Supportive care needs and psychological complaints among Mexican breast cancer patients
Perez Fortis, Adriana
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Publication date: 2018
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Perez Fortis, A. (2018). Supportive care needs and psychological complaints among Mexican breast cancer patients. University of Groningen.
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General discussion
CH
APT
ER
GENERAL DISCUSSION
The main goal of this research was to investigate the psychological complaints and supportive care needs of Mexican breast cancer patients, from diagnosis until shortly after finishing with primary medical treatment. Besides, we also explored the role of the perceived personal control and affective forecasting accuracy in relation to the psychological complaints and supportive care needs of the patients. In the present chapter, we summarize the main findings of the study, address some methodological considerations that the reader should consider for the interpretation of the results, emphasize the implications of our results for the clinical practice, and propose some suggestions for future research.
Major findings
Once we detected the paucity of literature on cancer-related psychosocial issues among Mexican breast cancer patients, particularly the shortage of research about the prevalence of anxiety and depressive symptoms, we decided to conduct a pilot study to examine the immediate psychological impact of a breast cancer diagnosis among Mexican women. The results obtained and described in chapter 2, made evident that a large proportion (88%) of Mexican breast cancer patients had clinical symptoms of anxiety immediately after hearing the diagnosis, while a smaller proportion (44%) of patients had clinical symptoms of depression. We did not identify significant differences by the sociodemographic and medical characteristics of the patients in their mean levels of anxiety or depressive symptoms. This result led us to conclude that regardless of patients’ marital status, age, education level, or cancer stage, receiving a breast cancer diagnosis implies a strong shock for most of the Mexican women. It was difficult to compare our results with other studies because there is almost none study investigating anxiety and depressive symptoms the same day that breast cancer patients are diagnosed. Nonetheless, longitudinal studies investigating anxiety symptoms among Western breast cancer patients reported the highest levels of anxiety symptoms at the diagnosis phase.1,2 Regarding depressive symptoms, the pattern is not very clear, a study reported the highest levels of depressive symptoms at the diagnosis phase,1 another suggested continuously moderately severe depressive symptoms among patients along the disease trajectory,2 and a recent meta-analysis reported a risk of an increase in depressive symptoms one year after diagnosis.3
The high rate of psychological complaints identified in the pilot study and the absence of longitudinal studies investigating psychological outcomes among Mexican breast cancer patients, drove us to plan an observational longitudinal study with a new sample of patients. In this second study, we investigated how anxiety and depressive symptoms changed from diagnosis until shortly after treatment. We also examined the
supportive care needs of breast cancer patients after diagnosis and over time. After one year of recruiting patients and over two years of data collection, we could analyze the course and predictors of anxiety and depressive symptoms as well as the course and predictors of supportive care needs.
In chapter 3, we reported that anxiety and depressive symptoms declined over time among Mexican breast cancer patients. The prevalence of clinical symptoms of anxiety remained higher than the prevalence of clinical symptoms of depression from diagnosis until ending treatment. This result highlights the relevance of investigating both symptoms separately instead of encompassing them in a more general concept like distress, which in the last years has been emphasized for screening among cancer patients. Our findings, thus, suggest that anxiety more than depressive symptoms, represent a main psychological complaint for Mexican breast cancer patients. Although, there are some patients that also deal with high levels of depressive symptoms. Chapter 3, also shows information on the predictors of the course of anxiety and depressive symptoms. Confirming previous studies with Western4,5 and Asian6,7 cancer patients, Mexican breast cancer patients with lower levels of perceived personal control at baseline showed higher levels of anxiety and depressive symptoms over time. This result was interesting because it suggests that the previously reported difference in the cultural meaning of perceived personal control between individualistic and collectivistic cultures8, might be not held when facing a chronic disease such as cancer. Regardless of patients' cultural background, having high perceptions that one can control the circumstances of our own life, might be protective against developing high psychological complaints when facing breast cancer. Also, suffering a negative life event in the 3 months previous to the diagnosis, and experiencing high levels of physical symptoms after the surgery, were associated to higher anxiety and depressive symptoms over time. Thus, these patients might be in higher risk of a psychological burden due to breast cancer.
In chapter 4 we showed the results on supportive care needs of Mexican breast cancer patients after diagnosis. Regardless of the sociodemographic and medical characteristics of Mexican breast cancer patients, they have mainly health system and information unmet care needs after diagnosis. One of the most prevalent care needs was having one member of hospital staff with whom patients can talk about all aspects of the disease. This finding is understandable because on average consultations last between 10 and 15 minutes, a very short time to deliver all the information about the disease and treatments. We also observed that patients with higher levels of depressive symptoms at baseline had higher psychological, physical and daily living, patient care and support, and additional supportive care needs, than patients with lower depressive symptoms. Comparing our results with the available literature on supportive care needs among breast cancer patients, we saw that among patients from low-middle income countries health system and information needs are highly prevalent and Mexico is not the exception. This
7
GENERAL DISCUSSION
The main goal of this research was to investigate the psychological complaints and supportive care needs of Mexican breast cancer patients, from diagnosis until shortly after finishing with primary medical treatment. Besides, we also explored the role of the perceived personal control and affective forecasting accuracy in relation to the psychological complaints and supportive care needs of the patients. In the present chapter, we summarize the main findings of the study, address some methodological considerations that the reader should consider for the interpretation of the results, emphasize the implications of our results for the clinical practice, and propose some suggestions for future research.
Major findings
Once we detected the paucity of literature on cancer-related psychosocial issues among Mexican breast cancer patients, particularly the shortage of research about the prevalence of anxiety and depressive symptoms, we decided to conduct a pilot study to examine the immediate psychological impact of a breast cancer diagnosis among Mexican women. The results obtained and described in chapter 2, made evident that a large proportion (88%) of Mexican breast cancer patients had clinical symptoms of anxiety immediately after hearing the diagnosis, while a smaller proportion (44%) of patients had clinical symptoms of depression. We did not identify significant differences by the sociodemographic and medical characteristics of the patients in their mean levels of anxiety or depressive symptoms. This result led us to conclude that regardless of patients’ marital status, age, education level, or cancer stage, receiving a breast cancer diagnosis implies a strong shock for most of the Mexican women. It was difficult to compare our results with other studies because there is almost none study investigating anxiety and depressive symptoms the same day that breast cancer patients are diagnosed. Nonetheless, longitudinal studies investigating anxiety symptoms among Western breast cancer patients reported the highest levels of anxiety symptoms at the diagnosis phase.1,2 Regarding depressive symptoms, the pattern is not very clear, a study reported the highest levels of depressive symptoms at the diagnosis phase,1 another suggested continuously moderately severe depressive symptoms among patients along the disease trajectory,2 and a recent meta-analysis reported a risk of an increase in depressive symptoms one year after diagnosis.3
The high rate of psychological complaints identified in the pilot study and the absence of longitudinal studies investigating psychological outcomes among Mexican breast cancer patients, drove us to plan an observational longitudinal study with a new sample of patients. In this second study, we investigated how anxiety and depressive symptoms changed from diagnosis until shortly after treatment. We also examined the
supportive care needs of breast cancer patients after diagnosis and over time. After one year of recruiting patients and over two years of data collection, we could analyze the course and predictors of anxiety and depressive symptoms as well as the course and predictors of supportive care needs.
In chapter 3, we reported that anxiety and depressive symptoms declined over time among Mexican breast cancer patients. The prevalence of clinical symptoms of anxiety remained higher than the prevalence of clinical symptoms of depression from diagnosis until ending treatment. This result highlights the relevance of investigating both symptoms separately instead of encompassing them in a more general concept like distress, which in the last years has been emphasized for screening among cancer patients. Our findings, thus, suggest that anxiety more than depressive symptoms, represent a main psychological complaint for Mexican breast cancer patients. Although, there are some patients that also deal with high levels of depressive symptoms. Chapter 3, also shows information on the predictors of the course of anxiety and depressive symptoms. Confirming previous studies with Western4,5 and Asian6,7 cancer patients, Mexican breast cancer patients with lower levels of perceived personal control at baseline showed higher levels of anxiety and depressive symptoms over time. This result was interesting because it suggests that the previously reported difference in the cultural meaning of perceived personal control between individualistic and collectivistic cultures8, might be not held when facing a chronic disease such as cancer. Regardless of patients' cultural background, having high perceptions that one can control the circumstances of our own life, might be protective against developing high psychological complaints when facing breast cancer. Also, suffering a negative life event in the 3 months previous to the diagnosis, and experiencing high levels of physical symptoms after the surgery, were associated to higher anxiety and depressive symptoms over time. Thus, these patients might be in higher risk of a psychological burden due to breast cancer.
In chapter 4 we showed the results on supportive care needs of Mexican breast cancer patients after diagnosis. Regardless of the sociodemographic and medical characteristics of Mexican breast cancer patients, they have mainly health system and information unmet care needs after diagnosis. One of the most prevalent care needs was having one member of hospital staff with whom patients can talk about all aspects of the disease. This finding is understandable because on average consultations last between 10 and 15 minutes, a very short time to deliver all the information about the disease and treatments. We also observed that patients with higher levels of depressive symptoms at baseline had higher psychological, physical and daily living, patient care and support, and additional supportive care needs, than patients with lower depressive symptoms. Comparing our results with the available literature on supportive care needs among breast cancer patients, we saw that among patients from low-middle income countries health system and information needs are highly prevalent and Mexico is not the exception. This
pattern is different from the one identified among Western breast cancer patients, where psychological care needs predominate over information needs.9
The results of the longitudinal data shown in chapter 5, suggested that, overall, supportive care needs decreased from diagnosis until shortly after finishing with the medical treatments. Health system and information needs remained the highest over time compared to the other supportive care needs dimensions. This trend has also been identified among breast cancer patients from Asian countries.10,11 The lack of longitudinal studies involving breast cancer patients from Western countries makes it difficult to state whether the pattern identified in our study is specific for patients from low-middle income countries or it might also apply for patients from high-income countries. The high levels of health system and information care needs among Mexican breast cancer patients over time, might be explained by the fact that in the public health system the services are organized in such a way that the available doctor in a specific time slot will serve the patients for that time slot, but not throughout the treatment trajectory. In other words, patients are being served by several doctors along the disease trajectory and there is not a care coordinator. This organizational structure might not benefit the patient-physician communication, neither allow a clear control of the information that is provided to the patient. Besides, the patients do not receive any brochures or leaflets with information about the disease and the treatments, throughout the disease process. Depressive symptoms at baseline were a consistent predictor of supportive care needs, i.e., the higher the depressive symptoms the more supportive care needs over time. This finding suggests that especially patients with high depressive symptoms have a higher need for receiving help to meet their care needs, thus they should receive supportive care with priority. So far, most of the literature on supportive care needs has studied the role of depressive symptoms as predictor and supportive care needs as outcome,9 but it might be interesting to investigate this relationship in the opposite direction as well. It is likely that high unmet supportive care needs might also lead to higher depressive symptoms.
We also explored how accurate Mexican breast cancer patients were in predicting their positive and negative affect (affective forecasting accuracy), after receiving medical treatments and whether their levels of accuracy were related with their psychological care needs. The results presented in chapter 6 indicated that, in general, patients who followed neoadjuvant treatment (chemotherapy, radiotherapy or the combination of both) were rather accurate in predicting their positive and negative affect, whereas patients who had surgery overestimated their negative affect significantly. Specifically, among the patients who had surgery, we observed that the affective forecasting accuracy was related with their psychological care needs. Particularly, the subgroup of patients who underestimated the negative affect to the surgery, showed the highest psychological care needs. Health practitioners should be aware that not all patients who anticipate a high level of negative affect will be the ones with the highest psychological care needs, but on the contrary,
patients who do not anticipate high levels of negative affect might be at higher risk of having high psychological care needs post-surgery.
Methodological considerations
Sample and response rate
Participants in our research were solely recruited in one public hospital in Mexico City, which it might raise some concerns about the generalizability of our findings, thus, we would like to clarify on this. Because this study was managed from The Netherlands, in close collaboration with the National Medical Center `La Raza´, and the faculty of Psychology at the National University Autonomous of Mexico (UNAM in Spanish), both in Mexico City, we considered more feasible to conduct the study in only one hospital. Particularly, because arranging ethical approvals for the research protocol in different hospitals would have taken more time, and managing data collection from the distance in several hospitals in a large city, might be risky for data quality. Yet, we acknowledge that it would have been better to perform a multicenter study including several hospitals. We selected a public hospital because most of the population in Mexico (about 71% of the population) receive health care from public health institutions, and we wanted that our results were representative of most of the Mexican breast cancer patients in Mexico. Only a small proportion of the population are treated in costly private hospitals.
In Mexico, there are several social security institutions providing public healthcare services, but the largest is the Mexican Social Security Institute (IMSS in Spanish). This institute provides public healthcare services to around 60% of the population throughout the country, i.e., 70 million of Mexicans are affiliated to this institute.12 We chose a public hospital from the IMSS to collect our data because we tried that the medical approach was representative of most of the public hospitals in Mexico. Thus, our findings are representative of patients treated in a public hospital in Mexico. Perhaps there might be a different pattern of supportive care needs among patients treated in private hospitals, because it is likely that medical consultations are longer, therefore, patients might have more time to ask questions.
In both studies, a consecutive sample method was used. Unlike the cross-sectional study, in which we reached a high response rate (92%), for the longitudinal study the response rate was lower (66%) at T1. The lower response rate in the longitudinal phase might be explained by the fact that patients were informed that we would require their participation in several times along the disease treatment. Furthermore, the literature on recruitment and retention of participants in studies with low-income or minority populations suggests that factors like the economic disadvantages, distrust in the health care system, or the lack of awareness of research studies might be an added challenge in recruiting and retaining participants.13,14 Besides, no incentives were available for the participants and it has been shown that incentives, particularly in longitudinal studies, are associated with an
7
pattern is different from the one identified among Western breast cancer patients, wherepsychological care needs predominate over information needs.9
The results of the longitudinal data shown in chapter 5, suggested that, overall, supportive care needs decreased from diagnosis until shortly after finishing with the medical treatments. Health system and information needs remained the highest over time compared to the other supportive care needs dimensions. This trend has also been identified among breast cancer patients from Asian countries.10,11 The lack of longitudinal studies involving breast cancer patients from Western countries makes it difficult to state whether the pattern identified in our study is specific for patients from low-middle income countries or it might also apply for patients from high-income countries. The high levels of health system and information care needs among Mexican breast cancer patients over time, might be explained by the fact that in the public health system the services are organized in such a way that the available doctor in a specific time slot will serve the patients for that time slot, but not throughout the treatment trajectory. In other words, patients are being served by several doctors along the disease trajectory and there is not a care coordinator. This organizational structure might not benefit the patient-physician communication, neither allow a clear control of the information that is provided to the patient. Besides, the patients do not receive any brochures or leaflets with information about the disease and the treatments, throughout the disease process. Depressive symptoms at baseline were a consistent predictor of supportive care needs, i.e., the higher the depressive symptoms the more supportive care needs over time. This finding suggests that especially patients with high depressive symptoms have a higher need for receiving help to meet their care needs, thus they should receive supportive care with priority. So far, most of the literature on supportive care needs has studied the role of depressive symptoms as predictor and supportive care needs as outcome,9 but it might be interesting to investigate this relationship in the opposite direction as well. It is likely that high unmet supportive care needs might also lead to higher depressive symptoms.
We also explored how accurate Mexican breast cancer patients were in predicting their positive and negative affect (affective forecasting accuracy), after receiving medical treatments and whether their levels of accuracy were related with their psychological care needs. The results presented in chapter 6 indicated that, in general, patients who followed neoadjuvant treatment (chemotherapy, radiotherapy or the combination of both) were rather accurate in predicting their positive and negative affect, whereas patients who had surgery overestimated their negative affect significantly. Specifically, among the patients who had surgery, we observed that the affective forecasting accuracy was related with their psychological care needs. Particularly, the subgroup of patients who underestimated the negative affect to the surgery, showed the highest psychological care needs. Health practitioners should be aware that not all patients who anticipate a high level of negative affect will be the ones with the highest psychological care needs, but on the contrary,
patients who do not anticipate high levels of negative affect might be at higher risk of having high psychological care needs post-surgery.
Methodological considerations
Sample and response rate
Participants in our research were solely recruited in one public hospital in Mexico City, which it might raise some concerns about the generalizability of our findings, thus, we would like to clarify on this. Because this study was managed from The Netherlands, in close collaboration with the National Medical Center `La Raza´, and the faculty of Psychology at the National University Autonomous of Mexico (UNAM in Spanish), both in Mexico City, we considered more feasible to conduct the study in only one hospital. Particularly, because arranging ethical approvals for the research protocol in different hospitals would have taken more time, and managing data collection from the distance in several hospitals in a large city, might be risky for data quality. Yet, we acknowledge that it would have been better to perform a multicenter study including several hospitals. We selected a public hospital because most of the population in Mexico (about 71% of the population) receive health care from public health institutions, and we wanted that our results were representative of most of the Mexican breast cancer patients in Mexico. Only a small proportion of the population are treated in costly private hospitals.
In Mexico, there are several social security institutions providing public healthcare services, but the largest is the Mexican Social Security Institute (IMSS in Spanish). This institute provides public healthcare services to around 60% of the population throughout the country, i.e., 70 million of Mexicans are affiliated to this institute.12 We chose a public hospital from the IMSS to collect our data because we tried that the medical approach was representative of most of the public hospitals in Mexico. Thus, our findings are representative of patients treated in a public hospital in Mexico. Perhaps there might be a different pattern of supportive care needs among patients treated in private hospitals, because it is likely that medical consultations are longer, therefore, patients might have more time to ask questions.
In both studies, a consecutive sample method was used. Unlike the cross-sectional study, in which we reached a high response rate (92%), for the longitudinal study the response rate was lower (66%) at T1. The lower response rate in the longitudinal phase might be explained by the fact that patients were informed that we would require their participation in several times along the disease treatment. Furthermore, the literature on recruitment and retention of participants in studies with low-income or minority populations suggests that factors like the economic disadvantages, distrust in the health care system, or the lack of awareness of research studies might be an added challenge in recruiting and retaining participants.13,14 Besides, no incentives were available for the participants and it has been shown that incentives, particularly in longitudinal studies, are associated with an
increase in participation and retention rates.15 The type of non-response was unknown, because descriptive data on non-respondents was not possible to collect.
Ethical issues
In the first cross-sectional study, we approached patients right after receiving the breast cancer diagnosis, which might raise ethical concerns. Is it ethical to approach people in a moment, which might trigger an emotional crisis and invite them to participate in a psychological research? Are patients able to comprehend and to be aware of participating in research? All the patients in our study were approached by a clinical psychologist, who first asked the patients whether they desired to talk about the diagnosis just received. For those patients who were in shock (i.e. burst into tears, emotional crisis) because of the diagnosis, the psychologist made a brief crisis intervention to support the patient. Then, the psychologist explained the study and invited the patients to participate. Those who accepted and signed the informed consent were interviewed to fill in the self-reports. Some contextual factors should be taken into account to judge the ethical implications. The consultations where doctors deliver the diagnosis and provide information about the next steps for the treatment are rather brief, i.e., between 10 to 15 minutes. Besides, the psychosocial care for cancer patients is almost absent, focusing specially in the provision of palliative care for patients in advanced stages of the disease. Thus, the fact that most of the patients accepted to participate in this cross-sectional study might be an indication that patients valued in a positive way the opportunity to talk with a psychologist about their diagnosis. It might also be that patients were too distressed over the situation whereof to resist to express their emotions.
Attrition issue
Regarding the follow-up of the patients in the longitudinal study, overall the attrition rate was low, i.e., around 10% after baseline (patients with only one measurement) and around 28% at the last measure point. When comparing sociodemographic, medical, and psychological (anxiety and depressive symptoms) characteristics of the dropouts after baseline (n = 17) versus respondents at follow-up stages (n = 155), we only identified significant differences by the number of children. However, we identified significant differences by education and cancer stage between full respondents (n = 124) and the dropouts in the last follow-up wave (n = 48) (see the flowchart of participants in chapter 3). There was a higher attrition rate among the patients in more advanced stages of the disease, which it might be related to the higher death rate in this group, and a lower proportion of patients with low education remained in the study until the last follow-up wave. This information might cause concerns about the possibility of selective attrition and therefore bias in our results. Thus, it should be taken into account in the interpretation of our findings.
Selective attrition is a common problem in longitudinal studies, especially when involving patients with advanced cancer, as patients in advanced stages of the disease are more likely to withdraw of the study because they are more ill or they have died.13,15–17 However, recent studies indicate that selective attrition does not always affect the estimates of associations between variables.18,19 Specifically in our study, mixed models prevent biased estimates by using the maximum likelihood method. This method does not impute any missing data. It estimates parameters directly using all the information that is already contained in the incomplete data set, i.e., it obtains parameter estimates by maximizing the likelihood function of the incomplete data.20,21
Missing data
In our study, missing data were not a real problem, all questions were answered (see below data collection section). Nonetheless, we had patients with missing measurements by the study design. Given that the assessment points were linked to the type of treatment followed by the patients, some patients had 3, 4 or 5 measurements, based on the treatment trajectory they followed. Taking into account these missing measurements we selected linear mixed models approach to analyze our longitudinal data. Linear mixed models have the advantage of (1) including all the patients with at least one observation in the measure point, (2) dealing with unequal repeated measurements, and (3) there may be different moments of repeated measurements.22 In general, with linear mixed models missing data is not a problem. These models handle missing data by assuming to be missing at random.23 In our study, we assumed the missing values to be at random.
Statistical analyses
Two of the most common statistical approaches used to analyze changes in longitudinal data are the mixed models and the latent class growth models. Both models allow analyzing individual trajectories over time and creating subgroups, however, the way to identify subgroups is the main difference between both approaches.23
Mixed models shape the average trajectory of the outcome variable in the whole sample assuming that one single average trajectory describes the individual trajectories of all participants. These models only allow grouping participants into predefined categories based on observed variables (e.g. sex, age group, socioeconomic status), i.e., a-priori selection of subgroups. Thus, we get average trajectories for each subgroup. Contrary, the main aim of latent class growth models is to statistically classify individuals into different groups, therefore, one single trajectory is not considered sufficient to describe the trajectories of all participants. This approach makes use of latent variables inferred from data, to create subgroups of individuals with comparable trajectories over time that might be in higher or lower risk of developing the target outcome. Thus, subgroups are not based on predefined observed variables.
7
increase in participation and retention rates.15 The type of non-response was unknown,because descriptive data on non-respondents was not possible to collect. Ethical issues
In the first cross-sectional study, we approached patients right after receiving the breast cancer diagnosis, which might raise ethical concerns. Is it ethical to approach people in a moment, which might trigger an emotional crisis and invite them to participate in a psychological research? Are patients able to comprehend and to be aware of participating in research? All the patients in our study were approached by a clinical psychologist, who first asked the patients whether they desired to talk about the diagnosis just received. For those patients who were in shock (i.e. burst into tears, emotional crisis) because of the diagnosis, the psychologist made a brief crisis intervention to support the patient. Then, the psychologist explained the study and invited the patients to participate. Those who accepted and signed the informed consent were interviewed to fill in the self-reports. Some contextual factors should be taken into account to judge the ethical implications. The consultations where doctors deliver the diagnosis and provide information about the next steps for the treatment are rather brief, i.e., between 10 to 15 minutes. Besides, the psychosocial care for cancer patients is almost absent, focusing specially in the provision of palliative care for patients in advanced stages of the disease. Thus, the fact that most of the patients accepted to participate in this cross-sectional study might be an indication that patients valued in a positive way the opportunity to talk with a psychologist about their diagnosis. It might also be that patients were too distressed over the situation whereof to resist to express their emotions.
Attrition issue
Regarding the follow-up of the patients in the longitudinal study, overall the attrition rate was low, i.e., around 10% after baseline (patients with only one measurement) and around 28% at the last measure point. When comparing sociodemographic, medical, and psychological (anxiety and depressive symptoms) characteristics of the dropouts after baseline (n = 17) versus respondents at follow-up stages (n = 155), we only identified significant differences by the number of children. However, we identified significant differences by education and cancer stage between full respondents (n = 124) and the dropouts in the last follow-up wave (n = 48) (see the flowchart of participants in chapter 3). There was a higher attrition rate among the patients in more advanced stages of the disease, which it might be related to the higher death rate in this group, and a lower proportion of patients with low education remained in the study until the last follow-up wave. This information might cause concerns about the possibility of selective attrition and therefore bias in our results. Thus, it should be taken into account in the interpretation of our findings.
Selective attrition is a common problem in longitudinal studies, especially when involving patients with advanced cancer, as patients in advanced stages of the disease are more likely to withdraw of the study because they are more ill or they have died.13,15–17 However, recent studies indicate that selective attrition does not always affect the estimates of associations between variables.18,19 Specifically in our study, mixed models prevent biased estimates by using the maximum likelihood method. This method does not impute any missing data. It estimates parameters directly using all the information that is already contained in the incomplete data set, i.e., it obtains parameter estimates by maximizing the likelihood function of the incomplete data.20,21
Missing data
In our study, missing data were not a real problem, all questions were answered (see below data collection section). Nonetheless, we had patients with missing measurements by the study design. Given that the assessment points were linked to the type of treatment followed by the patients, some patients had 3, 4 or 5 measurements, based on the treatment trajectory they followed. Taking into account these missing measurements we selected linear mixed models approach to analyze our longitudinal data. Linear mixed models have the advantage of (1) including all the patients with at least one observation in the measure point, (2) dealing with unequal repeated measurements, and (3) there may be different moments of repeated measurements.22 In general, with linear mixed models missing data is not a problem. These models handle missing data by assuming to be missing at random.23 In our study, we assumed the missing values to be at random. Statistical analyses
Two of the most common statistical approaches used to analyze changes in longitudinal data are the mixed models and the latent class growth models. Both models allow analyzing individual trajectories over time and creating subgroups, however, the way to identify subgroups is the main difference between both approaches.23
Mixed models shape the average trajectory of the outcome variable in the whole sample assuming that one single average trajectory describes the individual trajectories of all participants. These models only allow grouping participants into predefined categories based on observed variables (e.g. sex, age group, socioeconomic status), i.e., a-priori selection of subgroups. Thus, we get average trajectories for each subgroup. Contrary, the main aim of latent class growth models is to statistically classify individuals into different groups, therefore, one single trajectory is not considered sufficient to describe the trajectories of all participants. This approach makes use of latent variables inferred from data, to create subgroups of individuals with comparable trajectories over time that might be in higher or lower risk of developing the target outcome. Thus, subgroups are not based on predefined observed variables.
In the present study, we used the mixed model approach over the latent class growth model to analyze the course of supportive care needs, anxiety and depressive symptoms for two main reasons, (a) these models are well suited for unequal number of repeated measurements, and (b) the main aim of this research was to investigate the average course of our outcomes in the whole sample. As there are no previous longitudinal studies among Mexican breast cancer patients on psychosocial outcomes, we considered that the first step would be to get an overview of how patients’ supportive care needs and psychological complaints change in general.
Data collection
In relation to the data collection, we would like to stress that most of the patients attending public hospitals in Mexico are middle to low educated and not used to self-reports. Therefore, in order to guarantee the quality of the data, we decided to use interviewers to collect the data in both studies, the cross-sectional and the longitudinal. Using face-to-face interviews as method to collect data has its advantages and disadvantages. The main advantage for our study was that by using interviewers we prevented missing responses, given that interviewers made sure that all questions were answered. Particularly, for the longitudinal phase, it has been indicated that face-to-face interviews also contributes to increase the retention rates.15 The main disadvantage of face-to-face interviews is that interviewers might induce bias in the answers of respondents, especially because the questionnaires that we used were meant to be administered by means of self-report. Three of the most common types of bias in face-to-face interviews are social desirability bias, acquiescence bias and interviewer bias.24,25 In order to reduce social desirability bias, we assured confidentiality to the participants. To prevent interviewer bias, we prepared a manual for the interviewers and they received training about the process of interviewing a cancer patient before starting the data collection. In our study five interviewers participated throughout the study.
Research and clinical implications
The present study was the first one investigating supportive care needs, and anxiety and depressive symptoms from a longitudinal approach among a sample of breast cancer patients from a Latin American region. By doing so our results, (1) contribute to filling the gap of research on psychosocial issues of cancer in samples of cancer patients from low-middle income countries,26,27 (2) provide knowledge on a group of patients that has been underrepresented in the psycho-oncological literature, and (3) attend the call from non-governmental institutions such as the World Health Organization and from literature on cancer control in the Latin American region,28,29 to identify unmet needs as a starting point to implement supportive care services among cancer patients from low-middle income countries and in general to improve care. Besides, our research obeys the demand from
the field on supportive care research, about performing longitudinal studies, in order to identify specific needs at the different phases of cancer treatment, especially in the early survivorship phase after ending treatments.30,31
Assessing the course and predictors of supportive care needs and psychological complaints from diagnosis until ending the treatment among Mexican women suffering from breast cancer also have clinical implications for the different stakeholders in Mexico. Governmental institutions that regulate the Mexican healthcare system might consider giving higher priority to the psychosocial issues and supportive care needs that Mexican breast cancer patients experience along the cancer treatment, because so far supportive care services within public health systems from low-middle income countries are rather limited or absent.26,27 Likewise, the role of the mental health professionals might be more emphasized within the medical treatment teams focused on cancer care planning. Health policy makers could make use of our results to identify the supportive care needs and psychological complaints that might be addressed with priority, as it has been suggested that especially in low-middle income countries the distribution of resources allocated to cancer care programs should be based on empirical research.32 Thus, they could prioritize resources to cover the health system and information unmet needs of Mexican breast cancer patients along the disease trajectory, and to treat the anxiety symptoms of patients particularly after diagnosis.
Oncologists might reconsider the way that information about diagnosis and treatment is offered to the patients, taking into account that the emotional impact of the diagnosis could influence the attention and awareness of the patients to understand the information they are receiving.33,34 They should guarantee that the information they provide to the patients is clear and understandable for each patient. Thus, they might consider to provide brochures or leaflets to the patients with information about the disease, treatment and care.
Psychosocial care professionals might offer their services with priority to (1) the patients with the highest levels of anxiety or depressive symptoms, especially after the diagnosis, (2) the patients with low levels of perceived personal control because they are in risk of experiencing higher anxiety and depressive symptoms along the disease treatment, and (3) the patients experiencing high levels of physical symptoms after the surgery because they also showed high anxiety and depressive symptoms over time.
Finally, our findings might also be of interest for Mexican women who are dealing with this disease as well as for their families. Our results might help them to be informed about the psychosocial issues associated to the disease.
All the stakeholders mentioned above could consider how to integrate systematic and standardized supportive care services into the Mexican health system to cover the unmet needs and to relieve the psychological complaints of Mexican breast cancer patients. They might analyze whether it is necessary to make changes in the organizational
7
In the present study, we used the mixed model approach over the latent classgrowth model to analyze the course of supportive care needs, anxiety and depressive symptoms for two main reasons, (a) these models are well suited for unequal number of repeated measurements, and (b) the main aim of this research was to investigate the average course of our outcomes in the whole sample. As there are no previous longitudinal studies among Mexican breast cancer patients on psychosocial outcomes, we considered that the first step would be to get an overview of how patients’ supportive care needs and psychological complaints change in general.
Data collection
In relation to the data collection, we would like to stress that most of the patients attending public hospitals in Mexico are middle to low educated and not used to self-reports. Therefore, in order to guarantee the quality of the data, we decided to use interviewers to collect the data in both studies, the cross-sectional and the longitudinal. Using face-to-face interviews as method to collect data has its advantages and disadvantages. The main advantage for our study was that by using interviewers we prevented missing responses, given that interviewers made sure that all questions were answered. Particularly, for the longitudinal phase, it has been indicated that face-to-face interviews also contributes to increase the retention rates.15 The main disadvantage of face-to-face interviews is that interviewers might induce bias in the answers of respondents, especially because the questionnaires that we used were meant to be administered by means of self-report. Three of the most common types of bias in face-to-face interviews are social desirability bias, acquiescence bias and interviewer bias.24,25 In order to reduce social desirability bias, we assured confidentiality to the participants. To prevent interviewer bias, we prepared a manual for the interviewers and they received training about the process of interviewing a cancer patient before starting the data collection. In our study five interviewers participated throughout the study.
Research and clinical implications
The present study was the first one investigating supportive care needs, and anxiety and depressive symptoms from a longitudinal approach among a sample of breast cancer patients from a Latin American region. By doing so our results, (1) contribute to filling the gap of research on psychosocial issues of cancer in samples of cancer patients from low-middle income countries,26,27 (2) provide knowledge on a group of patients that has been underrepresented in the psycho-oncological literature, and (3) attend the call from non-governmental institutions such as the World Health Organization and from literature on cancer control in the Latin American region,28,29 to identify unmet needs as a starting point to implement supportive care services among cancer patients from low-middle income countries and in general to improve care. Besides, our research obeys the demand from
the field on supportive care research, about performing longitudinal studies, in order to identify specific needs at the different phases of cancer treatment, especially in the early survivorship phase after ending treatments.30,31
Assessing the course and predictors of supportive care needs and psychological complaints from diagnosis until ending the treatment among Mexican women suffering from breast cancer also have clinical implications for the different stakeholders in Mexico. Governmental institutions that regulate the Mexican healthcare system might consider giving higher priority to the psychosocial issues and supportive care needs that Mexican breast cancer patients experience along the cancer treatment, because so far supportive care services within public health systems from low-middle income countries are rather limited or absent.26,27 Likewise, the role of the mental health professionals might be more emphasized within the medical treatment teams focused on cancer care planning. Health policy makers could make use of our results to identify the supportive care needs and psychological complaints that might be addressed with priority, as it has been suggested that especially in low-middle income countries the distribution of resources allocated to cancer care programs should be based on empirical research.32 Thus, they could prioritize resources to cover the health system and information unmet needs of Mexican breast cancer patients along the disease trajectory, and to treat the anxiety symptoms of patients particularly after diagnosis.
Oncologists might reconsider the way that information about diagnosis and treatment is offered to the patients, taking into account that the emotional impact of the diagnosis could influence the attention and awareness of the patients to understand the information they are receiving.33,34 They should guarantee that the information they provide to the patients is clear and understandable for each patient. Thus, they might consider to provide brochures or leaflets to the patients with information about the disease, treatment and care.
Psychosocial care professionals might offer their services with priority to (1) the patients with the highest levels of anxiety or depressive symptoms, especially after the diagnosis, (2) the patients with low levels of perceived personal control because they are in risk of experiencing higher anxiety and depressive symptoms along the disease treatment, and (3) the patients experiencing high levels of physical symptoms after the surgery because they also showed high anxiety and depressive symptoms over time.
Finally, our findings might also be of interest for Mexican women who are dealing with this disease as well as for their families. Our results might help them to be informed about the psychosocial issues associated to the disease.
All the stakeholders mentioned above could consider how to integrate systematic and standardized supportive care services into the Mexican health system to cover the unmet needs and to relieve the psychological complaints of Mexican breast cancer patients. They might analyze whether it is necessary to make changes in the organizational
structure of the public hospitals, and which strategies would be effective to meet the patients’ care needs.
Research from the field of health services suggest that prior to implement evidence-based interventions it is necessary to assess the organizational readiness for change of the health care institutions and the willingness of the patients to accept and engage in supportive care.35,36
Suggestions for future research
After four years working within a Mexican public hospital, it is clear that several research questions on psychosocial issues of cancer and supportive care remain unanswered in the Mexican context. There is a great need for more research to be done within the field of psychosocial oncology involving Mexican cancer patients. Taking into account our results, we consider it is essential to investigate the factors that contribute to the high levels of anxiety among Mexican breast cancer patients. In the present study, we investigated the role of anxiety and depressive symptoms as predictors of supportive care needs, but it might also be interesting to explore whether unmet supportive care needs, particularly unmet information care needs, could be related with higher anxiety and depressive symptoms. It might be that the lack of information about diagnosis and treatment could trigger more anxiety symptoms.37 Future studies might also explore whether the pre-conceptions or perceptions that Mexican women have in relation to breast cancer might contribute to their anxiety symptoms.38
We also consider pertinent to conduct empirical studies to assess the current state of supportive care services within the Mexican healthcare system, in order to know the availability of services and the readiness to receive supportive cancer care services among the Mexican patients.39 It might also be necessary to investigate whether Mexican breast cancer patients desire to receive psychological support, the modality of support that they would prefer and from whom they wish to receive the care. This information might be helpful to implement programs according to the patients’ desire and needs.40
Regarding the high levels of health system and information care needs identified among the Mexican breast cancer patients, we suggest to investigate the patient-physician communication and the health literacy of the patients. For instance, qualitative studies might inquire whether there is a lack of information provision, considering the time pressure due to the short duration of the consultations, or whether the information that is provided is not clearly understood by the patients, or other type of communication errors happen. Investigating these factors might shed light on the type of interventions, that need to be designed and implemented to better meet the information care needs of Mexican breast cancer patients. Recent evidence suggest that oncology nurses have a potential role in addressing patients’ needs, particularly, in low-middle income countries where the role of nurses in the outpatient consultations has been relegated to receive the patient and
scheduling appointments.41 Besides, nowadays the use of e-health strategies has gained ground not only among high income countries, but also among low-middle income contexts.42 Thus, it might be relevant to consider the use of e-health interventions to facilitate the communication between patients and the physician and to address the unmet care needs of the patients.43
Concluding remarks
Our findings provide an overview of the main psychological complaints and supportive care needs of Mexican breast cancer patients from diagnosis until ending the primary medical treatment. Overall, these results help to better understand the psychosocial aspects of breast cancer among Mexican women.
Mexican breast cancer patients mainly deal with anxiety symptoms, but some of them also deal with depressive symptoms. The highest levels of these symptoms occur at the diagnosis phase and decrease over the disease treatment. Patients with lower levels of perceived personal control at diagnosis are more susceptible to develop higher anxiety and depressive symptoms over time. Therefore, health professionals might prioritize supportive care services to these patients.
In general, Mexican women dealing with breast cancer mainly have health system and information care needs over the diagnosis and treatment of the disease. Thus, the different stakeholders might consider taking actions to address these unmet supportive care needs.
7
structure of the public hospitals, and which strategies would be effective to meet thepatients’ care needs.
Research from the field of health services suggest that prior to implement evidence-based interventions it is necessary to assess the organizational readiness for change of the health care institutions and the willingness of the patients to accept and engage in supportive care.35,36
Suggestions for future research
After four years working within a Mexican public hospital, it is clear that several research questions on psychosocial issues of cancer and supportive care remain unanswered in the Mexican context. There is a great need for more research to be done within the field of psychosocial oncology involving Mexican cancer patients. Taking into account our results, we consider it is essential to investigate the factors that contribute to the high levels of anxiety among Mexican breast cancer patients. In the present study, we investigated the role of anxiety and depressive symptoms as predictors of supportive care needs, but it might also be interesting to explore whether unmet supportive care needs, particularly unmet information care needs, could be related with higher anxiety and depressive symptoms. It might be that the lack of information about diagnosis and treatment could trigger more anxiety symptoms.37 Future studies might also explore whether the pre-conceptions or perceptions that Mexican women have in relation to breast cancer might contribute to their anxiety symptoms.38
We also consider pertinent to conduct empirical studies to assess the current state of supportive care services within the Mexican healthcare system, in order to know the availability of services and the readiness to receive supportive cancer care services among the Mexican patients.39 It might also be necessary to investigate whether Mexican breast cancer patients desire to receive psychological support, the modality of support that they would prefer and from whom they wish to receive the care. This information might be helpful to implement programs according to the patients’ desire and needs.40
Regarding the high levels of health system and information care needs identified among the Mexican breast cancer patients, we suggest to investigate the patient-physician communication and the health literacy of the patients. For instance, qualitative studies might inquire whether there is a lack of information provision, considering the time pressure due to the short duration of the consultations, or whether the information that is provided is not clearly understood by the patients, or other type of communication errors happen. Investigating these factors might shed light on the type of interventions, that need to be designed and implemented to better meet the information care needs of Mexican breast cancer patients. Recent evidence suggest that oncology nurses have a potential role in addressing patients’ needs, particularly, in low-middle income countries where the role of nurses in the outpatient consultations has been relegated to receive the patient and
scheduling appointments.41 Besides, nowadays the use of e-health strategies has gained ground not only among high income countries, but also among low-middle income contexts.42 Thus, it might be relevant to consider the use of e-health interventions to facilitate the communication between patients and the physician and to address the unmet care needs of the patients.43
Concluding remarks
Our findings provide an overview of the main psychological complaints and supportive care needs of Mexican breast cancer patients from diagnosis until ending the primary medical treatment. Overall, these results help to better understand the psychosocial aspects of breast cancer among Mexican women.
Mexican breast cancer patients mainly deal with anxiety symptoms, but some of them also deal with depressive symptoms. The highest levels of these symptoms occur at the diagnosis phase and decrease over the disease treatment. Patients with lower levels of perceived personal control at diagnosis are more susceptible to develop higher anxiety and depressive symptoms over time. Therefore, health professionals might prioritize supportive care services to these patients.
In general, Mexican women dealing with breast cancer mainly have health system and information care needs over the diagnosis and treatment of the disease. Thus, the different stakeholders might consider taking actions to address these unmet supportive care needs.
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