncertainty, and self-care. Bivariate correlations among all study variables were computed for descriptive purposes. The Pearson correlation coefficient was used for continuous and interval variables (age, cycle length, stage of cancer, uncertainty, self-efficacy, and self-care) and Spearman > for ordinal and dichotomous categorical variables. Multiple regression was used to explore the mediating effect of self-efficacy in the relationship between uncertainty and selfcare. Regression assumptions of normality, homoscedasticity, and multicollinearity were tested by examining histograms and scatterplots of the standardized residuals, normal probability plots, and variance inflation factors. The assumptions were not violated and multicollinearity was not a problem. Mediation was tested using the procedure described by Baron and Kenny,34 which includes the following 3 steps.
Financial resource (who paid for healthcare)
Family income, Yuan/mo
Religious belief
Stage of cancer
Type of therapy
Chemotherapy cycle length
Comorbidity
1. Determine if uncertainty (MUIS-A) is associated with selfcare behavior (ASAS-R) by regressing the ASAS-R score on the MUIS-A score. E22 n Cancer NursingTM, Vol. 38, No. 3, 2015 Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
32 33.0 65 67.0 69 71.1
Zhang et al
1 1 0.283b 1 0.019 j0.314b
13 7
1 j0.077 j0.034 j0.076 0.003 j0.071 0.017 j0.163
8
9
10
Variable
Mean
SD
Obtained Range
!
28Y140 10Y40 15Y75
44Y115 10Y38 34Y69
.87 .82 .75
1 j0.211a j0.080 0.350b j0.222a j0.007 0.071 0.015 0.203a 0.143 0.367b j0.280b 0.035 0.232a
1 0.103 0.537b j0.340b 0.523b j0.099 j0.047 j0.155 j0.028 j0.069 j0.169 0.241a 0.218a
1 0.059 0.068 0.231a j0.096 0.224a 0.021 j0.014 j0.063 j0.026 0.046 0.125
1 j0.659b 0.479b j0.073 j0.021 j0.085 0.046 0.125 j0.175 0.207a 0.181
1 j0.318b j0.083 0.046 0.121 j0.026 j0.150 0.066 j0.237a j0.047
6 5 4 3
a
Uncertainty 76.70 13.550 Self-efficacy 27.15 5.672 Self-care behavior 53.96 6.076
Possible Range
Age Education Marital status Employment Financial resource Family income Religious beliefs Type of therapy Stage of cancer Cycle length Comorbidity Uncertainty Self-efficacy Self-care
Behavior Scores (N = 97)
1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14.
Table 2 & Self-efficacy, Uncertainty, Self-care
2
Mediation analysis was conducted as planned to test the specified hypotheses. Results are presented in Table 4 and Figure 2. In step 1, uncertainty was a significant predictor of self-care (" = j.192, P = .047). In step 2, the relationship between uncertainty and self-efficacy was not statistically significant (" = .205, P = .960). In step 3, both uncertainty (" = j.247, P = .015) and self-efficacy (" = .266, P = .006) independently predicted selfcare behavior. Because uncertainty was not significantly related to self-efficacy, and because self-efficacy did not reduce the effect of uncertainty on self-care behavior in the analysis, self-efficacy
1
Mediating Effect of Self-efficacy
Table 3 & Correlation Matrix of Research Variables (N = 97)
The levels of uncertainty, self-efficacy, and self-care behaviors in women receiving chemotherapy for breast cancer are presented in Table 2. Mean (SD) uncertainty was 76.70 (13.55) on a scale of 28 to 140, mean (SD) self-efficacy was 27.15 (5.67) on a scale of 10 to 40, and mean (SD) self-care was 53.96 (6.08) on a scale of 15 to 75. Bivariate correlations among study variables are reported in Table 3.
1 j0.201a j0.032 j0.050 j0.040 0.040 j0.321b 0.243a 0.292b
Levels of Uncertainty, Self-efficacy, and Self-care Behavior
P G .05. P G.01.
A total of 97 women agreed to participate in this study. Table 1 presents patients’ demographic and medical characteristics. All of the patients were women with children. The mean (SD) age was 51.76 (9.016) years. About half of them completed high school education (42.3%). Most of the women were married (92.8%) and employed (67%). For most (77.4%), their family income each month was below 4000 Yuan (US$658, €479). Most of the women (71.1%) financed their healthcare for themselves. Most (80.4%) had the diagnosis of stage II breast cancer without any comorbidity. All were receiving chemotherapy or chemotherapy with radiotherapy. For approximately half (55.7%), the chemotherapy cycle length was 3 weeks.
1 0.359b 1 j0.054 0.005 1 0.083 0.058 j0.115 0.294b 0.100 j0.079 j0.039 j0.065 0.073 j0.008 0.082 0.169
11
1 j0.247a 0.111 0.084
Characteristics of the Sample
Uncertainty, Self-efficacy and Self-care in Breast Cancer
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Results
12
n
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of treatment, chemotherapy cycle length, and comorbidities.10,35Y42 One-tailed tests were used to explore the hypothesized directional relationships among uncertainty, self-efficacy, and self-care. A threshold of significance for all tests was set at .05. All analyses were performed using SPSS 20.0 (IBM Inc, Armonk, New York).
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Table 4 & Mediating Effects of Self-efficacy With Covariates of Demographic and Medical Variables (N = 97) Model Summary
Model 1 Model 2 Model 3
Coefficients
R2
P
Independent
Dependent
0.225 0.189 0.283
.031 .099 .006
Uncertainty Uncertainty Uncertainty Self-efficacy
SCB Self-efficacy SCB
" j.086 .086 j.111 .285
SE
Standardized "
P
.051 .049 .050 .111
j.192 .205 j.247 .266
.047 .960 .015 .006
Abbreviation: SCB, self-care behavior.
did not mediate the effects of uncertainty on self-care behavior. The total variance explained by all variables combined was 28.3%. Excluding the effect of covariates, uncertainty and self-efficacy explained 18.2% of the variance in self-care.
n
Discussion
The current study found moderate levels of uncertainty, selfefficacy, and self-care among the Chinese women sampled. Observed responses reflected nearly the full range of possible scores, indicating an array of individual differences on all 3 variables. The average level of uncertainty in our sample (76.70) was higher than that reported in previous studies using the MUIS-A 28-item scale, which reported scores ranging from 63.76 to 65.30 in a sample of Western patients with breast cancer.42 Women in the current sample were recently diagnosed and had few comorbidities. They would be expected to have more uncertainty because they lack any experiential frame of reference to define illness-related events.43 In addition, the low educational level of the sample in this study may have contributed to greater uncertainty35; less than 20% of our sample had more than a high school education. Moreover, many of our participants (77.4%) had family income of less than 4000 Yuan per month (US$658, €479), which is far below the average medical expense for inpatients in third-level hospitals (10 442.4 Yuan in 2010).44 Families spend almost 50% of their household income for healthcare expenses when a family member has cancer.45 The economic pressure combined with complex cancer treatment and limited illness experience and education may have led to greater feelings of uncertainty in this sample. The mean score for perceived self-efficacy found in this study (27.15) was similar to or slightly lower than those reported by other investigators, ranging from 27.4 to 31.91 for Western patients with cancer37,46,47 and 29.63 for Chinese women with breast cancer.48 Participants in the current sample were relatively young and most did not have a college education, factors that correlated with lower self-efficacy in previous studies.37,38 According to Bandura,49 past mastery experiences are an important resource in promoting self-efficacy beliefs, and patients who are young and without any disease history may be less confident in their coping ability. The level of self-care behavior reported in the current sample (53.96) is consistent with a previous study reporting a mean selfcare behavior score of 54.5 in the general population.33 We had expected to observe higher levels of self-care relative to the general
population given that the study participants were currently receiving chemotherapy and experiencing its adverse effects. It is possible that women were unaware of self-care strategies to cope with chemotherapy-related challenges or symptoms. It may also have been that others were providing care for these women at the time of assessment. Unlike most Western countries where chemotherapy is administered on an outpatient basis, these Chinese patients were hospitalized for the duration of their chemotherapy cycles. Being hospitalized may have resulted in less of a demand for self-care, as hospital staff and family members were present to provide assistance and support for the women with breast cancer. Other potential explanations may be related to the measure of self-care used in this study. The ASAS-R is a measure of general, not cancerspecific, self-care. Engagement in typical daily self-care may not have changed, while other less common (cancer-specific) self-care needs may have been considerably different. In addition, the ASAS-R items measure both actual self-care behavior and capacity to engage in self-care behavior. Participants may have reported low scores on capacity items while hospitalized and receiving chemotherapy. Evidence in this study partially supported our research hypotheses. We demonstrated that uncertainty was negatively correlated with self-care behavior, suggesting that the higher the level of uncertainty that patients feel, the less self-care they perform to cope with effects of the disease.12 Patients without sufficient information or knowledge cannot interpret illness situations easily and are restricted in presenting satisfying and appropriate self-care behavior when the breast cancer or its treatment is perceived as complex and difficult to predict. Therefore, providing uncertainty management is an essential component in self-care interventions for patients with breast cancer.9
Figure 2 n Observed relationships. *P G .05; **P G .01.
E24 n Cancer NursingTM, Vol. 38, No. 3, 2015 Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
Zhang et al
Our study also demonstrated that self-efficacy was positively correlated with self-care behavior, controlling for the effect of uncertainty. This finding is consistent with Bandura’s Selfefficacy theory,50 which indicates that individuals need to believe that they can put self-care activities into practice to exert sufficient effort and be able to perform self-care behavior. In other words, their self-efficacy facilitates the achievement of self-care goals and adaptation to illness.36 Thus, a second essential component of self-care interventions is strategies to enhance patients’ confidence and ability to engage in self-care activities. Not all of the research hypotheses were supported by the data. We hypothesized a negative relationship between uncertainty and self-efficacy, with greater levels of uncertainty eroding one’s confidence for coping with the challenge. Conversely, we found a positive relationship between uncertainty and self-efficacy, although not statistically significant. The direction of the relationship suggests that patients with higher levels of illness uncertainty tended to report greater confidence in their ability to manage difficult life situations. A similar relationship was demonstrated in spouse’s psychological adaptation to wives’ breast cancer diagnosis. Spouses who reported more uncertainty had greater confidence to emotionally support their wives and manage the impact of breast cancer.51 Although the sources of uncertainty and personal impact of cancer are different between women with breast cancer and their spouses, both may share a similar spirit of ‘‘rising to the challenge’’ and being positive and hopeful in the face of a lifethreatening diagnosis. How people with cancer appraise an uncertain situation is continually fluctuating. Future longitudinal evaluation may be useful to detect changes in uncertainty over time and how uncertainty influences self-efficacy at different points in the breast cancer trajectory. The mediating role of self-efficacy in the relationship between uncertainty and self-care behavior was also not supported. One explanation may be the selection of a generalized self-efficacy scale, rather than a cancer-specific self-efficacy scale. The GSE measures global confidence in one’s coping ability across all stressful situations, which may be perceived as a trait-like variable in this study. Illness uncertainty occurs when a specific cancer-related situation is complex, ambiguous, and unpredictable or when the patient lacks information about a specific cancer stressor, which is a more state-like variable.12 It is presumed that illness (cancerrelated) self-efficacy may be a stronger mediator of the relationship between uncertainty and self-care and that cancer-related self-efficacy may also be negatively rather than positively correlated with illness uncertainty. There are some limitations of this study that need to be taken into consideration. First, the results of this study were obtained from a convenience sample of women who all received chemotherapy during an inpatient stay at a university-affiliated hospital. They may not be representative of all Chinese women with breast cancer, particularly those who cannot access or afford third-level hospital care. Second, the study was cross-sectional and cannot account for temporal order of effects. In the current analysis, we cannot be sure that uncertainty and self-efficacy led to specific self-care activity. It is possible that successful self-care behaviors reduced uncertainty or improved one’s self-efficacy. Third, neither the self-efficacy nor the self-care measure was illness
Uncertainty, Self-efficacy and Self-care in Breast Cancer
(cancer) specific, which may have weakened our ability to detect mediation in this sample. Moreover, the self-care measure included items that measured both actual behavior and perceived behavioral ability. Fourth, the instruments used in the study were developed in the Western culture, and although all had good reliability, some (MUIS and ASAS-R) have not been validated for use with a Chinese mainland population. Fifth, an a priori power analysis was not done to determine sample size. Post hoc analysis indicated a power of 0.52 to 0.75 for observed relationships. However, we do not know if these observed effect sizes accurately estimate the true population effect sizes. Our sample of 97 participants is sufficient if the true effect sizes of the mediation pathways are large (> = 0.50, N = 26) or medium (> = 0.30, N = 82), but a larger sample size would be needed if the true effect sizes are small (> = 0.10, N = 779). Finally, we did not collect information about the exact length of time since diagnosis or chemotherapy cycle number. Observed responses may have been influenced by how ‘‘new’’ chemotherapy was to the patient (ie, how much treatment women had already had), although previous studies have demonstrated consistently greater uncertainty levels during the treatment period compared with posttreatment.3
n
Conclusion
Despite the limitations, the findings suggest some potential implications for clinical practice. Our results underscore the important roles that uncertainty and self-efficacy play in self-care behavior. Health professionals need to assess patients’ knowledge and information needs when facing a new cancer diagnosis and new treatment regimens with expected adverse effects. Nurses can help patients manage uncertainty by providing education and assisting patients to anticipate and correctly make sense of cancerrelated experiences. Nurses also need to build or restore patients’ confidence in their ability to successfully cope with these new challenges and help them to actively engage in self-care tasks. Intervention programs for women with breast cancer should emphasize tailored ways to reduce uncertainty and enhance perceptions of self-efficacy and controllability of unfamiliar experiences. Some uncertainty and self-efficacy interventions have demonstrated efficacy in Western samples of patients with cancer. Given the disparities in culture and economic status, these interventions could be revised and tested to meet the unique needs of Chinese women with breast cancer. ACKNOWLEDGMENTS
The authors express their appreciation to Ms Xiaoxing Wen for her assistance in back-translation of study questionnaires and to the patients and nursing staff in the Department of Oncology of the 3 hospitals for identifying participants in the process of data collection. The authors thank the Kwekkeboom research group for feedback on earlier versions of the manuscript.
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