Complete Diagnostic Evaluation in Colorectal Cancer Screening: Research Design and Baseline Findings

Preventive Medicine 33, 249–260 (2001) doi:10.1006/pmed.2001.0878, available online at http://www.idealibrary.com on

Complete Diagnostic Evaluation in Colorectal Cancer Screening: Research Design and Baseline Findings1 Ronald E. Myers, Ph.D.,*,2 Barbara Turner, M.D., M.Ed.,† David Weinberg, M.D.,‡ Walter W. Hauck, Ph.D.,§ Terry Hyslop, Ph.D.,§ Timothy Brigham, Ph.D.,¶ Todd Rothermel,㥋 James Grana, Ph.D.,㥋 and Neil Schlackman, M.D.㥋 *Division of Medical Oncology and Medical Genetics, ‡Division of Gastroenterology, and §Biostatistics Section, Division of Clinical Pharmacology, Department of Medicine, and ¶Office of Continuing Medical Education, Thomas Jefferson University, Philadelphia, Pennsylvania 19107; †General Internal Medicine, University of Pennsylvania, 1119 Blockley Hall, 423 Guardian Drive, Philadelphia, Pennsylvania 19104; and 㥋Aetna U.S. Healthcare, 980 Jolly Road, Blue Bell, Pennsylvania 19422 Published online August 17, 2001

Background. While indicated by guidelines, complete diagnostic evaluation, or CDE (i.e., colonoscopy or combined flexible sigmoidoscopy plus barium enema X ray), is often not recommended and performed for persons with an abnormal screening fecal occult blood test (FOBT) result. We initiated a randomized trial to assess the impact of a physician-oriented intervention on CDE rates in primary care practices. Methods. In 1998, we identified 1,184 primary care physicians (PCPs) in 584 practices whose patients received FOBTs that are mailed annually by a managed care organization screening program. A total of 470 PCPs in 318 practices completed a baseline survey. Practices were randomly assigned either to a Control Group (N ⴝ 198) or to an Intervention Group (N ⴝ 120). Control Group practices received the screening program. Intervention Group practices received the screening program and the intervention (i.e., CDE reminder–feedback plus educational outreach). Practice CDE recommendation and performance rates are the primary outcomes to be measured in the study. Results. Baseline CDE recommendation and performance rates were low and were comparable in Control and Intervention Group practices (54 to 57% and 39 to 40%, respectively). PCPs in the practices tended to view FOBT screening and CDE favorably, but had concerns about screening efficacy, time involved in CDE, and

1 The National Cancer Institute (Grant 5R01 CA68683) provided funding for this study. 2 To whom reprint requests should be addressed at the Division of Medical Oncology and Medical Genetics, Department of Medicine, Thomas Jefferson University, 1100 Walnut Street, Suite 400, Philadelphia, PA 19107. Fax: (215) 503-9506.

patient discomfort and adherence. Control Group physicians were more likely than Intervention Group physicians to believe that a mail-out FOBT screening program helps in the practice of medicine. Conclusions. We were able to enroll a high proportion of targeted primary care practices, measure practice characteristics and CDE rates at baseline, and develop and implement the intervention. Study outcome analyses will take into account baseline differences in practice characteristics. 䉷 2001 American Health Foundation and Academic Press

Key Words: colorectal neoplasms, diagnosis; colorectal neoplasms, prevention and control; mass screening; physician’s role. INTRODUCTION

In 2001, there will be approximately 135,400 new cases of and 56,700 deaths from colorectal cancer [1]. To reduce colorectal cancer morbidity and mortality among men and women 50 or more years of age, the United States Preventive Services Task Force, the American Cancer Society, the World Heath Organization, and other organizations recommend annual screening with fecal occult blood tests (FOBTs). Alternative colorectal cancer screening tests that are recommended include periodic flexible sigmoidoscopy, barium enema X ray, and colonoscopy [1, 2]. The most commonly used screening modality, however, is the FOBT. Findings from controlled FOBT screening trials in the United States and Europe have shown significant reductions in colorectal cancer incidence and mortality and have documented a beneficial shift to earlier stage cancers and a higher rate of adenomatous polyp detection among screenees compared with controls [3–9]. In

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0091-7435/01 $35.00 Copyright 䉷 2001 by American Health Foundation and Academic Press All rights of reproduction in any form reserved.

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the trials, patients with FOBT⫹ results were routinely followed up with complete diagnostic evaluation, or CDE (i.e., either colonoscopy or combined flexible sigmoidoscopy and barium enema X ray). CDE allows for thorough inspection of the large bowel and, thus, facilitates the detection of colorectal neoplastic lesions. Reductions in colorectal cancer mortality observed in the trials are likely to have resulted from the detection and treatment of asymptomatic, early stage colorectal cancers and adenomas [10]. It is reasonable to assume that the potential benefits of FOBT screening will not be realized if large numbers of FOBT⫹ patients do not undergo CDE [11]. Outside of randomized trials, however, patients who have screening FOBT⫹ results often do not undergo CDE [12, 13]. This situation, which has been highlighted recently in a report that evaluated diagnostic testing among Medicare beneficiaries following an initial FOBT [14], has been attributed largely to primary care physician reluctance to recommend and perform CDE for screening FOBT⫹ patients [13]. In 1997, we obtained support from the National Cancer Institute and Aetna U.S. Healthcare for a research project on CDE in FOBT⫹ patients. The project, referred to here as “The CDE Study,” was a randomized trial designed to evaluate the impact of a physician intervention (i.e., CDE reminder–feedback and educational outreach) on CDE recommendation and performance rates in primary care practices. In this paper, we describe the study design and present baseline findings. RATIONALE FOR THE PHYSICIAN INTERVENTION

MacDonald et al. [15] demonstrated that the use of physician reminders produced a dramatic increase in the provision of preventive care, including cancer detection, to patients seen in a general medicine clinic. The addition of reminders to existing physician office operational procedures has been explored in several studies [16–19]. In a meta-analysis of studies of physician reminders on cervical cancer screening and tetanus immunizations, Austin, Balas, Mitchell, and Ewigman [20] reported that physician reminders significantly increased performance of these preventive health behaviors. In terms of colorectal cancer screening, Litzelman, Dittus, Miller, and Tierney [21] found that requiring physicians to record actions they took in response to reminder prompts improved patient completion of FOBT screening by 20%. Results of these and other investigations indicate that physician reminders, especially those that require a physician response, can significantly increase physician-directed cancer-preventive behaviors. Providing physician performance feedback also appears to have a salutary effect on physician behavior in relation to a variety of cancer prevention and control activities [22–24]. Curtis et al. [25] have shown that

the use of physician performance feedback can increase cervical cancer screening in primary care practices. Winickoff et al. [26] also showed that physician performance feedback can stimulate increased patient colorectal cancer screening. More recently, Dietrich, Sox, Tosteson, and Woodruff [27] have also reported that this type of approach can improve the performance of breast and colorectal cancer screening in primary care practices. According to Greco and Eisenberg [28], studies that have indicated positive impact from performance feedback are those in which feedback was provided in a timely fashion and practitioners recognized the need for improvement. Tierney, Hui, and MacDonald [29] demonstrated the importance of performance feedback timing. They found that when an immediate reminder and performance feedback were used in a general medical practice, FOBT screening increased by more than 50%. In a recent article, Thomson-O’Brien et al. [30] reviewed 37 studies that investigated the impact of medical chart audit plus feedback on physician behavior. A number of physician behaviors, including diagnostic test ordering, prescribing practices, preventive care, and general management of health problems, were targeted in the studies reviewed. They concluded that the use of reminder–feedback is likely to have an impact on particular types of physician behaviors, such as medication prescribing and diagnostic test ordering. Cohen, Halvorson, and Gosselink [31] have argued that educational outreach may be an effective way to influence physicians to prescribe preventive behaviors to their patients. In their review, Davis et al. [32] found improvement in physician performance in most studies in which continuing medical education (CME) strategies (e.g., educational outreach visits, opinion leaders, patient-mediated interventions, and multifaceted activities) were used. The academic detailing office visit is of particular interest in our study. Academic detailing is a face-to-face educational session that allows for the distribution of educational information, identification of barriers to desired outcomes, and encouragement of sustained practice pattern change [24]. Soumerai [33] reviewed four randomized trials of academic detailing as a method of changing primary care physician performance related to the management of psychiatric disorders. In each trial, outcomes of interest were changes in the prescribing of psychoactive medications. The author observed that academic detailing methods were effective in changing physician behavior. The most effective approaches were those that were sponsored by credible organizations, addressed salient motivational barriers to change, emphasized a few key messages that address identified barriers, employed illustrated educational materials to communicate these messages, used personal two-way communication to engage physicians in

COMPLETE DIAGNOSTIC EVALUATION IN COLORECTAL CANCER SCREENING

attending to their behavioral patterns and related consequences, and involved brief face-to-face visits by trained educational specialists to encourage and reinforce behavior change. Thomson-O’Brien et al. [34] recently reviewed 18 clinical trials of educational outreach as a strategy to change physician behaviors related to smoking cessation counseling and disease management (i.e., asthma, diabetes, otitis media, hypertension, anxiety, and acute bronchitis). They reported that all of the educational outreach visit interventions consisted of combined methods, including academic detailing visits, reminders, and chart audit plus feedback. Overall, they found that combined interventions had a significant impact on physician behavior. While it is assumed that such effects reflect intervention impact relative to physician knowledge and awareness, the underlying mechanism(s) of behavior change was not well documented. For this study, we developed a combined reminder– feedback and educational outreach intervention in accordance with the Diagnostic Evaluation Model or DEM. This model, which is based on Social Cognitive Theory [35] and the Theory of Reasoned Action [36], defines conceptual dimensions related to physician behavior. As shown in Fig. 1, the model includes the following factors: physician practice environment and characteristics, practitioner background and experience, physician cognitive and psychological representations, physician social support and influence, patient characteristics, and physician intention. Elsewhere, it has been suggested that these factors may be useful in predicting physician behavior related to colorectal cancer screening [37] and CDE recommendation and

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performance [38]. We hypothesized that a combined CDE reminder–feedback and educational outreach intervention would affect practice-level CDE recommendation and performance (i.e., primary outcomes) by influencing physician cognitive representations related to colorectal cancer screening and CDE, psychosocial representations of colorectal cancer screening and CDE, and intention to recommend and perform CDE for FOBT⫹ patients (i.e., secondary outcomes). These hypotheses will be tested at the conclusion of data collection. METHODS

Study Design In The CDE Study, managed care organization (MCO)-affiliated primary care practices in which one or more primary care physicians (PCPs) completed a Baseline Survey were randomly assigned either to a Control Group or to an Intervention Group. All practices were exposed to an existing colorectal cancerscreening program that the MCO makes available directly to its members. In this program, an FOBT kit is mailed annually to patients who are 50 or more years of age. Intervention Group practices received a physician intervention in addition to the screening program. The study was designed to provide at least 90% power to detect a 20 percentage-point difference in CDE performance and recommendation rates between the Control Group and the Intervention Group, using a ␹ 2 test and a significance level of 0.05. The size of the intervention effect was considered to be clinically meaningful. We elected to use a randomization plan that required

FIG. 1. Diagnostic Evaluation Model. Information on patient characteristics and behavior-related outcomes are not available for inclusion in this report.

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fewer Intervention Group practices than Control Group practices. This decision was made to increase the efficiency of staff and resource utilization related to delivering the intervention. Power calculations for a 2:3 randomization scheme indicated that at the end of the trial, CDE rate analyses would require at least 108 Intervention Group and 162 Control Group practices. To allow for the potential loss of up to 10% of randomized practices over the course of 2 years, we determined that a total of 318 practices, each with at least one surveyed PCP, would be sufficient for the study. The estimate for practice attrition was based on the fact that the observation was relatively short and on the opinion of MCO personnel that practice affiliation was likely to be stable during the period. CDE rates will be computed at the end of the study and will use the patient as the unit of analysis. However, patient results within a practice may be correlated. To address this issue, we were conservative in our power calculations. As we did not know how much intrapractice correlation to allow for, we used a value of 1.0. Thus, we effectively powered the study as if we had one subject per practice. Physician and Practice Recruitment and Random Assignment to Study Groups In late 1997, we established eligibility criteria that could be used to identify MCO primary care practices for inclusion in The CDE Study. We decided to include those practices located in southeastern Pennsylvania and in New Jersey that had had three or more patients who had a screening FOBT⫹ result during an 18-month period beginning January 1, 1994, in an established colorectal cancer screening program called the US Healthcare Check Program. Practices in this area were selected in order to facilitate office visits by project nurse educators headquartered in Philadelphia. The number of patients previously seen (ⱖ3) was set to allow for the computation of rates and to increase the likelihood that an adequate number of FOBT⫹ patients would be identified during the study observation period. Further, the 18-month baseline time frame was selected to minimize the effect of short-term fluctuations in FOBT returns on baseline CDE rates and, thus, provide more accurate measures. The US Healthcare Check Program was started in 1986. In the program, a central screening office mails an FOBT kit annually to MCO subscribers who are 50 or more years of age. The FOBT kit includes an introductory letter, information about colorectal cancer, three Hemoccult II FOBT slides with instructions, and a postage-paid return envelope. Printed instructions regarding diet and medication restrictions during the test period are also provided. Individuals who have not returned a completed FOBT within 60 days receive a

mailed reminder. FOBT cards are returned directly to Thomas Jefferson University Hospital Clinical Laboratories for analysis. This laboratory notifies the screenee’s primary care practice of test results and also sends a notice to the screenee. As shown in Fig. 2, we identified 584 practices that fulfilled study eligibility criteria (i.e., had ⱖ3 FOBT⫹ patients in the baseline period, January 1, 1994, to June 30, 1995, and were located in southeastern Pennsylvania and southern New Jersey). There were 1,184 PCPs in these practices. Following a protocol approved by the Thomas Jefferson University Institutional Review Board, project staff sent each of the PCPs a letter describing The CDE Study. The letter explained that we planned a randomized trial that would allow us to test the impact of the physician intervention on the follow-up of screening FOBT⫹ patients. It also explained that PCPs who enrolled in the study would be awarded CME credits based on their participation in different study activities (e.g., reporting on patient follow-up, completing survey questionnaires, or participating in educational outreach). A study enrollment form accompanied the letter. Nonrespondents were sent a reminder and another copy of the letter and enrollment form after 30 days. There were 838 PCPs from 431 practices who responded indicating that they would be willing to participate in the study. The 18 practices with 62 PCPs who participated in pilot study or focus group activities were eliminated from further participation in the study. We mailed a self-administered version of the Baseline Survey instrument to 776 PCPs in the remaining 413 practices. A total of 357 PCPs completed the mailed survey and returned it to the project office. In summer 1998, Mathematica Policy Research, Inc., a professional survey company in Princeton, New Jersey, contacted physicians who did not return the mailed questionnaire in order to administer a telephone version of the survey. This effort produced 113 more completed survey questionnaires. Thus, a total of 470 PCPs in 318 practices completed a Baseline Survey. There were an additional 168 PCPs in these practices who did not complete a survey. There remained 95 practices with 138 PCPs from which no completed Baseline Surveys were received. Reasons that PCPs did not complete a Baseline Survey included refused (15%), left practice (8%), deceased (1%), and field period ended before telephone survey was administered (76%). It should be noted that budgetary considerations dictated a field period of approximately 1 month. As shown in Fig. 2, practices with one or more PCPs who completed a Baseline Survey were randomly assigned either to a Control Group (N ⫽ 198) or to an Intervention Group (N ⫽ 120). Control Group practices included 278 surveyed and 102 unsurveyed PCPs, while

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FIG. 2. Flow of practices and physicians into The CDE Study.

Intervention Group practices included 192 surveyed and 66 unsurveyed PCPs. Intervention Components The physician-oriented intervention included two components: CDE reminder–feedback and educational outreach. CDE Reminder–Feedback Members of the research team developed the reminder–feedback component of the intervention. The reminder was a mailed patient-specific internal chart audit (ICA) form (i.e., the reminder) sent to each primary care practice 60 days after a patient’s FOBT⫹ result date. The ICA form included patient name, insurer identification number, and FOBT⫹ result date. PCPs in these practices were asked to indicate whether CDE was recommended and performed and, when applicable, provided the exam date(s) and diagnosis reached. If CDE had not been performed, the PCP provided a reason. Completed forms were sent to The CDE Study project office for data entry. PCPs who did not

return a completed form within 30 days received a second mailed form. The other feature of this intervention component was a mailed CDE feedback report. This report, which was sent to practice PCPs on a semiannual basis, identified patients who had had a screening FOBT⫹ result during the prior 6 months. It also provided the patient’s FOBT⫹ result date and CDE status as reported on the ICA form and in MCO administrative data. This intervention component was designed to make physicians aware of patients who were eligible for CDE. Educational Outreach Members of the research team developed the educational outreach component of the intervention. This component included: (a) two in-office academic detailing visits and (b) a tailored letter and telephone call. At the first academic detailing visit, a nurse educator narrated a color slide presentation on colorectal cancer screening and CDE and led a discussion on barriers to CDE. The presentation provided national data on

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colorectal cancer incidence, mortality, and stage-specific survival, as well as results for FOBT screening randomized trials. After this presentation, the nurse educator provided each PCP a copy of an initial educational brochure. This report reviewed practice-specific CDE rates and summarized barriers to CDE that were reported by PCPs in the practice on ICA forms. An example of a CDE barrier is physician belief that performing a repeat FOBT is appropriate follow-up for patients with an initial FOBT⫹ result. Another barrier is the perception that patients are unlikely to adhere to CDE when recommended. Questions about the report were addressed and barriers cited by physicians in the practice were discussed. A packet of print materials was also provided for each PCP in the practice, including those who did not attend this session. This packet included a copy of key slides and a visit evaluation form, with a postage-paid return envelope. At the second visit, which was scheduled to take place in 6 months, contents of the original slide presentation were reviewed briefly. A second educational brochure, which summarized practice-specific CDE rates and aggregated data from the ICA forms on diagnostic outcomes and reasons CDE was not performed, was distributed and discussed. Two half-time project nurse specialists responsible for academic detailing received training in the areas of colorectal cancer screening and CDE and manner of presentation. Training included review of a training manual developed for the study and selected articles from the literature, discussion of manual content with study co-investigators, role play of the academic intervention delivery before study co-investigators, and coinvestigator critique of videotaped mock visits with volunteer primary care physicians. In addition, supervisory staff accompanied the nurse specialists during selected office visits. At the conclusion of each office visit, PCPs in attendance were also asked to complete an evaluation form related to the presentation. The tailored PCP letter feature of educational outreach took the form of a letter sent to each PCP and follow-up telephone call. The letter identified PCP-specific barriers to recommending CDE. These barriers were defined in terms of variables that were negatively correlated with physician intention to recommend CDE as measured on the Baseline Survey (i.e., uncertainty about recommending CDE, belief that CDE-related costs may affect utilization, concern about CDE-related patient discomfort and nonadherence, and belief that CDE is not standard practice). Low intention to recommend CDE, itself, was also considered to be a barrier to CDE. Following delivery of the letter, a study coinvestigator called the recipient. During the call, the study co-investigator and PCP reviewed the contents of the letter, sought to understand why the listed barriers

existed, and addressed outstanding PCP concerns regarding CDE. The academic detailing visits and tailored letter and call were intended to provide information that would serve to increase physician knowledge about colorectal cancer screening and CDE, favorable perceptions about screening and CDE, and intention to recommend CDE to FOBT⫹ patients. Educational outreach materials and procedures were reviewed in a PCP focus group conducted prior to the delivery of the intervention. Measuring Baseline CDE Recommendation and Performance Rates In order to compute baseline CDE rates, we identified patients who had had an FOBT⫹ result from January 1994 to June 1995 in participating practices. If there were more than nine FOBT⫹ patients identified in a given practice during the target period, a random sample of nine patients in the practice was selected for data collection. We requested follow-up information for the patients by sending ICA forms to each practice. For each FOBT⫹ patient, the ICA form asked for information on procedures that were recommended and performed within 120 days after the patient’s FOBT⫹ result date. This time frame was viewed as adequate for the procedures to have been recommended and performed. For each FOBT⫹ patient, the physician was asked to indicate whether a flexible sigmoidoscopy, barium enema, or colonoscopy had been advised, advised but not performed, or performed. If a procedure had been performed, the procedure date was requested. Space was provided on the form to allow the physician to explain why the procedures were not performed. Completed forms were returned to the study central office. Decision rules were developed to decide on patient eligibility for CDE. Reasons that a patient would be ineligible for CDE include patient unknown to the practice, patient had CDE performed within 3 years prior to the FOBT⫹ result, patient left the practice before CDE could be recommended, or patient was deceased before CDE could be recommended. Patients determined to be ineligible for CDE were excluded from CDE rate computations. For those who were eligible for CDE, the research team also reviewed MCO administrative claims data (administrative data review or ADR) on colonoscopy performance. By combining ICA and ADR data, we determined CDE recommendation and performance status for each eligible patient. In a pilot study of different methods for measuring CDE [39], we have reported that this method for measuring CDE recommendation and performance is highly sensitive and specific (ⱖ0.90) compared with the “gold standard” for assessing CDE rates (i.e., external chart audit and ADR).

COMPLETE DIAGNOSTIC EVALUATION IN COLORECTAL CANCER SCREENING

Variables Measured on the Baseline Survey Physician responses to items included on the Baseline Survey were defined in terms of single items and scales. Single-item practice environment measures on the Baseline Survey included practice administrative arrangement (i.e., practice with one physician (solo) versus more than one physician (group)), participation in an integrated health care delivery system, and practice geographic location. In terms of physician background and experience, respondents provided information on the following singleitem variables: age, gender, race/ethnicity, years practicing medicine, medical specialty, board certification status, and recent experience with colorectal cancer and polyp patients and early detection. Relative to patient encounters, we used single items to measure the following: number of newly diagnosed colorectal cancer patients seen in the previous 12 months, percentage of newly diagnosed patients identified by FOBT screening, number of newly diagnosed colorectal polyp patients seen in the previous 12 months, and percentage of newly diagnosed colorectal polyp patients identified by FOBT screening. Details concerning the rationale used to identify cut-points for these items and those included as measures of physician cognitive and psychological representations, physician social support, and influence are presented elsewhere [39]. Physician cognitive and psychological representations related to FOBT screening and CDE were measured as single items and scales. Initially, a principal components factor analysis with varimax rotation was completed using responses to survey items related to physician perceptions of FOBT screening and CDE. Exploratory factor analysis was performed because many of the items had not been used in research previously done by the research team [39]. This analysis led to the identification of five scales. These scales included in the following scales uncertainty about recommending CDE (4 items, ␣ ⫽ 0.87), belief that CDErelated costs may affect utilization (2 items, ␣ ⫽ 0.79), concern about patient CDE-related discomfort and nonadherence (2 items, ␣ ⫽ 0.84), belief in the benefit of FOBT screening (2 items, ␣ ⫽ 0.86), and belief that CDE requires a lot of physician and patient time (2 items, ␣ ⫽ 0.87). As long as at least half of the items that made up a scale had a response, the scale score was determined by the average of item responses. This approach is consistent with that recommended by Fayers, Curran, and Machin [40] for the treatment of missing data. The scale score for a practice was the average of the responses of PCPs in that practice. Cognitive and psychological survey items that did not form reliable scales were treated as individual independent variables. These items include the belief that a mailed

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FOBT screening program helps in the practice of medicine, the belief that CDE will detect colorectal cancer in FOBT⫹ patients, and the belief that CDE will detect colorectal polyps in FOBT⫹ patients. Physician social support and influence was measured in terms of how PCPs perceived CDE in relation to standard practice. The following single item was assessed: belief that CDE is standard practice in the community. In terms of patient characteristics, we assessed FOBT⫹ patient age, gender, medical history, and risk factors in study group practices by using information in the MCO administrative database. Data on patient race/ethnicity are not available from this source. Finally, we completed a confirmatory factor analysis on 10 items related to physician intention to recommend CDE. Confirmatory factor analysis was used to assess a set of items that had been used by the research team in earlier research [39]. Each of the items presented a clinical scenario that may be encountered with FOBT⫹ patients. Intention scale scores were imputed when at least half of the items that make up the factor had response information. Scores were then standardized to the number of items in the scale and an average score was computed for each practice. Scale score cutpoints were set in order to differentiate practices according to low, moderate, and high CDE intention. It was expected that this categorizing scheme, ultimately, would be helpful in identifying practices that could benefit most from exposure to the intervention. The CDE intention scale was found to be highly reliable (␣ ⫽ 0.92). Specific items included in the scale are included in the Appendix. Data Analysis Baseline CDE rates were computed from ICAs for 2,349 FOBT⫹ patients. An ICA form was returned for 2,240 (95%) of these patients. If no ICA form was returned for a patient, we assumed that CDE had not been recommended or performed. CDE rates were computed based on ICA data only. The study groups were compared using an unadjusted logistic regression model with GEE adjustment for clustering of patients within practices [41]. Practice-level measures of associated DEM variables were computed for the Control and Intervention Groups using Baseline Survey data. The research team also inspected administrative data on several DEM variables. These variables included practice environment (i.e., practice administrative arrangement and state in which the practice was located) and physician background and experience (i.e., PCP age, gender, years practicing medicine, and board certification status). Findings from univariate analyses using physician background and experience variables showed that measures from these two data sources were comparable. Since Baseline Survey data were available for all

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318 practices in the Control and Intervention Groups, we chose to use survey data to compute practice-level measures for the DEM variables for these two groups. Survey data only were used in comparisons involving Control and Intervention Groups. The ␹ 2 test was used in these comparisons. ICA and survey data were doubleentered and cleaned by experienced staff. RESULTS

Baseline CDE Recommendation and Performance Rates CDE rates were computed for the baseline period in each of the 413 participating primary care practices. The distribution of these patients across study groups was as follows: Observation Group (N ⫽ 639), Control Group (N ⫽ 1,051), and Intervention Group (N ⫽ 659). Overall, 1,328 (57%) patients were recommended to have CDE. The CDE recommendation rates across the Observation Group, Control Group, and Intervention Group practices were 57, 58, and 54%, respectively. In addition, CDE was performed for 932 (40%) FOBT⫹ patients. CDE performance rates for the three study groups were 39, 40, and 40%, respectively. The observed differences in CDE rates across study groups were not statistically significant. DEM Measures Data on DEM measures for practices in the Control and Intervention Groups are shown in Table 1. In relation to practice environment, almost half of the practices were solo practices and only one-third were affiliated with an integrated health care delivery system. Most of the practices were located in Pennsylvania. In terms of the distribution of physician background and experience measures, most practices were comprised of PCPs who were male, white, trained in Family Medicine, and board certified. In about half of the practices the PCPs had a median age of 45 or more years and had been in practice for a median of 18 or more years. Survey respondents in most of the practices indicated that they had seen 3 or more newly diagnosed colorectal cancer patients in the previous year. PCPs in half of the practices stated that they had seen 10 or more colorectal polyp patients in the previous year. Further, PCPs in most practices reported that FOBT screening led to the diagnosis in over half of their colorectal cancer and polyp patients. In relation to cognitive and psychological representations, the overwhelming majority of practices included PCPs who believed the MCO screening program helps in the practice of medicine, thought that FOBT screening benefits their patients, and had little uncertainty about recommending CDE. There was less consensus on the belief that CDE is likely to detect colorectal

cancer and polyps. In addition, PCPs in almost half of the practices expressed some concern about CDErelated patient discomfort and nonadherence, and practitioners in more than half of the practices were concerned about the time involved in CDE performance. The belief that CDE-related costs may affect utilization was held by about one-fifth of PCPs. Social support and influence relative to CDE was reported to be low. That is, PCPs in only a handful of practices believe that CDE is routinely recommended. PCPs in only about onefourth of practices reported a high intention to recommend CDE. When Control and Intervention Groups on DEM measures were compared, we determined that PCPs in the Control Group were more likely to believe that the MCO screening program helped them in the practice of medicine (P ⬍ 0.01). CONCLUSION

We found that baseline CDE recommendation and performance rates were low. These findings are consistent with the few reports that have appeared in the literature and provide additional evidence that performance of CDE in colorectal cancer screening should not be assumed. This information highlights the need for screening programs to routinely assess CDE recommendation and performance in order to ensure quality of care. It is also the case that little research has been reported on factors that help to explain why CDE rates are low. Research, such as the study described here, should provide insights into why this situation exists and what steps can be taken to increase appropriate CDE utilization. In relation to measuring CDE rates, we have used a method that involves physician self-report and administrative data. As noted earlier, this approach has been determined to be highly reliable for measuring both CDE recommendation and performance. It should be noted that we have found that more than 90% of the ICA forms sent to PCPs in the study were completed and returned to the research team. The application of this method beyond the scope of this study may be feasible in settings where detailed administrative data are routinely collected on the performance of procedures. Survey data collected in this study indicate that PCPs tend to view FOBT screening and CDE as worthwhile activities. Interestingly, some PCPs expressed concern about CDE-related costs to the practice, time and effort required of physician and patient, and patient discomfort and adherence. In addition, PCPs tended not to view the performance of CDE as standard practice in the community. For responses to some survey items (e.g., physician belief in the benefit of FOBT screening and follow-up, uncertainty about recommending CDE,

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TABLE 1 Attributes of Surveyed Practices by Study Group Study group Intervention (N ⫽ 120)

Practice environment Administrative arrangement Solo Group Geographic location Pennsylvania New Jersey Participation in an integrated health care delivery system No Yes Physician background and experience Median age ⱕ45.5 years ⬎45.5 years Gender All male All female or male and female Board certification status 100% board certified ⬍100% board certified Race/ethnicity All Caucasian Other Median years in medical practice ⱕ18.5 years ⬎18.5 years Number of newly diagnosed CRC patients seen in prior year ⱕ3 patients ⬎3 patients Percentage of CRC patients diagnosed by FOBT screening ⱕ50% ⬎50% Number of newly diagnosed polyp patients seen in prior year ⱕ10 patients ⬎10 patients Percentage of polyp patients diagnosed by FOBT screening ⱕ50% ⬎50% Physician cognitive and psychological representations Uncertainty about recommending CDE Low (average score ⱕ3.5) High (average score ⬎3.5) Belief that CDE-related costs may affect utilization Low (average score ⱕ3.5) High (average score ⬎3.5) Concern about CDE-related patient discomfort and nonadherence Low (average score ⱕ3.5) High (average score ⬎3.5) Belief in the benefit of FOBT screening and follow-up Low (average score ⱕ3.5) High (average score ⬎3.5) Belief that CDE requires a lot of physican and patient time Low (average score ⱕ3.5) High (average score ⬎3.5) Belief that FOBT screening program helps in the practice of medicine ⬍100% 100%

Control (N ⫽ 198)

N

%

N

%

52 68

43.3 56.7

95 103

48.0 52.0

76 44

63.3 36.7

140 58

70.7 29.3

79 41

65.8 34.2

131 64

67.2 32.8

55 63

46.6 53.4

93 100

48.2 51.8

87 33

72.5 27.5

155 41

79.1 20.9

94 26

78.3 21.7

157 38

80.5 19.5

91 27

77.1 22.9

157 36

81.4 18.7

51 69

42.5 57.5

98 98

50.0 50.0

54 64

45.8 54.2

60 125

35.9 64.1

51 65

44.0 56.0

85 106

44.5 55.5

57 62

47.9 52.1

99 95

51.0 49.0

50 69

42.0 58.0

69 119

36.7 63.3

113 7

94.2 5.8

179 16

91.8 8.2

98 22

81.7 18.3

161 35

82.1 17.9

45 75

37.5 62.5

79 117

40.3 59.7

2 118

1.7 98.3

7 188

3.6 96.4

61 59

50.8 49.2

103 93

52.6 47.5

30 89

25.2 74.8

17 179

8.7 91.3

P value* 0.42

0.24

0.81

0.79

0.18

0.64

0.37

0.20

0.08

0.93

0.59

0.35

0.43

0.91

0.62

0.32

0.77 ⬍0.01

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MYERS ET AL.

TABLE 1—Continued Study group Intervention (N ⫽ 120)

Belief that CDE will detect colorectal cancer in ⬎5% of FOBT⫹ patients No Yes Belief that CDE will detect colorectal polyps in ⬎10% of FOBT⫹ patients No Yes Physician social support and influence Belief that CDE is standard practice Low (average score ⱕ3.5) High (average score ⬎3.5) Physician intention Intention to recommend CDE High (average score ⱕ0.4) Moderate (average score 0.4–0.8) Low (average score ⱖ0.8)

Control (N ⫽ 198)

N

%

N

%

58 61

48.7 51.3

95 96

49.7 50.3

40 78

33.9 66.1

69 124

35.8 64.3

117 3

97.5 2.5

186 9

95.4 4.6

37 55 28

30.8 45.8 23.4

46 84 67

23.4 42.6 34.0

P value* 0.86

0.74

0.34

0.14a 0.58a

a

Low intention is the reference category. * ␹ 2 test.

and belief that CDE is standard practice), we observed ceiling effects. The research team involved in the study is actively considering how to handle such items in data analysis and in use of the items in future surveys. For the current investigation, multivariable analyses are planned to identify DEM variables that predict practice CDE rates. It should be noted that in these analyses, we will take into account baseline differences between Control and Intervention Group practices (e.g., physician belief that a mail-out FOBT screening program helps in the practice of medicine). We will also assess intervention impact on DEM measures. To date, there have been few reports in the literature of studies that have used preventive health behavior theoretical frameworks to explain physician behavior. The application of behavioral theory in this study is intended to help address the need for information in this area. We hope that findings generated by this study will help to develop a deeper understanding of physician behavior and practice patterns, at least in relation to colorectal cancer screening. Finally, we awarded CME credits to participating PCPs for completing the Baseline Survey, returning ICA forms, attending academic detailing visits, and participating in the follow-up telephone call regarding CDE barriers. CME credits will also be awarded for completion of the Endpoint Survey. Providing an incentive of this type should be considered as a strategy for increasing physician participation in future studies.

APPENDIX Physician Intention to Recommend Complete Diagnostic Evaluation as Measured on the Baseline Survey

Introduction to Intention to Recommend CDE Items “Physicians may recommend different approaches for diagnostic follow-up when they talk to an FOBT-positive patient who is 50 or older about a positive screening FOBT result. Following is a series of sentences that describe different patient characteristics. Please indicate which approach to follow-up you would be most likely to recommend in each situation.” Characteristics of 10 Patients 50 or Older with a Positive Screening FOBT Result • Patient appears to be in good health. • Patient did not follow the dietary instructions while doing the FOBTs. • Patient is between 50 and 59 years of age. • Patient has a personal history of hemorrhoids. • Patient has no family history of colorectal cancer or polyps. • Patient is between 60 and 69 years of age. • Patient has fewer than three FOBT cards that are positive. • Patient has a normal hemoglobin level. • Patient was taking aspirin while doing the FOBTs. • Patient is 60 or more years of age.

COMPLETE DIAGNOSTIC EVALUATION IN COLORECTAL CANCER SCREENING

Approaches to Follow-up—Response Categories Provided • Repeat FOBT. • Barium enema alone. • Flexible sigmoidoscopy alone. • Upper GI evaluation. • Barium enema and flexible sigmoidoscopy combined. • Colonoscopy. • Other. Intention to Recommend CDE—Coding of Follow-up Response Categories • Barium enema and flexible sigmoidoscopy combined ............................ Yes • Colonoscopy ....................................................... Yes • (Barium enema and flexible sigmoidoscopy combined OR colonoscopy) AND any other approach ........... Yes • Barium enema alone AND flexible sigmoidoscopy alone ......................... Yes • All other approaches .......................................... No

8.

9.

10.

11.

12.

13.

14. 15.

ACKNOWLEDGMENTS 16. We acknowledge the contributions of Drs. John Bond, Paul Engstrom, and Arnold Kaluzny in the development of the physician intervention. In addition, we thank other research team members, including Ms. Audrey Berry, Mr. James Cocroft, Ms. Julie Diehl, Ms. Trena Diggs, Mr. Gene McGrory, Ms. Sharon Hurley, Ms. Jane Virella, and Mr. Thomas Wolf. We also express our appreciation to all of the primary care physicians who agreed to participate in The CDE Study. Finally, we thank Ms. Martha Kasper-Keintz for her editing of the manuscript.

17.

18.

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