Abstract
Background:
Communication about prognosis is a key ingredient of effective palliative care. When patients with advanced cancer develop increased prognostic understanding, there is potential for existential distress to occur. However, the existential dimensions of prognosis communication are underexplored.
Objective:
To describe the existential dimensions of prognosis communication in naturally-occurring palliative care conversations.
Methods:
This study was an explanatory sequential mixed methods design. We analyzed a random subset of patients from the Palliative Care Communication Research Initiative (PCCRI) parent study (n = 34, contributing to 45 palliative care conversations). Data were based on audio-recorded and transcribed inpatient palliative care conversations between adults with advanced cancer, their families, and palliative care clinicians. We stratified the study sample by levels of prognosis communication, and qualitatively examined patterns of existential communication, comparing the intensity, frequency, and content, within and across levels.
Results:
Existential communication was more common, and of stronger intensity, within conversations with higher levels of prognosis communication. Conversations with more prognosis communication appeared to exhibit a shift toward the existential and away from the more physical nature of the serious illness experience.
Conclusion:
Existential and prognosis communication are intimately linked within palliative care conversations. Results highlight the multiplicity and mutuality of concerns that arise when contemplating mortality, drawing attention to areas of palliative care communication that warrant future research.
Introduction
Recent evidence suggests that communication about prognosis—the process of addressing “what to expect” for an individual's disease course—is a salient component of effective palliative care.1–3 By enabling meaningful decision making and end-of-life planning in the setting of advanced illness,4–7 prognosis communication appears to be an important mechanism through which palliative care impacts preference-concordant treatment at the end of life.8,9 However, willingness to discuss prognosis (specifically related to life expectancy) has been associated with loss of meaning and purpose in terminally ill cancer patients. 10 In addition, previous studies in patients with advanced cancer have reported a relationship between increased prognostic understanding and greater existential distress.11,12 Given this link, and the importance of prognosis communication in palliative care, a better empirical understanding of how these dimensions of conversation interrelate is warranted.
Existential experience can be understood as a moment or situation, in which an individual confronts the boundaries of life, encountering the fragility of existence, and must renegotiate their fundamental understanding of the self, life, and death. 13 Qualitative research investigating the intersection between existential experience and prognosis communication has been primarily interview-based, asking individuals to reflect back on serious illness conversations.14,15 This research suggests that overemphasizing the instrumental aspects of serious illness conversations, while ignoring the inescapable existential dimensions (i.e., talking about the fact of death without addressing the process of dying), may limit the potential meaningful impact these conversations can have. 15 Yet, little observational research has been conducted to examine how these features of palliative care conversations are voiced and intersect in the natural clinical setting.
We aimed, therefore, to describe the existential dimensions of prognosis communication in naturally occurring palliative care conversations with adults with advanced cancer. Ultimately, understanding existing patterns of palliative care communication is critical to establish “best practices” for conversations related to prognosis in the setting of serious illness and to achieve the full benefits of palliative care.
Methods
We used an explanatory sequential mixed methods approach16,17 to analyze palliative care consultation transcripts from the Palliative Care Communication Research Initiative (PCCRI) parent study. 18 An explanatory sequential mixed methods design involves using qualitative data to explain or expand upon quantitative findings.16,17 For the present study, we formed groups based on quantitative results and used these groups to guide sampling and analysis of qualitative data. 19 Specifically, we used quantified data on frequency of prognosis expressions (i.e., none, low, and high levels) from the parent PCCRI study to guide our qualitative analysis of palliative care conversations, exploring whether and how existential communication differed within and across levels of prognosis strata.
As described more fully elsewhere, 18 the PCCRI occurred at the University of Rochester Medical Center and the University of California San Francisco Medical Center (January 2014 to May 2016). Patient eligibility criteria included primary life-limiting illness of metastatic cancer; English-speaking; older than 21 years; not having a documented exclusively comfort-oriented plan of care at the time of referral; and able to consent for research either directly or via health care proxy. Patient proxies were eligible if they were older than 21 years of age and English-speaking. All members of the interprofessional palliative care teams at both sites were eligible to participate. All participants (patients or proxies) signed written informed consent. Patients' family members or close friends who were present during the palliative care consultation provided verbal consent for the audio recording. No survey data were collected on patients' family members or close friends, unless they were the consented health care proxy for patients who lacked such capacity. In total, the PCCRI sample included 54 palliative clinicians and 231 patient or proxy participants contributing to a total of 363 recorded conversations. All conversations included palliative care clinicians, as well as patients and/or patients' family members or close friends (which may have included a health care proxy). We use the term “family” to include family, close friends, and health care proxies.
The initial consent for the parent PCCRI study allowed for subsequent analyses of the recorded conversations among the study team for research purposes; the current analysis of existing PCCRI data thus aligns with the aims of the parent PCCRI study and the original consent obtained. The Institutional Review Board at the University of Pennsylvania and the University of Vermont approved this analysis as exempt.
Data and measures
We analyzed transcripts of audio-recorded palliative care conversations and sociodemographic- and illness-related data acquired via self-report and the electronic health record from the parent PCCRI study. We also used the direct observation checklists (standardized lists to record environmental and conversational factors) and field notes (qualitative descriptions of any barriers to patient participation and impressions of key nonverbal interactions), completed by research observers in the parent PCCRI study, to help contextualize the palliative care conversations.
Prognosis communication strata
Prognosis communication was defined as any predictive statement about a future health-related event or status. 9 We created three strata of prognosis communication in the PCCRI sample based on the distribution of expressions of prognosis as identified by multiple trained human coders in previous PCCRI work (None: 0 prognosis expressions; Low: 1–3 prognosis expressions; High: ≥4 prognosis expressions). 20
Existential communication
Following the Conceptual Model of Existential Experience in Adults with Advanced cancer, 13 we defined existential communication as any discussion concerned with confronting mortality and the fragility of existence; in particular, relating to major themes of (1) time as a pressing boundary; (2) maintaining a coherent self; and (3) connecting with others. 21 In our previous work, we identified 11 typical topics of existential communication in conversations stemming from the PCCRI study (Appendix Table A1). 21 We used this previously developed codebook as an a priori coding scheme in the present study through the method of directed content analysis,22–24 while still being open to emergent codes (see Analytic Approach section).
Sampling
For the present study, we built on our previous work 21 where we analyzed a random subsample of conversations from the parent PCCRI study. 18 The initial sample size for the current study was informed by similar qualitative investigations of existential experience in adults with advanced cancer.25,26 We then stratified this random sample based on tertiles of prognosis communication (i.e., Prognosis Communication Strata). Subsequently, we purposefully sampled additional conversations within each strata to have a meaningful sample for subanalysis within and across strata (i.e., at least 10 participants per strata). 19 We continued sampling until meaning saturation 27 was achieved within each level of prognosis communication, 28 seeking a richly textured understanding of the dimensions of existential communication within each strata.
Analytic approach
We used within- and across-case analytic strategies to explore patterns of existential communication, comparing the intensity, frequency, and content, within and across conversations with none, low, and high levels of prognosis communication. 29 Within-conversations, we used a qualitative descriptive approach30,31 paired with directed content analysis.22–24 We considered the unit of analysis to be the conversation rather than the individual speaker, meaning we analyzed the contributions of patients, families, and clinicians to the dialog. We then categorized conversations according to intensity of expressions (mild, moderate, strong) related to existential experience. 32 Conversations were considered to have mild existential content if they had only few or passing expressions of existential experience, whereas conversations were considered to have strong existential content if they included many or strong expressions related to existential experience. Within- and across-levels of prognosis communication, we examined similarities and differences according to the intensity of existential communication and the content and frequency of codes. We used standard descriptive statistics to characterize our analytic sample. Given our small sample, we used nonparametric statistical tests to evaluate whether patient-level characteristics differed by prognosis communication level.
To maintain rigor, and bolster the trustworthiness of study findings,33,34 we engaged in the following strategies: (1) provided detailed descriptions of the context of original data collection, as well as selection and characteristics of study participants; (2) reviewed multiple data sources to provide a richer understanding of the phenomenon of interest (including direct observation checklists, field notes, and transcribed interviews); (3) kept analytic memos during the coding process creating an audit trail for review with the research team; and (4) the first author trained a research assistant to code the conversations and both analysts independently coded ∼20% of the conversation transcripts, meeting to discuss discrepancies, clarify the codebook, and reach consensus in the interpretation of existential communication.35,36
Results
The sample included 34 participants contributing to 45 palliative care conversations; patients participated in all but 3 conversations. Over half of patient participants identified as female (62%), two-thirds were younger than 70 years, the majority of participants identified as white (82%), and half of participants reported some financial insecurity (Table 1). There were no prominent differences in patient-level characteristics by prognosis communication level, including on measures of disease severity (i.e., Palliative Performance Scale [PPS] and time to death). Overall, our analyses of whether and how existential communication differed within and across conversations with none, low, and high levels of prognosis communication revealed two primary findings, detailed below.
Characteristics of Patient Participants by Prognosis Level (N = 34)
For statistical significance testing purposes, we used Fisher's exact test for categorical data and Kruskal–Wallis test for continuous data.
CRC, colorectal cancer.
More prognosis communication, more (and deeper) existential communication
First, we found that existential communication was more common, and more in-depth, within conversations with higher levels of prognosis communication. This was apparent through examining the distribution of the intensity of existential communication (Table 2) and existentially relevant codes (Table 3) by prognosis communication level.
Intensity of Expressions Related to Existential Experience by Prognosis Level
Conversations were considered to have mild existential content if they had few expressions or only passing expressions of existential experience, whereas conversations were considered to have strong existential content if they included many expressions or strong expressions related to existential experience.
Top 10 Codes by Levels of Prognosis Communication
This table represents the 10 codes which occurred most frequently within conversations grouped by prognosis communication level.
Denotes codes that contained existential expressions.
As Table 2 depicts, we found that the majority of conversations with no prognosis communication had mild existential communication, whereas all of the conversations in the high prognosis communication strata contained moderate or strong existential communication. Conversations with no prognosis communication contained few or passing expressions related to existential experience. For example, in one of these conversations, a discussion of being “tired” of all the “treatment stuff” led a family member (
This passing comment, that the patient feels she “can't do it anymore,” gave a sense that she was struggling with her current state of existence. Yet, the conversation did not linger on the existential; instead, pain and how to achieve relief became the focus of discussion. In contrast, in the high prognosis communication strata, conversations had more, and deeper, expressions related to existential experience. For instance, in one of these conversations, in answer to the palliative care clinician's (
This conversation then centered on what it felt like to be dying, and how the patient was making sense of his reality, feeling both “blessed” and “cheated.” The patient went on to explain, “And you say well, you shouldn't feel cheated because you had a lot of good times. Well, I feel cheated because I had a lot more planned out.” As this excerpt illustrates, conversations categorized as having strong existential communication were often sustained in their focus on the existential in contrast to conversations with no prognosis communication.
The distribution of existentially relevant codes across prognosis communication strata further demonstrates that existential communication was more common within conversations with higher levels of prognosis communication (Table 3). Across all three strata, rapport-building was prevalent (code: “connecting with care providers”). However, in conversations with higher levels of prognosis communication, existential topics featured more prominently, relating to concepts of time, “what matters most,” and seeking connection while struggling with feelings of being ultimately alone (corresponding codes: “time,” “what matters most,” and “with me versus by myself”). Conversely, in conversations containing no prognosis communication, much of the dialog focused on symptom assessment, symptom management, and navigating potential treatments (codes: “how are you feeling,” “helping that feeling,” and “exploring options”, respectively).
Existential versus physical focus
Second, we observed a shift in focus in conversations with higher levels of prognosis communication toward existential content and away from more physical focus of the patient's experience. This was apparent in the ways that participants discussed concepts of time, not knowing what to expect, and “what matters most.”
Time
Conversation regarding time was an ever-present feature in palliative care conversations. Patients and families reflected on the “good times” and “hard times” in their lives, questioned “how much time” they had, and wondered if it was the “right time” to transition to hospice. However, discussion of “time” was much more prominent in conversations with higher levels of prognosis communication (Table 3). In addition, as Table 4 reveals, the way individuals discussed time shifted in focus. “Time” captured discussion of medical time, related to the timing of hospital admissions, tests, and treatments, as well as how individuals described their existential time, a more personal timeline encompassing their past, present, and future experience with illness. As Table 4 illustrates, discussion of time was more medical in focus in conversations with no prognosis communication (e.g., time in relationship to treatments), while conversations with more prognosis communication emphasized existential time to a greater degree (e.g., time in relationship to existence, when it is “her time”).
Illustrative Quotes for Codes by Prognosis Level
Not knowing what to expect
In trying to figure out where they were in the course of their disease trajectory, and the timeline of their lives, participants expressed great uncertainty. “You never know,” “I have no way of knowing,” and “we will see how it goes,” were ubiquitous sentiments throughout conversations. While attempting to navigate this uncertainty together, clinicians expressed wishing that they “had this crystal ball working,” and patients and families articulated knowing that, unfortunately, “nobody has a crystal ball.” Yet, discussions of uncertainty related to different dimensions of not knowing across prognosis communication strata, revealing an existential shift in the focus of conversations with higher levels of prognosis communication (Table 4). In conversations with no discussion of prognosis, conversation related to prognostic uncertainty, feelings of uncertainty about daily life (e.g., when certain tests would take place), and symptom management (e.g., how much pain medication they would need). In conversations with higher levels of prognosis communication, the scope of uncertainty broadened from disease and symptom focused to include contemplation of existential uncertainty. These reflections ranged from not knowing whether or not they would survive, to wondering whether they would have time to achieve certain personal goals (like graduations and weddings of children and grandchildren), and ultimately, to questioning what dying would look like (e.g., “How am I going to die with this?”).
What matters most
Throughout palliative care conversations, patients, families, and clinicians discussed what is “most important” at this point. These goals, priorities, or “bucket list” items hinted at how a person defined their purpose and found meaning. Identifying “what matters most” also shaped the discussion of treatment preferences, given where a person was within their disease trajectory and their life. However, in conversations with no prognosis communication, discussion of “what matters most” happened less frequently than in conversations with higher levels of prognosis communication. In addition, as Table 4 shows, what was emphasized as most important shifted. Symptom management, and pain management specifically, was often identified as “what matters most” in conversations with no prognosis communication. This aligned with our findings that these conversations discussed symptom assessment and relief more frequently (Table 3). In conversations with higher levels of prognosis communication, “what matters most” was often more existential in nature (e.g., saying goodbye).
Discussion
This study adds to our understanding of the existential dimensions of prognosis communication in palliative care conversations with individuals with advanced cancer, their families, and palliative care clinicians. The findings build upon the existing literature on the relationship between prognosis communication and existential experience by highlighting key differences in palliative care conversations according to how frequently prognosis was discussed. Most notably, we found that conversations with more discussion of prognosis also contained more discussion of existential topics. This represented an existential shift in focus, from an emphasis on symptom management, and pain management specifically, in conversations with no prognosis communication to an emphasis on time and “what matters most” in conversations with more prognosis communication. These findings generate new directions for research and prompt immediate considerations for how we talk about prognosis in clinical practice.
Our work builds upon existing research investigating the relationship between prognosis communication and existential experience in two prominent ways. First, existing literature has reported a relationship between preference to discuss prognosis and awareness of prognosis with greater existential distress.10–12 While our findings revealed that in palliative care conversation with more prognosis communication, patients, families, and clinicians covered more and deeper existential ground, this did not necessarily represent greater existential distress. In fact, many patients and families described sources of joy, meaning, and peace in conversations with more prognosis communication. Second, our findings add evidence from the natural clinical setting to support Terror Management Theory (TMT). 37 TMT, derived from the work of Becker, 38 asserts that awareness of death (mortality salience) can provoke intense existential anxiety that individuals manage by embracing cultural worldviews. Our findings highlight that conversations related to prognosis may be recognized as mortality salience triggers, potentially prompting existential anxiety.15,37 This is important for clinicians to recognize when talking about prognosis, as navigating intense existential concerns, such as fear of dying, may make it challenging for patients and families to consider new information and reason effectively. 39
We also found that palliative care conversations with no discussion of prognosis contained a greater emphasis on symptom management, specifically pain. This finding aligns with previous work that pain relief is an important priority for individuals with cancer. 40 Given that pain affects more than two-thirds of patients with advanced cancer, 41 and approximately one-third of patients with cancer pain receive inadequate relief, 42 a focus on pain in palliative care conversations is unsurprising. Still, our findings add nuance to previous work. Our findings suggest that not only is physical symptom burden a pressing issue for individuals with advanced cancer in palliative care conversations, but it may need to be addressed before prognosis- or existential-related concerns can be considered.
There are several limitations of this research, which future investigations should seek to address. Our sample was an English-speaking, predominantly white group of patients receiving palliative care at two institutions, which may limit the transferability of findings to other institutions, specialties, or cultural contexts. Furthermore, we chose to stratify the sample into levels of prognosis communication based on frequency of communication and explore existential communication within and across levels. Future work taking into consideration depth of prognosis communication may be worthwhile. Finally, given the complex, interactional nature of palliative care conversations, we took an ecological approach to analysis and considered the conversation as the unit of analysis. Future research explicitly focusing on how clinicians respond to existential expressions 32 or patterns of interaction 43 may help to elucidate how these factors influence the arc of conversation.
Conclusion
Taken together, our findings add to the growing body of evidence highlighting prognosis communication as a key feature underlying the beneficial effects of palliative care1–3,8,9 by uncovering the salient existential dimensions of these conversations. This study supports the assertion that “planning [for the future] isn't just a practical task; it is an existential one.” 44 It is our hope that this study draws attention to the multiplicity and mutuality of concerns that arise when contemplating mortality and generates hypotheses for future study to advance the development of personalized communication strategies in palliative care.
Footnotes
Acknowledgments
The authors are grateful to the patients, family members, and palliative care clinicians who took part in the PCCRI study for their dedication to research devoted to enhancing the care of people with serious illness.
Authors' Contributions
Conception and design: all authors. Collection and assembly of data: R.G. Data analysis and interpretation: all authors. Article writing: all authors. Final approval of article: all authors.
Funding Information
This work was, in part, supported by the National Institutes of Health (NewCourtland Center for Transitions and Health institutional NIH/NINR T32NR009356 to E.C.T. and F31 Ruth L. Kirschstein NRSA F31NR018104 to E.G.B.), Sigma/Hospice and Palliative Nurses Foundation (End-of-Life Nursing Care Research Grant to E.C.T.), Rita and Alex Hillman Foundation (Hillman Scholars Program to E.G.B.), and American Cancer Society (Research Scholar Grant RSG PCSM124655 to R.G. to fund the PCCRI). The funding sources were not involved in study design, collection, analysis or interpretation of data, or writing of the report.
Author Disclosure Statement
No competing financial interests exist.
Coding Scheme
| Code name | Description of code | Illustrative quote |
|---|---|---|
| Setting up the conversation | Setting the stage for the conversation (e.g., introductions, introducing palliative care) | |
| My story | ||
| How things have been | Clinical history of illness course (e.g., events of the hospital stay) | |
| How I manage a | Psychological response to illness (e.g., regarding coping, adaptation, managing) | |
| Where things are right now | Illness understanding; where the illness is medically | |
| Where I am a | Discussion of where the person is (the self) on a timeline (of existence); includes discussion of mortality and awareness of dying and aging | |
| Why me? a | Questioning/offering an explanation of why this is happening (typically regarding severity of illness and/or dying) | |
| Living in a changing body | ||
| How are you feeling? | Discussion of symptoms (i.e., descriptions of how the illness has felt and the history of these feelings) | |
| Helping that feeling | Discussion related to attempting to find relief for symptoms (including history of management of symptoms) | |
| My body a | Statements that relate to what is happening in the person's body; may include reflections on loss of dignity, loss of control | |
| What I can and cannot do a | Related to discussion of capacities and ability to function (i.e., how illness affects daily living) | |
| Exploring options | ||
| Exploring options | Practical or logistical aspects of future treatment options (e.g., surgery, radiation, medications, resuscitation, ventilation) | |
| Getting home | Emphasis on home as an option and logistics of this choice (e.g., needing a hospital bed) | |
| Involving palliative care | Discussion of involving home palliative services/referral to the palliative care clinic, often includes description of what palliative care involves (and differentiation from hospice) | |
| Involving hospice | Discussion of involving hospice at home or comfort-directed care in the hospital (includes hospice logistics and philosophy) | |
| Weighing decisions | Discussion of approach to treatment decision making, often involving weighing of trade-offs (i.e., benefits and burdens of treatment), preferably use subcode | |
| Talking about talking about it | Talking about treatment decision making without getting into the actual decision making (e.g., emphasis on conversation being important, efforts not to engage) | |
| Taking time a | Taking pressure off of or expressing urgency in decision making; can also be the influence of time in decision making | |
| Readiness a | Includes discussion of not being ready previously and being ready now (or not) for treatment decisions (in relationship to hospice most of the time) | |
| Questions of choice a | Concerns about freedom to make a decision and the ability to take that decision back (often involves emphasis on control over future) | |
| Safety a | Concerns related to feeling safe in regard to treatment decisions (e.g., in certain settings, regarding medications) | |
| Connectedness and support a | Emphasis on the care and support (often relationally, through caregiving) that treatment (much of the time hospice) can provide; may also include concerns about not being supported (e.g., by family not being on the same page) | |
| Worth and waste a | Discussion of needs and repercussions of required by person/family in regard to a certain treatment (i.e., financial, caregiving), often leading to questions of is this (treatment) worth it? Includes consideration of doing “enough” versus “too much.” | |
| Previous experiences with death a | Reflections on past experiences with death (often includes details of loved ones' treatment trajectories) | |
| What I want and don't want | ||
| What I want and don't want | Discussion of preferences for treatments (regarding medications or surgeries, can be future treatments including end-of-life treatment preferences, may include preferences for place of death) | |
| What matters most a | Discussion of priorities and goals (overall or related to this hospital stay/specific treatment); these relate to the question of “what's most important” | |
| Wanting to die versus not wanting to die a | Discussion of when a person would want to die or is not ready to die yet (often related to evaluation of quality of life); may include discussion of a future self (related to when a person would want to die) | |
| Who I am | ||
| Tell me about you | Discussion of who a person is, outside of their status as a patient in the hospital; often occurs in taking a social history (assessing living situation, occupation, social supports, religious or cultural preferences) | |
| I am a | Related to how a person defines themselves (can be how a family member or a clinician understands the person); expression of a particular identity; can include discussion of who a person is not | |
| Looking back a | Reflecting back on life, including reminiscing and voicing regrets | |
| Relating to others | ||
| Relating to care providers | Mention of relationships with other care providers (for discussion of connection with care providers or feeling disconnected, use subcode) | |
| Connecting with care providers a | Attempts to align and establish rapport within the conversation (e.g., moments of humor); can also include reflections on connections with clinicians in the past | |
| Disconnected from care providers a | Rebukes to connection within the conversation (e.g., corrections; can include hospital interruptions); can also include discussion of frustrations with past providers | |
| My family and friends | Discussion of relationships with family and friends, including faith community (also includes pets) | |
| Worries about loved ones a | Discussion of challenges and concerns with relationships in the setting of serious illness; often, includes participants worrying about their loved ones after they die; can include fear of being a burden | |
| With me versus by myself a | Reflections on feeling connectedness versus isolation in relationships, a sense of community and belonging versus feeling alone; can include elements of legacy (i.e., connection with the next generation), may also include thinking about connection with God/nature and the afterlife (i.e., connection with loved ones in the next realm) | |
| Looking into the future | ||
| What to expect a | Related to conversations about the future (can include assessing information preferences for discussion about prognosis), includes questioning what is to come in terms of illness trajectory and treatment (use subcodes for specific projections) | |
| Direct projections | Related to discussion of the likely course and outcomes of disease (can include discussion of survival, i.e., longevity or cure, or quality of life like, i.e., symptoms and function) | |
| Process of dying a | Explicit discussion of the dying trajectory in terms of bodily function and changes (e.g., what happens in the body with cessation of eating and drinking) | |
| Not knowing what to expect a | Discussion related to not knowing what is going to occur in thinking about the future, includes questions of uncertainty | |
| Hopes a | Related to discussion of hopes and wishes for the future; can also include feelings of hopelessness (i.e., not knowing what to hope for, not having hope) | |
| Worries a | Related to discussion of concerns and worries that arise when looking into the future (separate code for worries about loved ones) | |
| How I manage looking into the future a | Discussion of psychological responses in dealing with the future (often related to managing uncertainty); includes information preferences as this is one way individuals manage looking ahead | |
| Time a | Discussion of time and timing in different ways; includes individuals situating themselves on a medical and existential timeline, which often involves discussion of having a shorter time and what they may go through for more time | |
| Strong emotions | Relates to when strong emotions are expressed (i.e., sadness/crying), including emotions that arise when talking explicitly about death and dying, as well as reflections that this is hard to talk about | |
Denotes a code which may contain discussion of existential experience
