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Recruitment of Patients Into an Internet-Based Clinical Trials Database: The Experience of OncoLink and the National Colorectal Cancer Research Alliance

From the Department of Radiation Oncology, University of Pennsylvania; Division of Gastroenterology/Department of Medicine, Department of Genetics, Abramson Cancer Center, Philadelphia, PA; and Howard Hughes Medical Institute and Ireland Cancer Center, Case Western Reserve University, Cleveland, OH

Address reprint requests to S. Jack Wei, MD, Hospital of the University of Pennsylvania, Department of Radiation Oncology, 2 Donner Bldg, 3400 Spruce St, Philadelphia, PA 19104; e-mail: wei{at}xrt.upenn.edu

	ABSTRACT

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PURPOSE: In March 2001, the National Colorectal Cancer Research Alliance (NCCRA) and OncoLink (http://www.oncolink.org) established a database to facilitate patient enrollment onto clinical trials. This study describes the population registering with the database and identifies discrepancies between individuals registering through the Internet and those registering through a telephone call center.

METHODS: Participants registered with the NCCRA/OncoLink database through the Internet or a telephone call center. All participants entering the database completed a questionnaire regarding basic demographics, colon cancer risk factors, and indicated how they became aware of the database. Comparisons were made between individuals registering through the Internet and those registering through the telephone call center.

RESULTS: A total of 2,162 participants registered during the first 16 months of the database. Most patients registered through the Internet rather than the telephone call center (88% v 12%; P < .001). More females than males registered (73% v 27%; P < .001). The majority (89%) were white. Participants registering through the Internet were younger than those registering through the call center (mean, 48.8 v 55.0 years; P < .001). There was no difference between the two groups with regard to sex or ethnicity.

CONCLUSION: The Internet has the potential to increase the likelihood that interested individuals find appropriate clinical trials. Some of the discrepancies that are known to exist for access to the Internet were also seen for those registering with the database through the Internet. Despite these differences, the potential to increase clinical trial enrollment with this type of Internet-based database is high.

	INTRODUCTION

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Carefully designed clinical trials are the gold standard for testing new cancer treatments and methods of cancer prevention, yet only 2% to 4% of all adult cancer patients participate in clinical trials.¹ The low rate of patient accrual significantly influences the statistical power of many clinical trials. In a survey of 41 randomized trials in the United States, 34% accrued less than 75% of the planned patient sample.² A number of barriers to clinical trial enrollment have been identified, including physician failure to inform patients of clinical trials. Less than half of otherwise eligible patients are considered for clinical trials by their physicians.^3–5 One of the principal reasons that physicians have not enrolled patients has been the perception that approaching a patient with a clinical trial intrudes on the physician-patient relationship.^6–10 In addition, although a patient may be eligible for a trial, physicians may not have the appropriate protocol available to enroll that patient.³ A number of patient-related factors have also been identified that have limited enrollment onto clinical trials. These factors include unwillingness to be randomly assigned to treatment,^3,7–11 time constraints, distance from treatment center (transportation),^4,9–12 insurance denial,³ distrust of the medical establishment,^7,9,12 absence of knowledge about clinical trials,⁹ and difficulty with informed consent.^7,9,10 Despite these patient-related factors, once a patient is offered enrollment onto a clinical trial, the overall rate of acceptance is 15% to 40%.^1,6,11

Increasingly, patients and physicians are using the Internet as a source of medical information. Forty percent to 50% of cancer patients use the Internet to search for health care-related information, and this number continues to increase.^13–15 However, there are concerns that access to the Internet is not equivalent for all patients. Minorities and older patients are less familiar with and have less access to the Internet.^14,15

Despite these discrepancies, the increasingly widespread use of the Internet makes it a potential source by which patients can become aware of and enroll onto clinical trials. In March 2001, the National Colorectal Cancer Research Alliance (NCCRA) established a database for individuals interested in enrolling onto clinical trials that address the prevention and treatment of colorectal cancer. Registration has been conducted through both a telephone call center and the Internet via the OncoLink Web site (http://www.oncolink.org). OncoLink is one of the oldest and largest cancer information resources on the Internet. It was established in 1994 and currently is based at the University of Pennsylvania Cancer Center (Philadelphia, PA). OncoLink has received recognition as one of the top web-based cancer resources from a number of sources, including Forbes Magazine, U.S. News and World Report, the Los Angeles Times, the Medical Library Association, and the journal Oncology, and has won in the health category of the Global Information Infrastructure awards. OncoLink currently serves 1 to 2 million pages to more than 385,000 unique Internet provider addresses each month.

The NCCRA/OncoLink database allows researchers to find patients who have expressed interest in clinical trials participation, without fear of intrusion on the physician-patient relationship. The database also allows physicians to have protocols at hand while matching patients, helping to avoid the difficulty in determining patient eligibility or finding a clinical trial that is suitable for a particular patient. This study examines the population of individuals who registered with the NCCRA/OncoLink database during its first 16 months.

	METHODS

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In March 2001, researchers from the NCCRA and OncoLink established a database for individuals interested in enrolling onto clinical trials for colorectal cancer prevention and treatment. Researchers query this database for individuals that fit enrollment criteria for clinical trials approved by the NCCRA board of scientists, allowing researchers to prescreen each participant as trials become available. The majority of NCCRA-approved clinical trials address colorectal cancer prevention; however, trials addressing cancer treatment are also available.

Individuals interested in registering with the database must first view and accept an institutional review board-approved electronic informed consent. The consent details the purpose and use of the database as well as the use of the participant's personal information. By accepting the electronic consent, participants agree to allow investigators to query the database to find potential patients who meet enrollment criteria for approved trials, and agree that investigators can contact them should they meet enrollment criteria. The electronic consent is not a surrogate for study-specific consents, which must be obtained by study investigators after seeing and evaluating the patient personally.

Registration began in March 2001 and is ongoing. Data were analyzed for individuals registering through July 2002. Registration was conducted either through a telephone call center based at the hospital of the University of Pennsylvania or through the Internet. Internet registration was conducted through the OncoLink Web site (http://www.oncolink.org) and data were held on a physically and electronically secure SQL server using secure socket layer technology.

At the time of registration with the database, participants were asked to complete a questionnaire, which was administered either by a call center operator or as part of the online registration process. The questionnaire contained questions regarding demographics, contact information, personal history of colon cancer or polyps, family history, and information concerning the method by which participants became aware of the database. The same questionnaire was administered over the Internet and through the call center. The questionnaire was designed to be interactive; therefore, individuals answered different numbers of questions as follow-up questions were asked based on responses to previous questions.

Announcement of the database was performed through several mechanisms during the first 16 months, with each announcement containing both the Web site address and telephone number for registration. Methods of announcement included a prominent notice of the registration process placed on the home page of the OncoLink Web site, a flyer distributed nationally through major pharmacies, and a segment featuring colorectal cancer prevention and highlighting the database run on a national morning television news program. This study is the initial report of the demographic information of individuals registering with the database through the Internet versus the call center.

Statistical Analysis
Statistical analyses were performed with SPSS statistical software (version 9.0 for Windows; SPSS Inc, Chicago, IL). Descriptive statistics were used to determine prevalence rates and demographic patterns of the individuals registering with the NCCRA/OncoLink database. ² or Fisher's exact tests for independence were used for comparing proportions, whereas t tests and analyses of variance were used for continuous measures. In the multivariate analysis, a logistic model was applied, and the P values of the relevant parameters were derived from the likelihood ratio test in the model. Statistical significance was defined at P .05.

	RESULTS

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Characteristics of All Individuals Registering With the NCCRA/OncoLink Database
From March 2001 to July 2002, 2,162 individuals registered with the database. Participant characteristics are shown in Table 1. More females registered than males (73% v 27%; P < .001). The vast majority registering were white (88.9%). The median age of the database population was 49 years (mean, 49.6 years; range, 18 to 101 years). The majority of participants (59%) had undergone some type of colorectal cancer screening (ie, colonoscopy, sigmoidoscopy, fecal occult blood testing) before registration. The majority of participants became aware of the database from the television news segment (33.6%) or while surfing the OncoLink Web site (21.1%; Table 2). The television news segment was the most common method by which patients became aware of the database, whether the patient registered through the Internet or through the call center (Table 3).

There was also a significant difference between the two groups regarding the method by which they became aware of the database (P < .001). On univariate analysis, individuals registering through the Internet were more likely to have become aware of the database while surfing the OncoLink Web site (P < .001) and through other sources (P = .001), whereas those registering through the call center were more likely to have heard about the database through the television news segment (P < .001). On multivariate analysis, age was found to be significantly different between the two groups (P < .001). Multivariate analysis also showed significant differences between the two groups with regard to the likelihood that participants became aware of the database through the television news segment, by surfing the Internet, through family and friends, or through other sources. There was no difference on multivariate analysis between the two groups with regard to sex or ethnicity.

It is not surprising that individuals surfing the OncoLink Web site overwhelmingly elected to register through the Internet. This difference potentially biases the comparisons of the other sources by which the database was announced. To determine more accurately the method by which patients became aware of the database, a separate analysis of announcement sources excluding the OncoLink Web site was performed. In this analysis, individuals registering through the Internet were more likely to have become aware of the database through news articles (P = .007), through family and friends (P = .007), and other sources (P < .001). However, there was no difference between the two groups with regard to the likelihood that they became aware of the database through the television news segment.

	DISCUSSION

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Enrollment onto clinical cancer trials is critical to the advancement of cancer treatment and prevention, yet remains exceedingly low.^1,2 In an effort to facilitate patient enrollment onto clinical trials, the NCCRA and OncoLink have established a national database for individuals interested in enrolling onto clinical trials for colorectal cancer prevention and treatment. An important component of the database has been the ability to register via the Internet, taking advantage of the growing number of individuals who use the Internet to search for health care-related information. This study is the first in the United States to describe the population of individuals registering in this type of database and the first to identify potential discrepancies in the populations of individuals enrolling through the Internet compared with those who registered through an alternative, non-Internet-related method.

Barriers to clinical trial enrollment can be divided broadly into two categories: patient-related barriers and physician-related barriers. Patient-related barriers include unwillingness to be randomly assigned to treatment,^3,7–11 time constraints, distance from treatment center (transportation),^4,9–12 insurance denial,³ distrust of the medical establishment,^7,9,12 absence of knowledge about clinical trials,⁹ and difficulty with informed consent.^7,9,10 Physician-related factors include disagreement with trial design,^8,9,16,17 lack of time,^10,16,17 lack of resources for follow-up,^10,18,19 unwillingness to randomize treatment,^6,8 excessive financial burden,^9,16,17 difficulty with informed consent,^6,9,16 lack of available protocol,³ and infringement on the physician-patient relationship.^6–10 Although patient-related factors undoubtedly affect the rate of participation in clinical trials, these factors are often secondary to physician-related factors, particularly physicians' recommendation for enrollment onto a trial.^17,18 Only 2% to 4% of adult cancer patients enroll onto clinical trials compared with more than 70% of pediatric cancer patients.^1,20,21 Although part of this discrepancy is due to the more rigid eligibility criteria of adult cancer trials compared with pediatric trials, the willingness of physicians to offer and enroll adult patients onto clinical trials plays a critical role in this difference.^19,22 This is demonstrated by the fact that when an adult patient is offered enrollment onto a clinical trial, the rate of enrollment is 15% to 40%.^1,6,11

The NCCRA/OncoLink database potentially circumvents several of the most commonly cited physician-related barriers to clinical trial enrollment, including lack of knowledge of appropriate clinical trials, unwillingness to randomly assign patients, and fear of infringement on the patient-physician relationship. Lara et al³ showed that although 62% of patients in their study were considered for clinical trials, 47% of those considered could not be enrolled because the physician did not have the appropriate protocol available. Lack of knowledge of appropriate protocols is even higher in community- and rural-based practices. In one study, only 26% to 43% of physicians were aware of any formal oncologic clinical trials before the institution of programs specifically designed to educate physicians regarding trials.²³ When physicians are aware of trials for which their patients are eligible, they are significantly more likely to refer patients for enrollment. The NCCRA/OncoLink database allows physicians to find patients who are eligible for enrollment, decreasing the need for individual physicians in the community to be aware of these protocols for enrollment to occur. It is unlikely that researchers querying the database would have personal concerns about patient randomization, which may prevent some physicians from enrolling an otherwise interested patient. Because all patients who have registered with the database have indicated that they are interested in being contacted regarding potential enrollment onto a clinical trial, there is little fear of infringing on the physician-patient relationship. By circumventing these physician-related barriers, the database increases the chances that eligible and interested patients will find an appropriate clinical trial.

To increase the rate of registration, the NCCRA/OncoLink database takes advantage of the increasingly widespread use of the Internet. The Pew Internet and American Life Project reported in December 2003 that 63% of adults in the United States were using the Internet.²⁴ The Internet is the most commonly used nonphysician source for health care information, with 40% to 50% of patients searching the Internet for health care-related information.^{13–15,25–27} This high rate of Internet use provides an avenue by which a large number of patients can be informed of and register with the database. Importantly, the Internet provides a method of contacting eligible individuals who otherwise may not have been contacted because their physicians lack interest in or knowledge of clinical trials. At the time this database was developed, it was not known if individuals would be willing to register with the database through the Internet. Patients have previously voiced concern about the ability to protect the privacy of their personal health information over the Internet.^28,29 Over the period analyzed, 88% of the individuals who registered elected to do so through the Internet. The willingness, and in fact preference, of participants to register through the Internet indicates that concerns about the protection of private information did not affect individuals' willingness to register through the Internet.

Historically, several subsets of patients have enrolled onto clinical trials at an even lower rate than the general population. Enrollment of older patients has lagged behind that of other patients.^5,30,31 Minority enrollment has also been lower, primarily due to lower willingness of African American patients to enroll onto clinical trials.^32–35 Under-representation of older patients and minority patients limits the ability to generalize the results of many clinical trials. Similar populations seem to be underserved with regard to Internet usage. Older patients are less likely to have access to or use the Internet.¹⁴ Minorities and patients receiving their care from nonacademic or community-based hospitals also lag behind the general population with regard to Internet access and use.^14,15 Such a discrepancy can potentially bias the population registering through the Internet, subsequently biasing the population enrolling onto clinical trials through the database.

In this study, there was no difference with regard to ethnicity between those enrolling through the Internet and those who did not. Minorities, particularly African Americans, are more reluctant to enroll onto clinical trials and are more likely to cite distrust of the medical establishment as a reason for not enrolling onto clinical trials.^33,35–38 Presumably, minorities who have actively found and registered with the NCCRA/OncoLink database are more willing to enroll onto clinical trials. Nevertheless, only 11% of individuals who registered with the database were minorities, a rate that is lower than that seen for minority enrollment onto cancer treatment trials at the National Cancer Institute.²¹ In particular, only 3.4% of individuals registering with the database were African American and only 2.3% were Hispanic. The low rate of minority accrual through both the Internet and the telephone call center may indicate a general unwillingness of minority individuals to register with this type of database. It should be noted that a relatively higher proportion of African Americans elected to enroll through the call center. Twenty-four percent (18 of 74) of African Americans registering elected to do so through the call center, compared with 11% (220 of 1,921) of whites. Although this difference may indicate a relative reluctance of African Americans to enroll through the Internet, it may simply reflect the lower rate of Internet access of African Americans. Despite this difference, more than three fourths of African Americans registering with the database elected to do so through the Internet.

Although ethnicity did not significantly affect the likelihood of registering through the Internet, individuals registering through the Internet were significantly younger than those registering through the call center. This parallels the lower rate of Internet access of older patients.^14,15 Despite the low rate of older individuals registering through the Internet, a significant number of individuals older than the age of 49 years did register via the call center. These individuals may potentially increase clinical trial enrollment of under-represented, older populations, and efforts to increase awareness of the database that include information on registering through the call center may further increase registration of older individuals into the database.

Interestingly, there were significantly more women registering with the database than men. Women have been found to search the Internet for general health information more than men.¹⁴ The higher rate of women registering with the database may be a result of this discrepancy. Although more women registered overall, the relative proportion of women and men registering through the Internet was equal (88% for both genders). The high rate of women registering and the preference of all participants to register via the Internet indicate that databases using the Internet can be used to increase the likelihood that clinical trials aimed at women are found by interested female participants.

Despite the potential benefits of the database, there is a distinct risk of recruiting a biased population into the database. Healthy volunteer patients frequently do better than nonvolunteers, and enrollment onto clinical trials of patients who voluntarily registered into the NCCRA/OncoLink database can possibly result in a selection bias.^39–41 In addition, it is important to note that the majority of individuals in this study neither have cancer nor have high-risk features (such as colonic polyps or family history) for cancer development. However, the majority of open NCCRA trials address cancer prevention. Given the recommendation that individuals 50 years and older undergo colon cancer screening, the population of individuals registering with the database is appropriate for the types of trials that are available through the NCCRA.⁴²

It is also important to note that this study does not address the rate of actual trial enrollment from individuals registering through the Internet. It is possible that individuals who enroll onto a trial as a result of registration with the database would have enrolled onto a trial regardless. However, it is unlikely that all individuals who enroll onto a trial due to registration with the database would have done so without it. Because individuals must actively seek out and enroll onto the database, it is unlikely that all individuals who registered have previously been approached for clinical trial enrollment or are currently enrolled onto a trial. It is more likely that individuals registered with the database because they were interested in clinical trial participation but had not yet had the opportunity to enroll.

Overall, the potential for registries that use the Internet is high. Through the database, clinical researchers can access a pool of individuals who have already expressed interest in enrolling onto clinical trials, avoiding a number of the physician-related barriers to clinical trial enrollment. In addition, registration using the Internet potentially allows researchers to contact individuals who otherwise would not have access to clinical trials. Internet registration does not appear to affect the percentage of minority patients registering and may improve the rates of clinical trial enrollment of women. Future studies will address the potential population differences of patients learning about clinical trials through the Internet compared with those learning of trials through health care providers in the clinic. As this database matures and more clinical trials are added, future studies will also investigate how the Internet can influence actual enrollment rates of clinical trials. On the basis of the results of this database, OncoLink has designed and launched a clinical trials matching service for all cancer diagnoses.

	Authors' Disclosures of Potential Conflicts of Interest

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The authors indicated no potential conflicts of interest.

	Acknowledgment

 
We thank the Today Show (NBC) and Katie Couric for their help in reaching individuals for entry onto the database, and Rosemarie Mick for advice on the statistical analysis of this study.

	NOTES

 
Supported by OncoLink and the National Colorectal Cancer Research Alliance. Funded in part by the NCCRA and Entertainment Industry Foundation, and the Hanson Foundation.

Authors' disclosures of potential conflicts of interest are found at the end of this article.

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TOP ABSTRACT INTRODUCTION METHODS RESULTS DISCUSSION Authors' Disclosures of... REFERENCES

 
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Submitted July 21, 2003; accepted September 3, 2004.

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This Article Abstract Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Save to my personal folders Download to citation manager Rights & Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Wei, S.J. Articles by Rustgi, A.K. Search for Related Content PubMed PubMed Citation Articles by Wei, S.J. Articles by Rustgi, A.K. Social Bookmarking                            What's this?