|
Advertisement |
|
|
||
 |
|
|||||
|
|||||
|
 |
||||||
|
||||||
|
||||||
|
© 2003 American Society for Clinical Oncology Patients’ Perceptions of Quality of Life After Treatment for Early Prostate Cancer
From the Boston University School of Public Health; Boston University Medical School; Harvard Vanguard Medical Associates; Center for Outcomes Research, Massachusetts General Hospital Cancer Center, Massachusetts General Hospital; Harvard Medical School, Boston; Center for Health Quality, Outcomes, and Economic Research, Edith Nourse Rogers Memorial Veterans Hospital, Bedford, MA; Indiana University School of Medicine; Regenstrief Institute for Health Care, Indianapolis, IN; Veterans Affairs Medical Center, Washington, DC; Veterans Affairs Western New York Health Care System; and State University of New York at Buffalo Medical School, Buffalo, NY. Address reprint requests to Jack A. Clark, PhD, Department of Health Services, Boston University School of Public Health, 715 Albany St, T3-W, Boston, MA 02118; e-mail: jaclark{at}bu.edu.
Purpose: Treatment for early prostate cancer produces problematic physical side effects, but prior studies have found little influence on patients’ perceived health status. We examined psychosocial outcomes of treatment for early prostate cancer. Patients and Methods: Patients with previously treated prostate cancer and a reference group of men with a normal prostate-specific antigen (PSA) level and no history of prostate cancer completed questionnaires. Innovative scales assessed behavioral consequences of urinary dysfunction, sexuality, health worry, PSA concern, perceived cancer control, treatment decision making, decision regret, and cancer-related outlook. Urinary, bowel, and sexual dysfunction were assessed with symptom indexes; health status was assessed by the Physical and Mental Summaries of the Short Form (SF-12) Health Survey. Results: Compared with men without prostate cancer, prostate cancer patients reported greater urinary, bowel, and sexual dysfunction, but similar health status. They reported worse problems of urinary control, sexual intimacy and confidence, and masculinity, and greater PSA concern. Perceptions of cancer control and treatment decisions were positive, but varied by treatment: prostatectomy patients indicated the highest and observation patients indicated the lowest cancer control. Bowel and sexual dysfunction were associated with poorer sexual intimacy, masculinity, and perceived cancer control; masculinity and PSA concern were associated with greater confidence in treatment choice; and diminished sexual intimacy and less interest in PSA were associated with greater regret. Conclusion: The lack of change in global measures of health status after treatment for early prostate cancer obscures important influences in men’s lives; cancer diagnosis and treatment complications may result in complex outcomes. Aggressive treatment may confer confidence in cancer control, yet be countered by diminished intimate relationships and masculinity, which accompany sexual dysfunction.
PRESENTED WITH a diagnosis of early prostate cancer and with little reliable information on the efficacy of alternative treatments, most men decide to undergo active therapy, such as radical prostatectomy, external-beam radiotherapy, or brachytherapy. No active treatment modality has been shown to prolong life compared with initial observation or watchful waiting, although a recent interim analysis of a trial comparing radical prostatectomy and observation found a small benefit in prostate cancer–specific survival but not overall survival.1 However, all treatments carry significant risks of long-term side effects, including urinary, bowel, and sexual dysfunction, which alter and presumably diminish the quality of patients’ lives.2,3 The consequences of the treatment choice endure; since 1992, essentially all men with local or regional prostate cancer have survived at least 5 years. Observation defers possibly unnecessary treatment to avoid toxicity, and choosing one active treatment avoids the toxicity pattern of another. Thus, measuring quality of life influences of active treatment and observation is central to research on treatment effectiveness and for improved counseling of patients who must choose a treatment approach and then live with the consequences of their decision. Although the risks of urinary, bowel, and sexual dysfunction after different treatments are increasingly well characterized in outcomes research, the influence of such bodily dysfunction on the quality of prostate cancer survivors’ lives is not well characterized. Instead, a paradox has emerged. Treatment-related side effects, although often problematic to patients, do not appreciably change measures of overall health status or health-related quality of life.4–6 This unexpected result remains unexplained and little explored. The specific ways in which side effects of treatment are viewed and experienced by survivors of prostate cancer have not been examined carefully. Measures of prostate cancer–related quality of life have focused on the symptoms of side effects and ratings of how problematic the side effects are. However, when patients are asked to report the frequency and intensity of physical dysfunction, asking them further how much or how often specific symptoms or organ-specific symptom groups disturb or bother them may add little information. The correlations between the paired ratings of dysfunction and bother suggest they may reflect closely related perceptions.7 Moreover, questions about bother are rather nonspecific. Patients have not been asked about the behavioral, emotional, and interpersonal effects of physical dysfunction. Furthermore, previous research has not examined how men view these changes from the perspective of being a prostate cancer survivor. Investigators have not critically evaluated the effects of living with the diagnosis of prostate cancer on quality of life, including how surviving prostate cancer may entail accommodating the inherent uncertainty of the course of cancer, treated or untreated, and the potentially changing view of the choices one made when first confronted with the cancer diagnosis. We sought to probe more deeply the complex outcomes of treatment for early prostate cancer. We developed a patient-centered instrument to assess systematically men’s perceptions of treatment outcomes, focused on behavioral, interpersonal, and emotional changes that patients attributed to prostate cancer and its treatment.8 The instrument was designed to complement measures of symptomatic physical function.7,9,10 We began by undertaking focus groups with men who had initiated treatment for early prostate cancer 12 to 24 months previously. We asked these men about the ways their cancer and their treatment approach affected their lives, and explored the complex effects that these men attributed to physical changes. Through qualitative analysis of these wide-ranging discussions, we constructed scales to assess prostate cancer–related quality of life, perceptions of cancer control, and the perceived quality of treatment decisions. We report the results of a survey of quality of life after treatment for early prostate cancer and treatment-related urinary, bowel, and erectile dysfunction, as perceived by patients who had been treated for early prostate cancer, with comparisons to analogous perceptions of older male patients with no history of this disease. We address four questions. First, do patients who have undergone treatment for early prostate cancer differ from similar patients with no history of prostate cancer, with respect to quality of life? Second, do patients’ perceptions of their treatment decisions and the effectiveness of their treatment differ according to the treatment they chose? Third, to what extent are psychosocial dimensions of quality of life and perceptions of treatment effects related to measures of physical dysfunction associated with active treatment; that is, symptoms of urinary, bowel, and sexual dysfunction? Fourth, to what extent are patients’ perceptions of their treatment and its effectiveness related to the combined effects of urinary, bowel, and sexual dysfunction and prostate cancer–related quality of life?
Patients Computerized files were reviewed at three sites, a multispecialty, multisite group practice operating in the greater Boston area (pathology records and staging studies) and two Veterans Affairs medical centers in the eastern United States (clinical stage), to identify patients who had been treated for clinically staged early (T1–3, N0/X, M0/X) prostate cancer during the previous 12 to 48 months. These files were also reviewed to identify a reference group of patients who were randomly sampled from those who had received a prostate-specific antigen (PSA) test with a normal result (< 4.0 ng/mL) in the last 12 months and had no recorded history of prostate cancer. Lists of prospective patients were reviewed by their respective primary care physicians, who verified the diagnosis or its absence, identified patients who would be unduly stressed by a prostate cancer–related quality of life questionnaire, and granted permission to contact the remainder. A total of 70 patients were excluded as likely to be stressed: 26 with prostate cancer and 44 in the reference group. These patients were not significantly different from eligible respondents with respect to age or race. Questionnaires were mailed to 540 prostate cancer patients and 658 reference group patients in 1999. Follow-up mailings and telephone calls were used to maximize survey response. This study was approved by the institutional review boards of the Edith Nourse Rogers Memorial Veterans Hospital (Bedford, MA) and the three participating institutions.
Survey Questionnaire Prostate cancer–related quality of life was measured by multi-item scales that represent domains of quality of life in which patients, participating in focus groups, described effects they attributed to prostate cancer and its treatment. Details of the qualitative and subsequent psychometric analyses are presented elsewhere.8 The urinary control scale assessed problems of living with urinary dysfunction (eight items; eg, feelings of embarrassment, helplessness, preoccupation with need to urinate, limitations in activities). Four scales reflected discrete aspects of sexuality patients had articulated: sexual intimacy (seven items; eg, awkwardness and anxiety about initiating or completing intimate sexual activities), sexual confidence (four items; eg, comfort with one’s sexuality), marital affection (three items; eg, emotional distance from spouse or partner), and masculine self-esteem (eight items; eg, not feeling oneself a whole man, feeling weak and small). Two scales assessed misgivings about one’s health: health worry (six items; eg, apprehensiveness about what the doctor might find next, fear that changes will not be detected early) and PSA concern (two items; concern with monitoring and comfort in knowing one’s PSA). Four scales assessed perceptions of the treatment process and its effectiveness. Informed decision consisted of five items pertaining to the perceived quality of one’s treatment decisions (eg, had sufficient information, given a full explanation of likely effects, and satisfied with the choice). Decision regret included five items pertaining to feelings that one had chosen the wrong treatment, a wish to change the decision, or doubt about the value of any treatment. Cancer control was defined by five items referring to fear of recurrence or progression, as well as confidence that one’s cancer was under control. Outlook was defined by two items that assessed the perception that coping with cancer has made one stronger or resulted in a better outlook on life. Although the symptom indexes and the first seven quality-of-life scales were included in questionnaires completed by all respondents, the latter four scales pertaining to prostate cancer treatment and its effects were included only in those completed by prostate cancer patients. Reliability (Cronbach’s alpha) ranged from 0.77 to 0.93 for all but one scale; Cronbach’s alpha for PSA concern was 0.60. Quality-of-life scale scores were calculated by summing responses to the individual items and standardizing the sum to vary between 0 and 100. In contrast with the symptom indexes, high scores on most of the quality-of-life scales represented desirable quality of life. For example, high scores on urinary control indicated an ability to engage in activities freely, without risks of losing control or feeling frustrated or embarrassed by leakage; lower scores indicated greater feelings of risk and more frequent embarrassment. The exceptions were three scales for which a high score represented a perception with a negative valence: PSA concern, health worry, and regret. High scores on regret indicated strong misgivings about one’s choice of treatment and a counterfactual wish to change one’s mind. Primary treatment for early prostate cancer was assessed by patient report to ensure comparable and complete data for patients identified in different settings and, occasionally, for patients treated outside all three settings.11 Patients were asked whether they had undergone each of four treatments, including radical prostatectomy, external-beam radiation, brachytherapy, and cryosurgery, as well as deciding not to do anything for the time being (watch and wait). Patients who reported both radical prostatectomy and external-beam radiation were classified as undergoing radical prostatectomy, whereas those who reported brachytherapy and external-beam radiation were classified as having undergone brachytherapy. Patients were asked whether they had received neoadjuvant hormone treatment, were currently receiving hormone injections, or had received any other treatment, such as orchiectomy. General perceived health status was assessed by the SF-12 Physical and Mental Health Summary Scale, an abbreviated version of the widely used Medical Outcomes Study Short-Form Health Survey (SF-36), which accurately produces Physical and Mental Component Summary scores, normalized to the adult US population (mean, 50; standard deviation, 10).12 Coexistent disease was assessed by asking the patient whether a doctor had ever told him that he had any of 16 chronic diseases, which were aggregated as five indicators (lung, heart, neurologic disease, arthritis, or diabetes) and then summed to an index.
Statistical Analysis To address the relationships between psychosocial quality of life and urinary, bowel, and sexual dysfunction, we estimated ordinary least squares regression models to evaluate the associations between the symptom indexes, considered jointly, and the quality-of-life and treatment effects scales. For the regret scale, we estimated a logistic regression model. Type of treatment, age, coexistent disease, and system of care were included as covariates in all models. Finally, we estimated a second series of regression models, with cancer control, informed decision, and outlook as the dependent variables, and a logistic regression model for regret. Each of these outcome variables was regressed on the four symptom indexes and the seven quality-of-life scales, along with type of treatment, age, coexistent disease, and site of care. This last set of models was estimated using a backward selection procedure, variables with minimally significant coefficients were retained (P < .10).
Questionnaires were returned by 349 of 540 (65%) of the prostate cancer patients and 398 of 658 (60%) of the reference group. Respondents and nonrespondents were compared with respect to age and did not differ. One third of the prostate cancer patients were African-American, 69% were high school graduates, and 60% were married, with an additional 14% reporting a partner who was like a spouse (Table 1  ). Prostate cancer patients were somewhat older, on average, than the reference group: 71 v 67 years old (P < .001). Otherwise, the two groups did not differ substantially with respect to demographic characteristics and coexistent disease. Nearly equal numbers of prostate cancer patients reported undergoing radical prostatectomy (17 of 131 patients also received external-beam radiation) or external-beam radiation (130 patients), and 16 patients said they received brachytherapy (three of whom also received external-beam radiation). Observation was reported by 30 patients and hormonal therapy was reported by 27 patients, whereas type of treatment was not reported by 15 respondents.
Prostate Cancer–Related Quality of Life Patients treated for early prostate cancer were indistinguishable from the reference group with respect to overall physical and mental health (Table 2 ). However, prostate cancer patients reported greater urinary incontinence, urinary obstruction or irritation, bowel dysfunction, and sexual dysfunction. Symptom index scores were associated with treatment in previously documented patterns of side effects; urinary incontinence and sexual dysfunction were higher among patients who had undergone radical prostatectomy, whereas urinary obstruction or irritation and bowel dysfunction were higher among recipients of radiation therapy.16,17
Despite their similarity on global measures, prostate cancer patients differed from the reference patients on five of the seven prostate cancer–focused quality-of-life scales. Patients who had undergone surgery or radiation therapy reported significantly worse quality of life with respect to urinary control. Patients who had undergone surgery or radiation also reported significantly lower sexual intimacy and sexual confidence. Relative to patients with no history of prostate cancer, patients who had undergone surgery or radiation reported disruption and frustration attributed to problems with urinary control. They also tended to report greater awkwardness and anxiety about sexual interaction and intimacy, and less self-confidence regarding their sexual feelings and capability. However, among men who said they either were married or had a partner who was like a spouse, treatment for prostate cancer was not associated with perceptions of diminished marital intimacy. Nevertheless, experience with prostate cancer was associated with lower scores on masculine self-esteem, particularly among men who had undergone radical prostatectomy and those who had opted for watchful waiting. Apprehensiveness about worsening health problems was not significantly greater among prostate cancer patients as a group, although health worry scores were slightly greater among radiotherapy and watchful waiting patients, relative to surgery patients. Not surprisingly, men with the diagnosis of prostate cancer expressed substantially greater concern with their PSA level, irrespective of treatment approach.
Perceived Effects of Treatment Perceived cancer control varied by treatment group. Radical prostatectomy patients reported relatively high levels of confidence about cancer control, whereas those who had chosen watchful waiting were less confident. Watchful waiting patients were also less satisfied with their decision making, yet also less regretful, although the differences were not statistically significant. Neither regret nor outlook varied significantly by treatment, although the small number of hormone ablation patients indicated that they were somewhat more regretful and expressed a less positive outlook.
Relationships Among Outcomes
The joint effects of treatment, symptom severity, and quality of life on cancer control, informed decision, regret, and outlook are shown in Table 4 . Confidence that one’s cancer is in control was lower in patients expressing greater apprehensiveness about their health. Perceived cancer control was also associated with treatment, and was higher with the aggressive surgical approach and lower with hormone therapy (a noncurative approach). Cancer control was also positively associated with scores on sexual intimacy and masculinity. Belief that the decision-making process was well informed was positively associated with self-appraised masculinity and with the reassurance offered by knowing one’s PSA. Conversely, regret increased with increased health worry, but was less likely the greater one’s PSA concern. Regret decreased as the quality of sexual intimacy increased. Finally, overall cancer-related outlook (ie, a perception of oneself as having coped well with cancer) was greater among patients who had undergone radical prostatectomy, but was negatively associated with sexual dysfunction. Improved outlook was correlated with greater masculine self-esteem and concern with PSA.
Numerous studies, using patient-based methods, have documented the incidence and severity of urinary, bowel, and sexual dysfunction after alternative active treatments. As a result, men have better information about the consequences of alternative treatments among which they must choose. However, most research on the outcomes of treatment for prostate cancer has emphasized the direct physical effects of treatment. These outcomes are no doubt important to patients, but they draw an incomplete picture. Our findings, which are based on patient-centered measures derived from men’s accounts of their lives with prostate cancer, suggest additional, complex psychosocial outcomes. Quality of life after diagnosis and treatment for early prostate cancer encompasses changes in how men live with compromised urinary, bowel, and sexual function; changes in how they view their capabilities and themselves; and their persistent uncertainty about their cancer and the treatment choices they were asked to make. We have explored new dimensions of prostate cancer–related quality of life. Our data are limited, certainly. They are based on a cross-sectional survey of previously treated patients, with hormone therapy and observation represented by small patient numbers, and hence with limited power for comparisons with other treatment approaches. Differences between prostate cancer patients and the reference group suggest changes that need to be evaluated prospectively to determine the effects of treatment decisions, physical side effects, and the achievement of cancer control. Moreover, they suggest the need to understand how the receipt of a diagnosis and the knowledge that one has prostate cancer may frame a man’s perceptions of bodily function and the quality of his life. These psychosocial outcomes may highlight the effects of prior health and physical function, patient’s expectations, personal background, social resources, and patient’s ongoing relationships with his physicians on his subsequent quality of life. Consistent with previous studies, we found that treatment for prostate cancer was associated with increased urinary, bowel, and sexual dysfunction, but not with decrements in overall functional status and well-being.4–6 When we probed the influence of treatment on quality of life, marked differences between prostate cancer patients and comparable men who do not have prostate cancer became clear. We found that urinary incontinence was associated in prostate cancer patients with complex problems, including preoccupation with avoiding leakage and the location of bathrooms, and feeling dirty, helpless, and embarrassed when control is lost. We found that bowel dysfunction was associated with multiple quality-of-life effects. We found decrements in sexual quality of life related to prostate cancer that emanated well beyond erectile dysfunction. When given opportunities in focus groups, prostate cancer patients explained at length that after prostate cancer their sexuality changed much more than in physical impairments; it included misgivings about their ability to perform sexually, anxiety about intimacy, wariness in their relationships with women, disquieting loss of pleasing fantasies, and diminished masculine self-concept.18 Our survey data confirm that prostate cancer is associated with decrements with respect to sexual intimacy, confidence, and masculinity that transcend erectile dysfunction. Prostate cancer–related quality of life also encompasses patients’ confidence that their prostate cancer is controlled and that they made a well-informed decision in choosing a course of treatment. Most of the survey respondents felt positively about their treatment and its effectiveness, although a substantial minority reported persistent misgivings about their cancer and their treatment choices. Other studies have addressed patient satisfaction with treatment, often concluding that most are satisfied.4,19,20–23 When patients have been asked whether they would make the same decision again, 90% or more have indicated that they would.19,21,22 Nonetheless, patients may recall unsatisfactory experiences reaching treatment decisions. In a survey of urologists and members of a national prostate cancer survivors support group, Crawford et al24 found that most patients recall receiving much less information about treatment alternatives and their outcomes than physicians say they typically provide. In the patients we surveyed, 24% said their treatment decisions were poorly informed and 16% expressed regret; that is, they felt they were living with a poor choice and wished they could change the course they had pursued. One third indicated little confidence that their prostate cancer was controlled. Our attempt to understand better the experience of men after the diagnosis of and choice of treatment for prostate cancer has identified both previously unappreciated changes and some ways they may interact. In the absence of definitive guidance from medical research on the benefits of treatments or on how their own approach will affect them in the first years after treatment, men acknowledge their burden of symptoms, but obviously look beyond them in evaluating their choices. Men who chose the aggressive surgical approach report greater urinary incontinence and sexual dysfunction, but report the influence of incontinence on their lives as being no different from that reported by radiation therapy patients, who report much less incontinence. Those who chose surgery are also more confident that their treatment succeeded, and report greater perceived cancer control, which is the primary goal of treatment. Men may adapt to new dysfunction by emphasizing what has not been lost: despite greater levels of sexual dysfunction and lower levels of sexual intimacy and sexual confidence, men treated with radical prostatectomy and radiation therapy report marital affection scores no different from those of men without cancer we surveyed. There may be a complex price paid for not choosing active treatment, despite the knowledge that treatment complications have been avoided and the uncertain efficacy of active treatment. The relatively few men who chose initial observation recorded fewer symptoms than actively treated men for nearly all physical function and quality-of-life domains, but reported the least confidence in their cancer control and, surprisingly, lower belief that their decision was informed. However, they also tended to report less regret, perhaps indicating both an appropriate awareness of having bypassed antitumor treatment and satisfaction with the choice. Perceptions of cancer control and the quality of one’s treatment decisions are correlated with how patients view their quality of life. Although men, when faced with choosing a treatment, may trade quality of life to achieve a better chance at cure or control, these competing objectives may become aligned over time, as perceiving cancer control increases along with their capacity for sexual intimacy and their masculinity, or vice versa. Greater masculine self-esteem was associated with the conviction that a well-informed decision was made. However, confidence in one’s decision may be better preserved by a focus on the reassuring numerical precision of one’s PSA, especially the usually reassuring results soon after treatment, rather than revisiting the uncertainty surrounding the initial treatment decision, possibly with regret. Confidence with respect to cancer control and the wisdom of one’s decisions may remain provisional. These results do not resolve the apparent paradox that many patients report new, troublesome sexual, urinary, and bowel symptoms after treatment but infrequently report lower overall health-related quality of life as a result, but they may indicate a new, potentially rewarding line of inquiry. Treatment-related symptoms burden men, but unlike local or systemic symptoms that denote a tumor’s progression toward the patient’s death, they signal a diminished quality of life but not foreshortened survival. Evaluating them requires assessing the impact on life, not health. Furthermore, these results shed some important new light on why few men report they regret their decisions regardless of outcomes. Men may have mentally exchanged the risk of symptoms for perceived better efficacy, or have accepted lesser efficacy to avoid symptoms. They may compartmentalize their concerns: cancer patients reported no different health worry, but much greater PSA concern than reported by noncancer control patients. Furthermore, although we did not address this possibility directly in this study, men may consider only cancer and not the effects of treatment as their health problem, rendering treatment-related influences inadmissible when questions are asked about a patient’s health. Our findings suggest issues for clinicians to explore with their patients who are either dealing with a diagnosis of early prostate cancer and deciding on treatment or are living with the outcomes of their decisions. The diagnosis of early prostate cancer presents a substantial challenge to patients. How they respond to the challenge, including the treatment they choose, could change the quality of their lives. Information about these psychosocial outcomes may help clinicians in counseling their patients in reaching satisfying treatment decisions. Discussing how bothersome or distressing the side effects of treatment can be enables a more expansive exploration of the influences of treatment on men’s lives, but a rather imprecise one. Although additional research is needed to determine the clinical significance of scores on the measures we have developed, we have meanwhile defined some lines of inquiry that clinicians may pursue in addressing issues that matter to their patients. They may help to anticipate more fully the effects of treatment and then later deal with them. By appreciating the complex changes that may ensue with diagnosis and treatment, clinicians can help patients recognize misperceptions, manage their losses, and feel more confident about the courses they have pursued. The process of choosing the best treatment approach for early prostate cancer is extraordinarily complex. Although the additional dimensions of the experience we have identified make it no less so, we hope considering them will allow patients to make decisions that more thoroughly reflect the choices they face and help them make decisions they can live with more comfortably. We also hope the additional dimensions of patients’ experiences will more usefully recast the policy debate about the competing options for early prostate cancer.
The authors indicated no potential conflicts of interest.
Supported by Health Services Research and Development Service Grant ECV-97081-1 from the Department of Veterans Affairs. The views expressed in this article are those of the authors and do not necessarily represent the views of the Department of Veterans Affairs.
1. Holmberg L, Bill-Axelson A, Helgesen F, et al: A randomized trial comparing radical prostatectomy with watchful waiting in early prostate cancer. N Engl J Med 347:781–789, 2002
2. Wasson J, Cushman C, Bruskewitz R, et al: A structured literature review of treatment for localized prostate cancer. Arch Fam Med 2:487–493, 1993 3. Altwein J, Ekman P, Barry M, et al: How is quality of life in prostate cancer patients influenced by modern treatment? The Wallenberg Symposium. Urology 49:66–76, 1997 (suppl 4A)[CrossRef][Medline]
4. Litwin M, Hays R, Fink A, et al: Quality-of-life outcomes in men treated for localized prostate cancer. JAMA 273:129–135, 1995
5. Madalinska J, Essink-Bot M, deKoning H, et al: Health-related quality of life effects of radical prostatectomy and primary radiotherapy for screen-detected or clinically diagnosed localized prostate cancer. J Clin Oncol 19:1619–1628, 2001 6. Clark J, Rieker P, Propert K, et al: Changes in quality of life following treatment for early prostate cancer. Urology 53:161–168, 1999[CrossRef][Medline] 7. Clark J, Talcott J: Symptom indexes to assess outcomes of treatment for early prostate cancer. Med Care 39:1118–1130, 2001[CrossRef][Medline] 8. Clark J, Bokhour B, Inui T, et al: Measuring patients’ perceptions of the outcomes of treatment for early prostate cancer. Med Care 41:923–936, 2003[CrossRef][Medline] 9. Litwin M, Hays R, Fink A, et al: The UCLA Prostate Cancer Index: Development, reliability, and validity of a health-related quality of life measure. Med Care 36:1002–1012, 1998[CrossRef][Medline] 10. Wei J, Dunn R, Litwin M, et al: Development and validation of the expanded prostate cancer index composite (EPIC) for comprehensive assessment of health-related quality of life in men with prostate cancer. Urology 56:899–905, 2000[CrossRef][Medline]
11. Clegg L, Potosky A, Harlan L, et al: Reference of self-reported initial treatment with medical records: Results from the Prostate Cancer Outcomes Study. Am J Epidemiol 154:582–587, 2001 12. Ware J, Kosinski M, Keller S: A 12-item short-form health survey: construction of scales and preliminary tests of reliability and validity. Med Care 34:220–233, 1996[CrossRef][Medline]
13. Kazis L, Miller D, Clark J, et al: Health related quality of life in VA patients: Results from the Veterans Health Study. Arch Intern Med 158:626–632, 1998
14. Kazis L, Ren X, Lee A, et al: Health status in VA patients: Results from the Veterans Health Study. Am J Med Qual 14:28–38, 1999 15. Dunnett C: A multiple references procedure for comparing several treatments with a control. J Am Stat Assoc 50:1096–1121, 1955[CrossRef]
16. Stanford J, Feng Z, Hamilton A, et al: Urinary and sexual function after radical prostatectomy for clinically localized prostate cancer: The Prostate Cancer Outcomes Study. JAMA 283:354–360, 2000
17. Hamilton A, Stanford J, Gilliland F, et al: Health outcomes after external-beam radiation therapy for clinically localized prostate cancer: Results from the Prostate Cancer Outcomes Study. J Clin Oncol 19:2517–2526, 2001 18. Bokhour J, Clark J, Inui T, et al: Sexuality after treatment for early prostate cancer: Exploring the meanings of "erectile dysfunction." J Gen Intern Med 16:649–655, 2001[CrossRef][Medline] 19. Fowler FJ Jr, Barry MJ, Lu-Yao G, et al: Outcomes of external-beam radiation therapy for prostate cancer: A study of Medicare beneficiaries in three surveillance, epidemiology, and end results areas. J Clin Oncol 14:2258–2265, 1996[Abstract] 20. Demark-Wahnefried W, Schildkraut J, Iselin C, et al: Treatment options, selection, and satisfaction among African American and white men with prostate carcinoma in North Carolina. Cancer 83:320–330, 1998[CrossRef][Medline]
21. Potosky A, Legler J, Albertsen P, et al: Health outcomes after prostatectomy or radiotherapy for prostate cancer: Results from the prostate cancer outcomes study. J Natl Cancer Inst 92:1582–1592, 2000
22. Potosky A, Reeve B, Clegg L, et al: Quality of life following localized prostate cancer treated initially with androgen deprivation therapy or no therapy. J Natl Cancer Inst 94:430–437, 2002 23. Carvalhal G, Smith D, Ramos C, et al: Correlates of dissatisfaction with treatment in patients with prostate cancer diagnosed through screening. J Urol 162:113–118, 1999[CrossRef][Medline] 24. Crawford D, Bennett C, Stone N, et al: Comparison of perspectives on prostate cancer: Analyses of survey data. Urology 50:366–372, 1997[CrossRef][Medline] Submitted February 21, 2003; accepted August 4, 2003.
This article has been cited by other articles:
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
|
|||||||||||
|
|||||||||||
|
|
Copyright © 2003 by the American Society of Clinical Oncology, Online ISSN: 1527-7755. Print ISSN: 0732-183X
|
TOP
ABSTRACT
INTRODUCTION
40, reflecting a tendency to endorse expressions of regret as at least somewhat true, were considered indicative of being regretful. The treatment groups were then compared with respect to the relative frequency of being regretful, using the logistic model to estimate relative frequencies, adjusted for the effects of age, coexistent disease, and site of care. 
