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A Randomized Controlled Trial of Shared Decision Making for Prostate Cancer Screening
Robert J. Volk, PhD;
Alvah R. Cass, MD, SM;
Stephen J. Spann, MD
Arch Fam Med. 1999;8:333-340.
ABSTRACT
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Objective To evaluate a patient-educational approach to shared decision making for prostate cancer screening.
Design Randomized controlled trial with preoffice visit assessment and 2-week follow-up.
Setting University-based family practice center.
Patients Men aged 45 through 70 years with no history of prostate cancer or treatment for prostate disease (N=160). Two patients were unavailable for follow-up.
Intervention Twenty-minute educational videotape on advantages and disadvantages of prostate-specific antigen (PSA) screening for prostate cancer.
Main Outcome Measures A measure of patients' core knowledge of prostate cancer developed for this study, reported preferences for PSA testing, and ratings of the videotape.
Results Patients' core knowledge at baseline was poor. At 2-week follow-up, subjects undergoing videotape intervention showed a 78% improvement in the number of knowledge questions answered correctly (P=.001), and knowledge increased about mortality due to early-stage prostate cancer, PSA screening performance, treatment-related complications, and disadvantages of screening. No overall change was observed for control subjects. At follow-up, 48 (62%) of 78 intervention patients planned to have the PSA test compared with 64 (80%) of 80 control patients (18.5% absolute reduction; 95% confidence interval, 4.6%-32.4%; P=.009). Intervention subjects rated favorably the amount of information provided and the clarity, balance, and length of the videotape and would recommend the videotape to others.
Conclusions Patient education regarding the potential benefits and harms of early detection of prostate cancer can lead to more informed decision making. Incorporating the PSA videotape into the periodic health examination for asymptomatic men aged 50 years and older is recommended.
INTRODUCTION
FOR MEN, prostate cancer is the most common noncutaneous cancer and the second leading cause of death due to cancer. Although prostate cancer is often curable when detected at an early stage, the recommendations from professional organizations remain inconsistent regarding the routine use of serum tumor markers (prostate-specific antigen [PSA]) for prostate cancer screening in asymptomatic men.1-2 The argument against PSA screening in asymptomatic men is summarized as follows: clinically localized prostate cancer progresses slowly, and most men with prostate cancer will die of other causes; PSA testing identifies cancers that may never become problematic; we have no randomized clinical trial data to show that screening for prostate cancer decreases mortality due to this disease; and treatment for prostate cancer carries risks, including erectile dysfunction and incontinence.3-6 Prostate cancer screening is considered a "utility-sensitive decision"7 because the benefits of early detection are uncertain, and men's preferences for the outcomes of treatment are central to determining the optimal screening strategy.6, 8-9
Given the uncertainty surrounding the question of prostate cancer screening, many investigators have argued for actively involving the patient in the decision-making process.6, 8-12 Recently, the American College of Physicians issued a clinical guideline for screening for prostate cancer that called for educating patients about the benefits and harms of early detection and treatment, and thus individualizing the decision.5 However, the question remains how to best involve patients in decision making about prostate cancer screening. One such approach pioneered by Albert Mulley, MD, MPP, and John Wennberg, MD, MPH, is "shared decision making."13-14 The shared decision-making approach challenges the assumption that many medical decisions are too complex and that patients are too ignorant to make appropriate decisions about their treatment.15 Educational video products have been developed that strive for a balanced presentation of relevant facts using patient testimonials and information about the consequences of treatment and that emphasize the importance of patients' values in making choices about screening and treatment.16
Our study is a randomized controlled trial to evaluate a patient-educational, shared decision-making approach to prostate cancer screening in asymptomatic primary care patients. We independently evaluated the videotape, The PSA Decision: What YOU Should Know, developed by The Foundation for Informed Medical Decision Making, Inc, Hanover, NH, as part of its Shared Decision-Making programs. The videotape is used with permission of the Foundation. We hypothesized that primary care patients who viewed the videotape would demonstrate improved core knowledge regarding epidemiology of prostate cancer, screening accuracy, treatment effectiveness, and treatment complications, compared with control patients. We hypothesized further that fewer patients would prefer PSA testing after viewing the videotape, compared with control subjects. This latter hypothesis is based on the assumption that most men would prefer to have the PSA test if offered by their physicians and on the attention given to PSA testing in the popular media. Other objectives were to evaluate patients' impressions of the videotaped presentation and to relate stated preferences for PSA testing to patients' utility assessment concerning complications of prostate cancer treatment.
SUBJECTS AND METHODS
PROTOCOL
Study Site and Subjects
The site for our study was the University of Texas Medical Branch Family Medicine Center, Galveston, Tex, a university-based family medicine clinic. The clinic's annual patient volume exceeds 30,000 and includes resident and faculty practices. The community served is multiethnic, with a large representation of African Americans and Mexican Americans. The patient base is diverse socioeconomically, with 18.6% covered by Medicare; 24.6%, Medicaid; and 38.1%, managed care or private insurance. The remaining 18.7% are uninsured (self-paying).
Subjects for this study included men aged 45 through 70 years, with no history of prostate cancer, who presented for care at the Family Medicine Center. We did not exclude patients with urinary incontinence or erectile dysfunction, because these patients are appropriate candidates for prostate cancer screening, and their preferences for screening may differ from those of other patients.
Intervention Group
Our intervention consisted of an educational videotape and an accompanying brochure on the risks and benefits of PSA testing for prostate cancer in men aged 50 years or older and in good overall health. In the videotape, 2 physicians assume the role of patients, 1 favoring regular PSA testing and the other opposing it. Epidemiology of prostate cancer, accuracy of the PSA test, and complications associated with treatment of prostate cancer are discussed. In addition, a man with prostate cancer describes his experience with expectant management (watchful waiting). The videotape is 20 minutes long and is meant to be viewed before an office visit (as in our study) or in a patient's home. The brochure includes many of the tables found in the videotape, along with a summary of the advantages and disadvantages of screening.
Control Group
Subjects assigned to the control group of the study received no intervention before their office visits. After completing the 2-week follow-up assessment, we mailed an educational brochure to these patients because they wanted more information about PSA testing.
Procedures
Subjects were enrolled during the 5 months from February 1 through June 30, 1997. Appointment lists for the clinic were reviewed to identify male family medicine patients. The computerized patient record was then reviewed to select additional men aged 45 to 70 years with no history of prostate cancer. Qualifying patients were contacted by telephone several days before their scheduled office visit and invited to participate in the study. Of the 209 patients contacted initially, 24 refused to participate, and an additional 25 were not eligible for reasons of chronic disabling physical illness, incorrect patient records about a history of prostate cancer, and cognitive impairment precluding participation. Those eligible and willing to participate were asked to arrive 30 to 45 minutes before their office visits to complete the study questionnaire.
Patients were assigned randomly to 1 of the following 3 study groups: videotape intervention followed by a utility assessment (n=40), videotape intervention alone (n=40), and control (n=80). The utility assessment provided an additional test of the validity of the videotape intervention. Because the utility assessment may have led to increased knowledge about prostate cancer, half of the intervention subjects did not receive the utility assessment, thus allowing us to examine the effect of the assessment.
Participants completed self-report questionnaires before their scheduled office visits (baseline phase). Sociodemographic indicators, family history of cancer (including prostate), previous PSA testing, preference for having a PSA test, and our knowledge measures were included.
After the office visit, subjects in the intervention groups completed a postvisit assessment, including a rating of the videotape presentation. Subjects in the first group also completed a utility assessment to determine their preferences for outcomes of treatment for prostate cancer (4 patients did not complete the utility assessment because they could not remain after their visits).
Telephoned follow-up assessments were conducted at 2 weeks after the baseline assessment and intervention. The same knowledge measure was administered at follow-up. All study questionnaire and interview materials were translated into Spanish and backtranslated into English, and Spanish-speaking interviewers were used. (Four patients selected translated materials.) The study was approved by the institutional review board for use of human subjects. Each subject received $20 as reimbursement for participating.
Outcome Measures
We developed a new measure of prostate cancer knowledge for this study. Core domains of prostate cancer knowledge were identified, including epidemiology, screening accuracy, treatment effectiveness, and treatment-related complications. A multiple-choice response format was adopted (with 3 options), following formats used in similar studies of patient education about prostate cancer screening. We then reviewed the PSA videotape and the accompanying brochure and developed 16 items for the test set. Items were reviewed by the project investigators and peer faculty for content validity, readability, and consistency in use of terms. Item order was randomized, as was the order of the correct responses among the options. We administered the test set in a pilot sample of 24 male family medicine patients.
Using patients' responses in the pilot, we identified 4 pairs of items where cueing may have been a concern (ie, item content was similar, and the response to 1 item in the pair suggested the correct response to the second item) and 2 items that included terms most patients did not understand. We also noted missing data rates of 25% through 45%. These were a result of patients refusing to answer a question if they did not have at least some inclination of the correct response. Therefore, the next version of the measure included the response option "I don't know enough to guess." The revised, 10-item version was administered to a second sample of 23 male family medicine patients. Response patterns proved acceptable in this revised version, which was written at a fifth-grade reading level.
Subjects' preferences for PSA testing were measured by responses to the question "Given what you know about prostate cancer and PSA testing, would you choose to have a PSA test?" with response options of "yes," "no," and "I'm not sure." This question was included in the baseline questionnaire and in the 2-week follow-up assessment.
Subjects in the intervention groups were asked to rate the PSA videotape on the amount of information provided, length of the tape, clarity of the presentation, and balance of the presentation for or against screening. These indicators have been used in previous shared decision-making intervention studies.11 At the 2-week follow-up assessment, subjects in the intervention groups were asked the degree to which their preferences for PSA testing were influenced by the videotape and whether they would recommend it to other patients.
We performed the utility assessment on subjects in the first intervention group for various complications of prostate cancer treatment, including incontinence, erectile dysfunction, urethral stricture, and rectal injury. A utility is the fractional proportion of a year in perfect health, which is equivalent to a year with the treatment complication.17 The methods used to elicit utilities were category scaling, where the subject ranks outcome states on a scale from 0 (death) to 100 (perfect health), and time trade-off, where an indifference point is determined between normal life expectancy in the compromised health state (eg, incontinent) or less time in perfect health.17
ASSIGNMENT
Patients were randomized individually after eligibility had been determined. Randomization by permuted blocks was used to assign patients to ensure balanced numbers of subjects in each study group. Each block included the numbers 1 through 4, where 1 was the videotape (intervention) and utility assessment group, 2 was the intervention only group, and 3 and 4 were control groups (we anticipated that groups 1 and 2 would be collapsed in the primary analyses). Blocks were developed for all possible permutations of the numbers 1 through 4. Blocks were then selected at random and used to determine the order of assignment to study group as patients entered the study. Neither the subjects nor the interviewers were blinded to the treatment assignment.
MASKING
Blinding patients to the assignment was not possible in this study. Physician providers were not notified of patients' intervention assignment. Interviewers conducting the 2-week follow-up were not blinded to the patient assignment, because several interview questions specifically addressed the videotape.
DATA ANALYSES
The intervention only and intervention plus utility assessment groups were compared on sociodemographic indicators, previous PSA testing, and all outcome measures. Both groups did not differ significantly on any indicators and were subsequently collapsed for further analyses. The intervention and control subjects were compared on sociodemographic indicators and previous PSA testing. Results of  2 analysis were used for all categorical indicators, and t tests were used for continuous indicators.
There was no need to perform the outcome analyses based on intention to treat, because all intervention patients viewed the entire videotape. The average number of questions answered correctly on the knowledge questionnaire was the primary knowledge outcome variable. These data were not normally distributed. The Wilcoxon signed rank test18 was used to test for differences in knowledge before and after the intervention for both groups. The percentage of correct responses to specific knowledge questions was reported also. With 80 subjects in each group, statistical power was greater than 80% to detect a change in knowledge scale scores of less than 0.50 (ie, <1 additional question answered correctly), assuming a type I error rate of less than .05 1-tailed, and standard deviation of the change scores of 2.0 (power analysis includes adjustment for Wilcoxon test).19
The proportions of subjects preferring the PSA test before and after intervention were compared using contingency tables with the McNemar change test.18 A difference between the intervention and control subjects in preference for PSA testing of 10% to 15% could be detected with 80% power, assuming a type I error rate of less than .05 1-tailed, and 80% of subjects in the control group would prefer to have the test.19 Supplementary analyses were performed to test the effect of family history of prostate cancer on screening preferences at the 2-week follow-up for each group. The relationship between reported past PSA testing and preference for PSA testing at the 2-week follow-up was compared further for both groups. Adapting the number needed to treat concept,20 we determined how many patients would need to view the videotape for 1 additional patient to decide about screening in the direction we observed in our study. In this case, we report the number needed to view the videotape for 1 additional patient to opt against PSA testing. Ratings of the PSA videotape were reported as percentages. Utility values were compared for patients who preferred to have the PSA test and for patients who did not prefer to have the test or who were indifferent, using the Mann-Whitney U test.18 Data were analyzed using SPSS for Windows.21
RESULTS
PARTICIPANT FLOW AND FOLLOW-UP
The flow diagram for the study can be found in Figure 1. Baseline data were collected around scheduled office visits to the Family Medicine Center. Randomization occurred after eligibility was assessed. Patients completed the baseline questionnaire before seeing their providers. Patients in the intervention group viewed the PSA videotape before seeing their providers, and then completed an assessment of the videotape after their office visit but before leaving the clinic. Those patients in the intervention plus utility assessment group remained after their visits to complete the utility assessment, which averaged 30 minutes in duration. The 2-week follow-up interview, which included readministration of the knowledge questionnaire and questions on PSA testing, was conducted by telephone. Only 2 patients were unavailable for follow-up, leaving a final sample of 78 patients in the intervention group and 80 in the control group.
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Trial profile, indicating patient allocation and follow-up.
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Sociodemographic characteristics of the sample appear in Table 1. No significant differences between the intervention and control groups were observed. Table 1 shows that from 13% to 17% of the patients had a family history of prostate cancer. More than one third of patients indicated having had a previous PSA test, whereas about 1 patient in 5 was not sure about previous testing.
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Table 1. Sociodemographic Indicators*
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ANALYSIS
Change in Knowledge
Table 2 shows the average number (of 10) of prostate cancer knowledge questions answered correctly for all patients at the time of baseline assessment and at 2-week follow-up. On average, subjects in both groups answered slightly fewer than 3 of 10 questions correctly at baseline. At the 2-week follow-up, the intervention group answered an average of 4.8 questions correctly, an increase of about 2 questions (78% improvement; P=.001). Change in knowledge for the control group was not statistically significant. At the 2-week follow-up, 48 (62%) of 78 subjects in the intervention group answered at least 5 of the 10 questions correctly, compared with 25 (31%) of 80 controls (P=.001).
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Table 2. Scores on Prostate Cancer Knowledge Measure*
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For the intervention group, a statistically significant improvement in prostate cancer knowledge was observed for 7 of the 10 questions, compared with 1 question in the control group. Responses to the knowledge questions are given in Table 3. The intervention group showed improvements in knowledge about mortality due to early-stage prostate cancer, performance of PSA testing including predictive value, treatment complications, and the disadvantages of PSA testing. In contrast, no changes were observed in correct responses to the questions about the likelihood of cure for early-stage prostate cancer and advantages of PSA testing.
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Table 3. Responses to Specific Questions About Prostate Cancer and PSA Testing*
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Preferences for PSA Testing
Table 4 shows the percentage of patients indicating a preference for having the PSA test at the baseline assessment (preintervention) and at the 2-week follow-up. The percentage of subjects wanting the PSA test in the intervention group decreased by 17% (P=.01), whereas no significant change was observed for the control group. The absolute difference in preference for PSA testing at 2-week follow-up between the intervention subjects and controls was 18.5% (95% confidence interval [CI], 4.6%-32.4%; P=.009). This absolute reduction in screening preference of 18.5% means that for every 6 patients who viewed the videotape, 1 fewer patient would prefer to have the PSA test. Family history of prostate cancer was not related to PSA testing preferences at the 2-week follow-up for patients in either group.
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Table 4. Patients Preferring to Have the PSA Test*
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Among subjects indicating they had a previous PSA test at the baseline assessment, 22 (76%) of 29 from the intervention group and 33 (92%) of 36 from the control group indicated a preference for having the PSA test at the 2-week follow-up (21=3.08; P=.08). Among subjects indicating no previous PSA test at the baseline assessment, 26 (53%) of 49 from the intervention group and 31 (70%) of 44 from the control group indicated a preference for having the PSA test at the 2-week follow-up (21=2.96; P=.09).
Ratings of the Videotape
Table 5 presents subjects' ratings of the PSA videotape. Almost 80% of the subjects believed the amount of information was appropriate, the length of the tape was about right, and the presentation was balanced. Almost 90% of the subjects reported that the issues were presented clearly. Most subjects indicated that the videotape influenced their decision to have the PSA test, and they would recommend the videotape to other patients.
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Table 5. Patient Ratings of PSA Screening Videotape*
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Patient Utility Assessment and Preferences for PSA Testing
Subjects in the intervention plus utility assessment group were divided into those indicating a preference for having the PSA test in the future (n=22) and those unsure or preferring not to have the test (n=14). We expected that patients preferring PSA testing would associate greater utility (higher values) with complications of treatment for prostate cancer than those patients unsure or not wanting the test. Partial support for these differences was observed. Five of the 8 comparisons were in the expected direction, though none reached statistical significance. Only the utilities for urinary incontinence and erectile dysfunction from the time trade-off assessments were not in the expected direction.
COMMENT
Several observations can be made from our findings. First, the core knowledge of male primary care patients regarding epidemiology of prostate cancer, screening accuracy, treatment effectiveness, and complications is generally lacking. Second, a brief educational videotape can improve significantly patients' core knowledge about the risks and benefits of PSA testing. Third, such a videotape intervention appears to change patient preferences, leading to a decrease in the proportion of men wanting PSA testing. This change in preferences for PSA testing does not appear to be related to a family history of prostate cancer. Fourth, patients evaluated the videotape experience favorably and would recommend it to other patients. Finally, preferences for PSA testing are fairly consistent with patients' utilities for complications of treatment.
To our knowledge, our study is the first randomized controlled trial of a videotape-assisted, patient-educational approach to decision making for prostate cancer screening. Our findings support several previous trials of patient-educational interventions for prostate cancer screening. Members of the Prostate Patient Outcomes Research Team reported 2 studies of patient preferences for prostate cancer screening following patient-educational videotapes.10 Men attending a free PSA-screening clinic were assigned to the Shared Decision-Making programs videotape or to a videotape presentation emphasizing the importance of early detection of prostate cancer without mention of the controversy surrounding screening. A second group of men presenting for routine care at a general medicine clinic were assigned to the Shared Decision-Making programs videotape or to a no-videotape comparison group. (Neither study used random assignment of subjects because of logistical concerns.) Men in the second study who viewed the PSA videotape were about 50% less likely to have the test at their next opportunity and indicated their chances of having the test in the future were lower compared with men in the no-video group. This study further found that men viewing the PSA videotape were more likely to prefer watchful waiting as a treatment option (vs radical prostatectomy and radiation therapy) than were men in the comparison groups.
In a comparative trial, the impact of an informed-consent approach to PSA testing was considered.22 Primary care patients were randomized to an intervention script on PSA risks and benefits read by a research assistant or to a comparison group (although labeled a control group, this group received a brief statement about the availability of PSA testing for detecting early prostate cancer). A significant decrease in patient interest in PSA testing (measured by a 5-point Likert scale) was observed after the intervention.
In response to an increase in PSA testing for prostate cancer observed in May 1991, Group Health Cooperative of Puget Sound implemented a guideline that recommended against routine use of PSA screening for prostate cancer.23 The approach was described as fully informed decision making. Providers and patients were given educational materials on PSA testing with the goal of facilitating decision making based on patients' values. Providers were also given feedback on their PSA test ordering and literature updates on treatment for prostate cancer on a quarterly basis. They reported a drop in the rate of PSA test ordering of about 50% after implementation of the guideline. Outcome information on improvements in patient knowledge of prostate cancer screening and of treatment risks and benefits was not addressed.
Although we observed a decrease in patient preferences for PSA testing after the educational intervention, this should not be the primary goal of shared decision making. Rather, demonstrating that patients understand the risks and benefits of screening and that the information is provided in a clear and balanced fashion is consistent with the objectives of shared decision making. Increases in screening as a result of patient education or no change in screening behavior, assuming improvements in knowledge occur also, are equally acceptable outcomes.
Flood et al10 make the point that, although involving patients in treatment decisions is increasingly recognized as important, patient involvement in screening decisions is far less common and less accepted. Abnormal or indeterminate screening results can lead to a cascade of events, many of which may be particularly unpleasant for patients. In situations where there is uncertainty about choosing an optimal treatment strategy, including watchful waiting, the decision to screen should involve the preferences of a well-informed patient.
That few patients were able to correctly answer the question on the proportion of men with abnormal PSA test results who would have prostate cancer is interesting. After viewing the videotape, only 35% of the patients answered this question correctly. This question is one of predictive value of screening tests. Educating patients about probability revision may prove a difficult task.
A strength of our study is that we developed a new measure of prostate cancer knowledge, based on careful review of the literature and material presented in the PSA videotape and brochure. Attention was given to reading level, clarity of presentation (with an option for patients not willing to offer a guess), brevity, and breadth of content. The measure was translated into Spanish and backtranslated into English to check accuracy.
Our study is limited by the use of a single clinical site. The relationship between patients' stated preferences for PSA testing and subsequent screening behavior also is unclear. A longer follow-up would be needed to assess the relationship. This study is akin to an efficacy trial (ie, randomized and placebo controlled, with high adherence to the study protocol). It does not address pragmatic issues of incorporating such approaches into busy clinical settings, the process of decision making, or how the patient and provider interact toward determining a strategy. Furthermore, decision making for prostate cancer screening (and most clinical decision making) does not occur outside of the patient's social context.9 We need to understand better how information is conveyed to patients, whether preferences of providers relate to how information is presented, and how other members of the patient's social network are involved in this process. Many patients may defer to physicians, relying on their expertise to select the best option, whereas other patients expect to be highly involved in determining their care.24 Although the PSA videotape appears to lead to increased knowledge, it does not necessarily clarify patients' values.
Wennberg15(p16) has argued that "[m]edicine's fifth revolution is the democratization of the doctor-patient relationship—the empowerment of providers to communicate and the empowerment of patients to choose among the options available to them...." The shared decision-making approach is a considerable advancement in informed consent, as the patient becomes an active participant in the decision-making process.16 Patient-educational approaches to decision making about PSA testing should be adopted on a broad scale. The effectiveness of such interventions in community settings with heterogeneous patient populations is an important next step in evaluating shared decision-making approaches.
AUTHOR INFORMATION
Accepted for publication August 10, 1998.
This project was supported by grants from the American Academy of Family Physicians Foundation and the American Academy of Family Physicians, Kansas City, Mo, and grant D32-PE10158-01 from the Bureau of Health Professions, Health Resources and Services Administration, Rockville, Md.
We acknowledge the assistance of Kristi O'Dell, PhD, Carol Carlson, Joal Hill, JD, MPH, Anna Catalina Triana, MD, and Kristy Smith in collecting the data, and Lynn M. Alperin for her editorial expertise.
Reprints: Robert J. Volk, PhD, Department of Family and Community Medicine, Baylor College of Medicine, 6560 Fannin, Suite 1406, Houston, TX 77030 (e-mail: bvolk{at}bcm.tmc.edu).
From the Department of Family and Community Medicine, Baylor College of Medicine, Houston, Tex (Drs Volk and Spann), and the Department of Family Medicine, The University of Texas Medical Branch at Galveston (Dr Cass).
REFERENCES
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1. American Cancer Society. Prostate Cancer ACS Checkup Guidelines. Available at: http://www.cancer.org. Accessed December 2, 1997.
2. US Preventive Services Task Force. Guide to Clinical Preventive Services. 2nd ed. Baltimore, Md: Williams & Wilkins; 1996.
3. Coley CM, Barry MJ, Fleming C, Mulley AG. Early detection of prostate cancer, I: prior probability and effectiveness of tests. Ann Intern Med. 1997;126:394-406.
FREE FULL TEXT
4. Coley CM, Barry MJ, Fleming C, Fahs MC, Mulley AG. Early detection of prostate cancer, II: estimating the risks, benefits and costs. Ann Intern Med. 1997;126:468-479.
FREE FULL TEXT
5. American College of Physicians. Clinical guideline, III: screening for prostate cancer. Ann Intern Med. 1997;126:480-484.
FREE FULL TEXT
6. Spann SJ. Prostate cancer screening: what's a physician to do [editorial]? Am Fam Physician. 1997;56:1563-1568.
ISI
| PUBMED
7. Kassirer JP. Incorporating patients' preferences into medical decisions. N Engl J Med. 1994;330:1895-1896.
FREE FULL TEXT
8. Cantor SB, Spann SJ, Volk RJ, Cardenas MP, Warren MM. Prostate cancer screening: a decision analysis. J Fam Pract. 1995;41:33-41.
ISI
| PUBMED
9. Volk RJ, Cantor SB, Spann SJ, Cass AR, Cardenas MP, Warren MM. Preferences of husbands and wives for prostate cancer screening. Arch Fam Med. 1997;6:72-76.
FREE FULL TEXT
10. Flood AB, Wennberg JE, Nease RF, Fowler FJ, Ding J, Hynes LM. The importance of patient preference in the decision to screen for prostate cancer. J Gen Intern Med. 1996;11:342-349.
ISI
| PUBMED
11. Barry MJ, Fowler FJ, Mulley AG, Henderson JV, Wennberg JE. Patient reactions to a program designed to facilitate patient participation in treatment decisions for benign prostatic hyperplasia. Med Care. 1995;33:771-782.
FULL TEXT
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ISI
| PUBMED
12. Liao L, Jollis JG, DeLong ER, Peterson ED, Morris KG, Mark DB. Impact of an interactive video on decision making of patients with ischemic heart disease. J Gen Intern Med. 1996;11:373-376.
ISI
| PUBMED
13. Kasper J, Mulley A, Wennberg J. Developing shared decision-making programs to improve the quality of health care. Qual Rev Bull. 1992;18:183-190.
14. Randall T. Producers of videodisc programs strive to expand patient's role in medical decision-making process. JAMA. 1993;270:160-162.
FREE FULL TEXT
15. Wennberg J. Shared decision making and the future of managed care. Dis Manage Clin Outcomes. 1997;1:15-16.
16. Deber RB. Shared decision making in the real world. J Gen Intern Med. 1996;11:377-378.
ISI
| PUBMED
17. Sox HC Jr, Blatt MA, Higgins MC, Marton KI. Medical Decision Making. Newton, Mass: Butterworth-Heinemann; 1988.
18. Siegel S, Castellan NJ Jr. Nonparametric Statistics for the Behavioral Sciences. New York, NY: McGraw-Hill Book Co; 1988.
19. Hintze JL. PASS 6.0 User's Guide. Kaysville, Utah: Number Cruncher Statistical Systems; 1996.
20. Sackett DL. On some clinically useful measures of the effects of treatment. Evidence-Based Med. 1996;1:37-38.
21. Norusis MJ. SPSS for Windows [computer program]. 6.0 ed. Chicago, Ill: SPSS Inc; 1993.
22. Wolf AMD, Nasser JF, Wolf AM, Schorling JB. The impact of informed consent on patient interest in prostate-specific antigen screening. Arch Intern Med. 1996;156:1333-1336.
FREE FULL TEXT
23. Handley MR. The use of prostate specific antigen for prostate cancer screening: a managed care perspective. J Urol. 1994;152:1689-1692.
ISI
| PUBMED
24. Deber RB, Kraetschmer N, Irvine J. What role do patients wish to play in treatment decision making? Arch Intern Med. 1996;156:1414-1420.
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| FULL TEXT
Screening for prostate cancer in the UK
Donovan et al.
BMJ 2001;323:763-764.
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Use of Videotaped Interventions in Research
Steinke
West J Nurs Res 2001;23:627-643.
ABSTRACT
Information Disclosure and Beyond:: How Do Patients Understand and Use the Information They Report They Want?
Mazur
Med Decis Making 2000;20:132-134.
Involving Patients in Medical Decisions: How Can Physicians Do Better?
Barry
JAMA 1999;282:2356-2357.
FULL TEXT
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