Barriers to participation in randomised controlled trials: a systematic review

Factors motivating dyspepsia patients to enter clinical research

One of the most influential factors in science and medicine has been the development of placebo-controlled clinical trials. However, recruitment of patients for clinical trials is sometimes a major problem in clinical research. Successful patient recruitment may be enhanced with a clear understanding of the motivating factors that determine a patient's decision to enter a study. We have developed the Patients' Expectations, Attitudes and Knowledge (PEAK) Program consisting of questionnaires designed to study the factors motivating patients to enter a clinical trial, as well as capturing the experiences of research participants. A total of 247 female patients with dyspepsia (mean age: 43.9; range: 18.0-78.0 years) who entered either of two prospective double-blind, randomized, placebo-controlled multicenter trials in the USA completed PEAK Entry questionnaires during the first study visit. Based on their responses, the top three factors motivating patients to join the clinical trial were: interest in receiving investigational treatment with average score (AS) of 4.33 +/- 0.08 (M +/- SEM) on a 5-point scale, possibility of getting skilled professional care (AS = 4.07 +/- 0.09), and altruism expressed as an intention to help develop a new drug for the sake of other people (AS = 3.89 +/- 0.09). Age, ethnicity, and educational status significantly affected motivational factors of patients. These results indicate that recruitment can be enhanced by targeting these motivations in physician/patient communications, informed consent process and advertising for study participants.

Recruitment of patients for a clinical trial: factors on the physician side and reasons on the patient side

OBJECTIVES

To examine the factors related to actual patient recruiters among the physicians who initially agreed to collaborate in a randomized control trial.

METHODS

We conducted a questionnaire survey of 679 physicians (512 actual recruiter and 167 non-recruiters) who had initially agreed to recruit patients for a clinical trial to determine factors to predict who would actually do so.

RESULTS

Response rates among recruiters and non-recruiters were 87.5% and 73.1%, respectively. Multivariate logistic regression model showed that the proportions of regular users of computer [odds ratio (OR) =2.1, 95% confidence intervals (CI)=1.3-3.3] (p=0.002) and current participants in other clinical trials (OR=2.2, CI=1.5-3.4) (p=0.001) were significantly higher among recruiters than non-recruiters. Patients' reasons for non-participation as perceived by the physicians did not differ between recruiters and non-recruiters.

CONCLUSION

Results of this study might be useful in predicting actual recruiters at the outset of clinical trials.

Parents' perspectives on research involving children

Children's participation in research is essential for the development of safe and age-appropriate treatments. However, children's participation is limited. The aim of this study was to determine (1) mothers' and fathers' views on which agencies/persons should evaluate the level of acceptable risk for children and (2) parents' willingness to allow children to participate in research. Medical factors, sociodemographics, and research attitudes were related to willingness. The study used a cross-sectional and longitudinal design with 863 expectant parents (435 women; 428 men) consecutively recruited at gestational week 19 during routine ultrasound examination at 2 hospitals in Uppsala County, Sweden. 123 women at gestational week 34 were followed-up. Parental ratings of agencies/persons' degree of involvement in risk-evaluation for. child research participants and parents' willingness to allow children to participate in research were the main outcome measures. Most parents believed that more pediatric research was needed. Attitudes played a major role in willingness, indicating a potential for information that could modify willingness. Over 80% of mothers and fathers rated the attending physician as needing to be "fully involved" in risk evaluation for research participants. Parents' views contradict current trends in research ethics which place evaluation of risk in the hands of regional agencies. Instead, the majority of parents would like the decision to be individually based on the attending physicians advise. We conclude that children's participation in research could be improved by actively incorporating the attending physician and by educating the public so that research attitudes can be based on accurate information.

A survey on patient educational needs in irritable bowel syndrome and attitudes toward participation in clinical research

BACKGROUND

The educational needs of patients with irritable bowel syndrome (IBS) are poorly understood and rarely studied.

AIM

To determine the educational needs of IBS patients, regarding content, presentation format, and expectations from healthcare providers.

METHODS

Fifteen functional GI clinic patients were asked open-ended questions to generate items for a questionnaire addressing the study aim. A total of 104 IBS patients received this questionnaire by mail (42 had declined to participate in a prior IBS study). To assess the frequency of endorsements and importance (on a scale of 1-3) of the items, an index was calculated (frequency of endorsements x mean rating per item, first priority scored 3, third priority scored 1). A higher index indicated greater endorsement based on frequency and rating of response.

RESULTS

A total of 29 (28%) subjects (22 willing, 7 unwilling to participate previously in questionnaire research) completed the questionnaire (mean age, 42.6 years; SD, 14.2 years; 19 female, 10 male). The overall low response rate is likely related to the population studied; 40.4% of our study subjects have declined participation in prior research. The response rate of those who have previously agreed to participate was 36%. The typical response profile included: interest in learning disease management (index=1.4) and preference for information presented in person by an M.D. (2.4). Choice of presentation media included magazines (1.9), television (1.5), and Web sites (1.2). Doctors' qualities ranked high related to competency (0.8), allocation of sufficient time (0.7), and listening skills (0.4). Preferred incentives for research participation included a thank you note (0.4), summary of trial results (0.3), and monetary incentives (0.6).

CONCLUSIONS

This qualitative study will provide pilot data for a national survey on the educational needs of IBS patients, for use in developing effective patient-centered, educational programs.

Barriers to participation in HIV drug trials: a systematic review

The enrolling of adequate participants into HIV experimental drug trials presents an important challenge. We systematically reviewed the literature to identify barriers and concerns amongst HIV patients to participation in HIV clinical drug trials. We reviewed studies for validity and content, and generated pooled estimates of the frequency with which patients identified particular issues by pooling across studies that presented results as proportions. We included three semi-structured interview studies, two open-ended questionnaires, and nine quantitative studies. Major barriers to participation included fear of side-effects, distrust of researchers, general concerns about research design, interference in everyday life or changes in routine, and social discrimination. Results from the quantitative studies indicated that the most prevalent barriers were as follows: suspicions about the drug itself (53%, 95% CI 24-83%), patients were not informed or believed they were not eligible (38%, 25-50%), and travel or transport obstacles (39%, 21-57%). The findings of this study should aid drug trialists in developing strategies to maximise participation and cooperation in HIV clinical drug trials while adequately informing and protecting prospective participants.

Reasons for participation and non-participation in a randomized controlled trial: postal questionnaire surveys of women eligible for TOMBOLA (Trial Of Management of Borderline and Other Low-Grade Abnormal smears)

BACKGROUND

Better understanding of motivators for, and barriers to, participation in randomized controlled trials (RCTs) in different study populations and settings has the potential to improve participation of historically under-represented groups (eg, women) in future trials.

PURPOSE

To investigate reasons why women agreed, or declined, to participate in a RCT.

METHODS

In two postal questionnaire-based studies, we investigated women's reasons for participation or non-participation in TOMBOLA, a RCT comparing management policies for low-grade cervical abnormalities. Four-hundred and ninety-two TOMBOLA participants (response rate 56%) completed questionnaires on reasons for participation. One-hundred and thiry-seven women (38%) who declined TOMBOLA participation completed questionnaires on reasons for this.

RESULTS

Eighty percent of women reported that one of their reasons for attending their TOMBOLA recruitment appointment was worries about their smear result. Ninety-four percent participated in the RCT because it was a worthwhile contribution to the cervical screening programme and other women; for 70% this was the most important reason. These proportions did not vary by socio-demographic factors. Thirty-two percent thought participation would result in better care. The most common reason for non-participation was preference for follow-up from the woman's GP. Logistical issues (eg, inconvenient appointments, travel time, arranging time off work or child-care) were commonly cited. Fourteen percent were too frightened to participate; this was unrelated to the grade of the recruitment smear.

LIMITATIONS

Response rates were not high, but there was little evidence of response bias. Structured questionnaires were used.

CONCLUSIONS

Future research should address how best to deliver information to ensure different social groups appreciate potential benefits of RCT participation and provide reassurance regarding fears about participation. Simple strategies (eg, appealing to the altruism of potential participants or offering flexible recruitment clinic locations and times) might enhance RCT recruitment rates. This in turn would ensure best use of research resources thus bringing the greatest benefits to participants and the population.

Marital status, treatment, and survival in patients with glioblastoma multiforme: a population based study

BACKGROUND

Social factors influence cancer treatment choices, potentially affecting patient survival. In the current study, the authors studied the interrelations between marital status, treatment received, and survival in patients with glioblastoma multiforme (GM), using population-based data.

METHODS

The data source was the Surveillance, Epidemiology, and End Results (SEER) Public Use Database, 1988-2001, 2004 release, all registries. Multivariate logistic, ordinal, and Cox regression analyses adjusted for demographic and clinical variables were used.

RESULTS

Of 10,987 patients with GM, 67% were married, 31% were unmarried, and 2% were of unknown marital status. Tumors were slightly larger at the time of diagnosis in unmarried patients (49% of unmarried patients had tumors larger than 45 mm vs. 45% of married patients; P = 0.004, multivariate analysis). Unmarried patients were less likely to undergo surgical resection (vs. biopsy; 75% of unmarried patients vs. 78% of married patients) and were less likely to receive postoperative radiation therapy (RT) (70% of unmarried patients vs. 79% of married patients). On multivariate analysis, the odds ratio (OR) for resection (vs. biopsy) in unmarried patients was 0.88 (95% confidence interval [95% CI], 0.79-0.98; P = 0.02), and the OR for RT in unmarried patients was 0.69 (95% CI, 0.62-0.77; P < 0.001). Unmarried patients more often refused both surgical resection and RT. Unmarried patients who underwent surgical resection and RT were found to have a shorter survival than similarly treated married patients (hazard ratio for unmarried patients, 1.10; P = 0.003).

CONCLUSIONS

Unmarried patients with GM presented with larger tumors, were less likely to undergo both surgical resection and postoperative RT, and had a shorter survival after diagnosis when compared with married patients, even after adjustment for treatment and other prognostic factors.

Trials and tribulations: understanding motivations for clinical research participation amongst adults with cystic fibrosis

In the context of understanding motivations for clinical research participation, many authors consider issues such as informed consent and how patients perceive the research method and process. However, many investigations focus only on one method of research, most commonly the randomised controlled trial. Understanding how chronically ill members of one specific patient group respond to all requests for research participation are rare. Cystic fibrosis (CF), a genetic condition whereby those affected are used to taking a wide array of treatments and attending a specialist care centre over many years, and are generally knowledgeable about their condition, represents an ideal case for investigating how staff requests for clinical research participation are accepted or declined. Using Bloor's systems of relevance framework for risk behaviour and risk reduction, specialist CF centre patients' motivations for participation or non-participation in clinical research can be understood. The framework takes into account two sets of conceptual oppositions: habituation and calculation, constraint and volition. These oppositions represent a range along a continuum of risk behaviour rather than being absolute distinctions. Decisions to participate are influenced mainly by the patient's state of health at the time of request, the nature of the trial and the social context within which sufferers are placed. Understanding why chronically ill patients refuse some requests and yet accept others may assist researchers in designing protocols that take these factors into account and achieve the desired numbers of participants whilst protecting those in vulnerable positions.

Recruitment to a trial of self-care skills training in long-term health conditions: analysis of the impact of patient attitudes and preferences

The rise of evidence-based practice has highlighted the importance of effective recruitment to randomised controlled trials if studies are to be adequately powered and valid. However, there are also increasing concerns about patient preferences and choice within trials. The current authors are involved in a trial of a programme to provide self-care skills training for people with long-term health conditions (the 'Expert Patients Programme'), and during the design stage there were significant concerns about the impact of patient preferences on the feasibility and validity of the study, because recruitment required that patients risk randomisation to a waiting list control group. This paper first details the issues raised in this trial, and the methods used to attempt to overcome them. Data on recruitment rates, loss to follow up and patient decision making about participation are presented, which suggested that initial assumptions about the impact of patient preferences were incorrect. Key lessons concerning preferences in this patient population and related issues in trial administration are then discussed.

Non-enrolment of ovarian cancer patients in clinical trials: reasons and background

BACKGROUND

Some retrospective analyses have suggested that participation in clinical trials is associated with better outcome. However, it is not clear to what extent selection bias contributes to this observation.

PATIENTS AND METHODS

We evaluated the reasons for non-enrolment of ovarian cancer patients in clinical trials. All patients with ovarian cancer not enrolled in clinical studies and treated in 2001 in the participating centres were documented retrospectively and compared with patients enrolled in clinical trials at the same institutions during the same time period.

RESULTS

Two hundred and seventy-four patients with advanced ovarian cancer (FIGO stage IIB-IV) were included, of whom 139 (51%) and 135 (49%) patients were enrolled in this study and in prospective clinical trials, respectively. Ninety-four of 274 patients (34%) did not meet the inclusion criteria for clinical trials. Of 180 eligible patients, 28 (16%) refused participation and a further 17 patients (9%) were not recruited although they met the inclusion criteria. The non-study patients were older (66.7 versus 57.2 years; P <0.0001), underwent less radical surgery (hysterectomy, oophorectomy and omentectomy performed: 61.2% versus 80.7%; P = 0.001; rate of lymphadenectomy 30.9% versus 45.2%; P = 0.015) and more frequently had bulky residual disease (residual disease >2 cm: 36.2% versus 20%; P = 0.016). However, 62% of the non-study patients were treated with the same chemotherapy as in the standard arm of the respective clinical studies.

CONCLUSIONS

Study patients differ substantially from non-study patients, thus hampering generalisation of study results. Our results suggest that at least some inclusion criteria for clinical trials should be modified to increase study participation without compromising safety.

South Asian participation in clinical trials: the views of lay people and health professionals

There is little UK-based empirical research on South Asian participation in clinical trials. The predominantly US literature rarely engages with mainstream debates about ethnicity, diversity and difference. This study was prompted by a lack of knowledge about how South Asian people perceive trial involvement and the risks and benefits involved. Face to face interviews were conducted with 25 health professionals (consultants, GPs, nursing staff, academics, non-medically trained trial co-ordinators, LREC and MREC members) and 60 South Asian lay people (20 Indians, 20 Pakistanis and 20 Bangladeshis) who had not taken part in a trial. The study took place in the Leeds and Bradford areas of England. It was found that lay South Asian attitudes towards clinical trial participation focused on similarities rather than differences with the general UK population, suggesting that the relevance of ethnicity should be kept in perspective. There was no evidence of antipathy amongst South Asians to the concept of clinical trials, and awareness was a correlate of social class, education and younger age. Lay factors that might affect South Asian participation in clinical trials included: age; language, social class; feeling of not belonging/mistrust; culture and religion. Approachable patients (of the same gender, social class and fluent in English) tended to be 'cherry picked' to clinical trials. This practice was justified because of a lack of time, resources and inadequate support. South Asian patients might be systematically excluded from trials due to the increased cost and time associated with their inclusion, particularly in relation to the language barrier. Under-representation might also be due to passive exclusion associated with cultural stereotypes. The paper concludes by applying the theoretical framework of institutional racism as a means of making sense of policy and practice. At the same time, caution is advocated against using ethnicity as the only form of discrimination facing minority ethnic populations.

Clinical trial participants compared with nonparticipants in cystic fibrosis

RATIONALE

The randomized clinical trial has been an important tool for expanding our knowledge of disease. This study is the first to compare trial participants to the entire eligible population.

METHODS

We performed a cohort analysis using data from the Cystic Fibrosis Foundation Registry database between 1992 and 1998.

MEASUREMENTS AND MAIN RESULTS

There were 8,735 patients older than 6 yr followed for the entire period. Of the patients, 2,635 patients (30.2%) were enrolled in at least 1 of 32 Institutional Review Board-approved clinical trials, with an average annual participation rate of 7%. Patients enrolled in clinical trials had more advanced disease as judged by FEV(1)% predicted (68 vs. 77%, p < 0.001), higher rates of Pseudomonas aeruginosa infection (71 vs. 65%, p < 0.01), and were more likely to have private insurance (odds ratio [OR], 1.25; 95% confidence interval [CI], 1.14-1.37) and be white (OR, 1.98; 95% CI, 1.44-2.70). No sex differences were noted. Despite the worse clinical status at baseline, clinical trial participants had a lower average annual rate of decline in lung function (1.33%/yr; 95% CI, 1.20, 1.46; compared with 1.52%; 95% CI, 1.43-1.60).

CONCLUSIONS

These results show that the overall participation rate is very high. Despite more advanced disease at baseline, lung function decline was lower in trial participants; the cause of this difference is unclear. The differences seen in insurance status are concerning. Efforts should be made to ensure adequate representation from different social demographic groups.

An assessment of willingness to participate in a randomized trial of arthroscopic knee surgery in patients with osteoarthritis

Identifying barriers to recruitment into a randomized clinical trial can help researchers adjust recruitment strategies to maximize enrollment. To determine barriers to enrollment of patients in trials of knee osteoarthritis treatments, we recruited from three centers patients over age 45 who had both knee osteoarthritis and a meniscal tear. We described a hypothetical randomized trial of arthroscopic partial meniscectomy versus non-operative management and assessed patients' willingness to participate in such a trial. We elicited preferences for treatment along with information on age, sex, education level, race, work status, and pain. We examined the association between these factors and willingness to participate in the trial. Orthopedic surgeons identified 106 eligible osteoarthritis patients, of whom 12 could not be reached, 6 refused and 88 (83%) completed interviews. 63% were female, 55% were college graduates, 23% were non-white and mean age was 60+/-8. The mean WOMAC pain score was 56+/-23. 22% of patients stated that they were definitely willing to participate in the hypothetical trial, and 24% stated they were probably willing. Subjects lacking strong preferences for treatment stated a greater willingness to participate than those with strong preferences (36-14% definitely willing, chi(2) for trend, p=0.005). WOMAC pain score, age, education, work status and race were not associated with willingness to participate. Males were more likely than females to state a willingness to participate (39-11% definitely willing, p=0.005). Since OA affects females disproportionately, a better understanding of barriers to females' participation in trials may enhance future research on treatment of osteoarthritis. Effectively addressing a priori treatment preferences through patient education about the advantages and drawbacks of treatments may increase willingness to participate in trials.

Volunteer human subjects' understandings of their participation in a biomedical research experiment

The paper focuses on how volunteer human subjects in research understand their own participation in experimentation. We ask how they view their own role, the experimental setting, and how they articulate their understanding of the researcher-subject relationship. The empirical basis of the study is participant-observation and qualitative semi-structures interviews with volunteers in an experimental setting far removed from the more commonly studied randomised control trial (RCT), namely, the early stage testing of a prototype instrument for breast imaging. Analysis of this empirical data leads us to conclude that research subjects do not conform solely to one or other of the models of the researcher-subject relationship suggested in the literature. Rather, the interaction needs to be considered as a social situation which volunteer subjects actively negotiate in real time. They move through multiple roles and identities as part of the navigation through unfamiliar social territory, in order to establish a relationship in which they can feel socially comfortable and appropriately valued.

The impact of the physician on the accrual to randomized clinical trials in patients with primary operable breast cancer

Randomized clinical trials (RCT) are the best way to define optimal treatment, but the accrual rates for hardly any trials have been reported. We analyzed retrospectively the participation of patients in eight phase III multicenter RTCs. Out of a total of 738 patients treated in a single institution for operable breast cancer over a 3-year period, 455 patients (62%) were eligible for at least one of the ongoing trials. Overall, 81% of the patients were informed and 47% of the eligible patients consented to participate. The accrual was 100% to a study with an aggressive combined modality treatment arm for patients with a poor prognosis. A low accrual rate was seen in two trials: 6% in the "elderly" trial comparing tamoxifen only with mastectomy and 10% to the "axilla" trial comparing surgery with radiotherapy to the axilla. The clinicians failed to inform most of these patients about the two trials. In the literature seven of the eight trials were reported; two of them (29%) failed to accrue enough patients.

Enrolling older persons in cancer trials: the effect of sociodemographic, protocol, and recruitment center characteristics

PURPOSE

To determine the effect of patient, protocol, geographic, and institutional factors on enrollment of older persons onto cancer trials.

METHODS

We conducted a cross-sectional analysis of patients enrolled onto National Cancer Institute-sponsored lung, breast, colorectal, and prostate cancer trials during 1996 to 2002. We used a cross-classified logistic multilevel model to examine the associations between patient, hospital, county, and protocol characteristics, and the likelihood of participants being elderly (>or= 65 years old).

RESULTS

The final study sample consisted of 36,167 patients enrolled onto 33 trials. After accounting for cancer type, only 6% of the variation in elderly enrollment onto cancer trials was at the protocol level. In contrast, more than 55% of the variation in elderly enrollment was attributable to patient level variation. In multivariate analysis, nonwhite patients were significantly less likely to be elderly than whites (odds ratio [OR] for blacks, 0.51; 95% CI, 0.44 to 0.58; and OR for Hispanics, 0.49; 95% CI, 0.40 to 0.59 v whites). Participants living less than 7 miles from their recruitment center were significantly more likely to be elderly (OR, 1.31; 95% CI, 1.24 to 1.38). Among the 910 recruitment centers, the median adjusted proportion of patients who were elderly was 24.9% (interquartile range, 24.0% to 26.9%). There were a significantly higher number of outlier centers (or= 29.3% elderly) than would be expected by a normal distribution (68 observed v six expected; P < .0001).

CONCLUSION

Race and proximity to trial enrollment centers were significantly related to age of trial participants after adjusting for protocol factors. Additional work should explore why some recruitment centers were outliers regarding enrollment of older persons.

An Internet-based cancer clinical trials matching resource

Background

Many patients are now accessing the Internet to obtain cancer clinical trials information. However, services offering clinical trials recruitment information have not been well defined.

Objectives

This study describes one of the first Web-based cancer clinical trials matching resources and the demographics of users who were successfully matched.

Methods

OncoLink is the Internet-based educational resource managed by the University of Pennsylvania Cancer Center (UPCC) and serves between 1 and 2 million pages per month to over 385000 unique IP addresses. OncoLink launched one of the first clinical trials matching resources on the Internet that allowed patients to enter demographic data through a secure connection and be matched to clinical trials. For patients with matches to potential trials, appointments were facilitated with the principal investigators.

Results

While we did not keep track of patients who could not be matched, 627 patients who submitted online applications between January 2002 and April 2003 were successfully matched for potential enrollment in clinical trials. The mean age of the patient population was 56 years (range 18–88 years). Males represented 60% of the patient population, and over 90% of users were Caucasian. Most of the applications were from patients with colorectal cancer (13%), lung cancer (14%), melanoma (10%), and non-Hodgkin's lymphoma (9%).

Conclusions

This report shows that a significant number of patients are willing to use the Internet for enrolling in clinical trials. Care must be taken to reach patients from a variety of socioeconomic and racial backgrounds. This Internet resource helps to facilitate a consultation with a cancer patient who is prescreened and motivated to enroll in clinical trials.

The feasibility of a randomised, placebo-controlled clinical trial of homeopathic treatment of depression in general practice

Depression is common in general practice and lack of concordance is an important problem in its treatment. Homeopathy has few side effects and is generally associated with good compliance. We report a study investigating the feasibility of a trial to compare the effectiveness of homeopathy with a conventional antidepressant and placebo.

OBJECTIVES

To assess the feasibility of a general practice-based clinical trial comparing the effectiveness of individualised homeopathic treatment vs Fluoxetine (Prozac) vs placebo in the treatment of major depressive episodes of moderate severity.

DESIGN

Randomised, double-dummy, double-blind parallel group clinical trial.

SETTING

Lower Clapton Group Practice, East London.

METHOD

Patients were recruited through their general practitioners as they presented during a 9 month period. Recruitment target was 30 patients. Eligibility was confirmed by a consultant psychiatrist using standard criteria (DSM-IV) and instruments Hamilton Depression Scale (HAMD). Suicidal and psychotic patients were excluded, additional precautions against suicide were incorporated. There was a 1 week run-in period and patients showing spontaneous improvement were excluded. Homeopathic treatment was prescribed by a GP qualified in homeopathy, from a 'limited list' of 30 homeopathic medicines, with the help of decision support software. Patients were randomised to receive verum Fluoxetine and placebo homeopathy, or verum homeopathy and placebo Fluoxetine, or placebo homeopathy and placebo Fluoxetine. Treatment duration was 12 weeks. The outcomes were: adverse drug reactions, clinical global impression (CGI); HAMD; mini international psychiatric Interview; Pittsburgh sleep quality index; Side-effects checklist; Short Form 12; treatment credibility questionnaire; work and social disability scale. The primary outcome measures were HAMD and CGI.

RESULTS

A recruitment calculation indicated that over 230 suitable patients would be expected to attend the practice during the recruitment phase. Thirty one patients were referred for possible inclusion in the trial by their GPs. Twenty three met the entry criteria, 11 were randomised and 6 completed the study. Of the completers, one received homeopathy, 2 placebo and 3 Fluoxetine.

CONCLUSIONS

A trial of this design in general practice is not feasible, because of recruitment difficulties, many of them linked to patient preference. Different approaches are required to recruit adequate patient numbers to trials of this sort.

Physicians' attitudes towards and reasons for participation in the Candesartan Antihypertensive Survival Evaluation in Japan (CASE-J) trial

BACKGROUND: Physicians’ perception and attitudes towards a research topic and trial management could influence their participation in a randomized controlled trial. The objectives of this study were to determine the reasons for physicians’ participation in and attitudes towards the Candesartan Antihypertensive Survival Evaluation in Japan (CASE-J) trial.

METHODS: CASE-J’s main objective is to compare the effectiveness of an angiotensin II receptor antagonist (candesartan cilexetil) with that of a calcium channel blocker (amlodipine besilate) in terms of the incidence of cardiovascular events among high-risk hypertensive patients. We conducted a questionnaire survey among the physicians (n=512) participating in that trial to determine the reasons behind their participation and to elicit their reactions to the trial management.

RESULTS: Eighty-eight percent of the 512 participating physicians responded to our survey. The main reasons for participation were clear objectives of the trial (85.1%), a simple protocol (61.1%), interest in finding out the inhibiting effects of the drugs on cardiac events (80.2%), and a well-organized support system (59.8%). As for negative factors, case registration and follow-up were considered cumbersome by 28.6% and 10.8%, respectively while 44.2% stated that support by the clinical research coordinators provided by the trial management authority was necessary for case screening, recruitment process, patient registration, and follow-up. Multivariate logistic regression analysis showed that participants who did not use a computer very regularly (odds ratio = 1.9, 95% confidence interval = 1.1-3.6) were more likely to consider the case registration and follow-up procedures as a cumbersome.

CONCLUSION: The information generated by this study could be useful in designing future randomized controlled trials in Japan and abroad.

Who wants to join preventive trials?--Experience from the Estonian Postmenopausal Hormone Therapy Trial [ISRCTN35338757]

Background

The interest of patients in participating in randomized clinical trials involving treatments has been widely studied, but there has been much less research on interest in preventive trials. The objective of this study was to find out how many women would be interested in a trial involving postmenopausal hormone therapy (PHT) and how the women's background characteristics and opinions correlated to their interest.

Methods

The data come from recruitment questionnaires (n = 2000) sent to women in Estonia in 1998. A random sample of women aged 45 to 64 was drawn from the Population Registry. The trial is a two-group randomized trial comparing estrogen-progestogen therapy with placebo or no drugs. A brief description of the study was attached to the questionnaires. Women were not told at this stage of the recruitment which group they would be assigned to, however, they were told of the chance to receive either hormone, placebo or no treatment.

Results

After two reminders, 1312 women (66%) responded. Eleven percent of the women approached (17% of the respondents) were interested in joining the trial, and 8% wanted more information before deciding. When the 225 women who stated clearly that they were interested in joining and the 553 women who said they were not interested were compared, it was found that interested women were younger and, adjusting for age, that more had given birth; in other respects, the sociodemographic characteristics and health habits of the interested women were similar to those of the non-interested women. The interested women had made more use of more health services, calcium preparations and PHT, they were more often overweight, and more had chronic diseases and reported symptoms. Interested women's opinions on the menopause were more negative, and they favoured PHT more than the non-interested women.

Conclusion

Unlike the situation described in previous reports on preventive trials, in this case Estonian women interested in participating in a PHT trial were not healthier than other women. This suggests that trials involving PHT are more similar to treatment trials than to preventive trials. In a randomized controlled trial, more information should be obtained from those women who decline to participate.

Patient preferences in randomised controlled trials: conceptual framework and implications for research

Patient preferences have recently been highlighted as a potential threat to the validity of randomised controlled trials (RCTs). Although there have been significant methodological and statistical developments in relation to these issues, comparatively little attention has been paid to the development of a conceptual model concerning preferences and their effects on decision-making. This article describes the development of such a model, which was undertaken in parallel with a systematic review of the empirical data concerning preference effects. The model describes the concept of preference in terms of theoretical concepts from the psychological and economics literature, and describes a preliminary model of the development and operation of preferences in the context of RCTs. The paper then examines the implications of the model for informed consent and recruitment procedures. Key issues for future research are also outlined.

Recruitment of patients into an internet-based clinical trials database: the experience of OncoLink and the National Colorectal Cancer Research Alliance

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.

Barriers to a trial of atherosclerosis prevention in systemic lupus erythematosus

OBJECTIVE

The effectiveness of aggressive management of traditional risk factors for accelerated atherosclerosis in systemic lupus erythematosus (SLE) has been advocated but not proven. We conducted a pilot, randomized, controlled trial of known prevention medications (pravastatin, ramipril, aspirin, and a combination B vitamin) plus individualized cardiovascular prevention education. We describe our experience in recruiting and retaining patients with SLE in this trial.

METHODS

Patients with SLE by American College of Rheumatology criteria who lived within 1 hour of the hospital and had visits within the past 3 years were screened. All eligible patients were contacted by the principal investigator who was not their physician. The reasons for nonparticipation were elicited in a nonjudgmental manner.

RESULTS

A total of 662 patients met the selection criteria for the study. Of these, 295 patients (45%) with contraindications to study medications were excluded. Ninety-seven (40%) of 244 eligible patients refused to participate. More than 40% of those phoned were unwilling to participate and, among those, 19% felt they were too sick, too well, or taking too many medications already. A total of 41 patients were enrolled in the trial, and 22 dropped out within 4 months.

CONCLUSION

SLE is a chronic disease, and the development and testing of interventions aimed at the prevention of long-term sequelae are of paramount importance. Prevention trials in SLE face serious challenges, including the recruitment and retention of participants. Our experience provides insights into the barriers to participation in randomized prevention trials in SLE.

When free condoms and spermicide are not enough: barriers and solutions to participant recruitment to community-based trials

While randomised controlled trials remain the accepted 'gold standard' in medical research, participant recruitment is often problematic, particularly with primary care trials or those requiring healthy volunteers. Such difficulties can jeopardise the trial, leading to early abandonment, reduced statistical power or timetable and budget overruns. Substantial changes in recruitment plans may reduce the generalisability of the research. In order to overcome some of the more common recruitment difficulties, it is important that researchers share their recruitment strategy successes and failures. We report our experience of recruiting healthy volunteers to a condom trial, based within primary care and community populations. This was an RCT of the effect that using an additional spermicidal lubricant has on condom failure. We originally aimed to recruit entirely from Family Planning Clinics, but eventually required a wide variety of strategies. Targeted mailings, newspaper coverage and electronic 'posters' were among the most successful we used to bolster clinic recruitment. Concerned at our slow recruitment rates, we conducted a questionnaire survey investigating the reasons for participation and non-participation in the research completed by 101 trial participants, 112 decliners and 90 controls (total 303). The most important reasons given for taking part included 'considering the research to be important' (85%), 'wanting to help the researchers' (70%), 'having time to help' (62%) and 'getting free condoms and lubricant' (56%). The most popular reasons for declining were 'not wanting to use condoms' (38%), 'partner's unwillingness to take part' (29%), 'not wanting to alter usual contraceptive practice' (27%), 'not having time' (21%). Contrary to expectations, embarrassment and fears about confidentiality were relatively unimportant factors in this decision. In conclusion, the key to attaining recruitment targets was the core research team taking an active part, working closely with clinic staff and maintaining tight control of the process. Altruism remains a powerful motivation for participants, supported by incentives and procedural details to minimise personal inconvenience. Even for intimate research topics, these general factors outweigh specific issues.

Telephone reminders are effective in recruiting nonresponding patients to randomized controlled trials

OBJECTIVE

Studies investigating means of recruiting participants to randomized controlled trials (RCTs) are sparse. We investigated the effects of telephone reminders as a recruitment strategy.

STUDY DESIGN AND SETTING

Sick-listed employees received a written invitation to participate in a study comparing standard treatments with a solution-focused follow-up and were randomly allocated to an intervention or control group (n=703). Those who did not respond within 2 weeks received either 'no reminder' (n=242) or 'attempted telephone reminder' (n=256). Outcome was enrollment to the RCT.

RESULTS

An intention to recruit analysis revealed no significant differences between the groups (P=.229). An intention to phone analysis among nonresponders revealed significant differences between 'no reminder' (recruited 4.5%) and 'attempted telephone reminder' (recruited 12.1%) (P=.003, odds ratio 2.89, 95% confidence interval [CI] 1.42-5.90). An analysis of numbers needed to phone showed that to recruit one more person in this group of nonresponders, we needed to phone 13 persons (95% CI=8-33).

CONCLUSION

Systematic use of telephone calls can increase the recruitment rate among nonresponders in RCTs.

Physicians' reasons for not entering their patients in a randomized controlled trial in Japan

Physicians' not entering their patients can jeopardize the success of a randomized controlled trial (RCT). We used a survey to investigate the possible reasons why physicians who initially agreed to collaborate did not recruit any patients for an RCT being conducted in Japan. A total of 167 questionnaires were sent out and 122 responses were received. Main reasons for not entering patients were: concern about the detrimental effects on the doctor-patient relationship (51.8%), patients' refusal (47.5%), complicated registration and follow-up procedures (34.9%), and not feeling comfortable recruiting their own patients (32.4%). Multivariate logistic regression made it clear that physicians who thought that registering their own patients would damage the doctor-patient relationship and who expected the RCT would fail were more likely to be uncomfortable entering their own patients. Moreover, physicians aged 50 years or older, who felt uncomfortable recruiting their own patients, and saw no advantage in participating in the trial, were more likely to view the enrolment and follow-up procedures as cumbersome. We conclude that training and a manual for obtaining informed consent and a face-to-face demonstration of patient registration/follow-up procedures for the potential participants are prerequisites for increasing physician participation in RCTs in Japan.

Blinding decreased recruitment in a prevention trial of postmenopausal hormone therapy

PURPOSE

To compare the effect of blind design (active drug and placebo) and nonblind design (active drug and no treatment) on recruitment.

SETTING

A primary prevention trial with postmenopausal hormone therapy in Estonia.

METHODS

Women who were eligible and willing to participate on the basis of the questionnaire survey were randomized into blind and nonblind groups. Recruitment rates are based on record keeping, and reasons for participating were requested in the first-year follow-up.

RESULTS

The recruitment was 30% higher in the nonblind group: of the 4,295 women invited, 37% (95% confidence interval CI=35-39%) in the blind group and 48% (95% CI=46-49%) in the nonblind group were recruited. In both groups, once randomized, most of the losses were women who did not attend the first clinical examination: 49% (blind; 95% CI=47-51%) and 40% (nonblind; 95% CI=38-42%). The rest were found ineligible or lost their interest during clinical examinations. The reasons for joining the trial were relatively similar in the two groups.

CONCLUSIONS

Blinding decreased women's interest in joining a long-term preventive trial. Women's reasons for joining the trial were not influenced by blinding.

Medical versus surgical abortion efficacy, complications and leave of absence compared in a partly randomized study

To provide optimal information to women choosing between early medical and surgical abortion, rigorous comparisons of the two methods are warranted. We compared the outcome of 1135 consecutive women with gestational age (GA) < or = 63 days receiving either a medical (600 mg mifepristone and 1 mg gemeprost) or a surgical abortion (vacuum aspiration in general anesthesia). One hundred eleven of these women were randomized for abortion method. Surgical interventions and complications leading to readmission within the following 15 weeks were identified through a computer system. Information about antibiotic treatment, leave of absence and number of contacts to the health care system were obtained from mailed questionnaires. The number of complications was identical after the two methods, but surgical abortion was associated with a higher success rate [97.7% (708/725) vs. 94.1% (386/410), p < .01] and also with a higher risk of antibiotic treatment than medical abortion [7.8% (37/467) vs. 3.7% (13/356), p < .05]. The median leave of absence was shorter in women choosing a medical (1 day) than a surgical termination (2 days), p < .05. On average, one third of all the women requested at least one extra unscheduled consultation apart from a routine follow-up visit. We conclude that the chance of a primary successful termination at GA < or = 63 days is higher after a surgical abortion in general anesthesia compared to a medical abortion induced with 600 mg mifepristone and 1 mg gemeprost. A surgical abortion is associated with an increased risk of antibiotic treatment compared to medical abortion. The women's need for follow-up might be higher than we expect.

Why Cancer Patients Enter Randomized Clinical Trials: Exploring the Factors That Influence Their Decision

Purpose

Few interventions have been designed and tested to improve recruitment to clinical trials in oncology. The multiple factors influencing patients' decisions have made the prioritization of specific interventions challenging. The present study was undertaken to identify the independent predictors of a cancer patient's decision to enter a randomized clinical trial.

Methods

A list of factors from the medical literature was augmented with a series of focus groups involving cancer patients, physicians, and clinical research associates (CRAs). A series of questionnaires was developed with items based on these factors and were administered concurrently to 189 cancer patients, their physicians, and CRAs following the patient's decision regarding trial entry. Forward logistic regression modeling was performed using the items significantly correlated (by univariate analysis) with the decision to enter a clinical trial.

Results

A number of items were significantly correlated with the patient's decision. In the multivariate logistic regression model, the patient's perception of personal benefit was the most important, with an odds ratio (OR) of 3.08 (P < .05). CRA-related items involving supportive aspects of the decision-making process were also important. These included whether the CRA helped with the decision (OR = 1.71; P < .05), and whether the decision was hard for the patient to make (OR = 0.52; P < .05).

Conclusion

Strategies that better address the potential benefits of trial entry may result in improved accrual. Interventions or aids that focus on the supportive aspects of the decision-making process while respecting the need for information and patient autonomy may also lead to meaningful improvements in accrual.

Why ethnic minority groups are under-represented in clinical trials: a review of the literature

Randomised controlled trials (RCTs) are considered to be the gold standard in evaluating medical interventions; however, people from ethnic minorities are frequently under-represented in such studies. The present paper addresses a previously neglected debate about the tensions which inform clinical trial participation amongst people from ethnic minorities, in particular, South Asians, the largest ethnic minority group in the UK. In a narrative review of the available literature, based mainly on US studies, the present authors aim to make sense of the issues around under-representation by providing a theoretical reconciliation. In addition, they identify a number of potential barriers to ethnic minority participation in clinical trials. In so doing, the authors recognise that the recent history of eugenic racism, and more general views on clinical trials as a form of experimentation, means that clinical trial participation among people from ethnic minorities becomes more problematic. Lack of participation and the importance of representational sampling are also considered, and the authors argue that health professionals need to be better informed about the issues. The paper concludes by offering a number of strategies for improving ethnic minority accrual rates in clinical trials, together with priorities for future research.

AACAP 2001 research forum: challenges and recommendations regarding recruitment and retention of participants in research investigations

OBJECTIVE

Clinical research depends on the participation of representative samples. At the 2001 Annual Meeting of the American Academy of Child and Adolescent Psychiatry, the Workgroup on Research conducted a research forum with the purpose of improving recruitment and retention of children and adolescents in research protocols.

METHOD

An interdisciplinary group of participants focused on (1) consumers and families, (2) communities, (3) professionals and health care delivery systems, (4) regulatory bodies, and (5) alternative research designs. Obstacles and challenges were identified and solutions were discussed.

RESULTS

Key recommendations include the following: Investigators must become involved with community stakeholders and more explicitly communicate with families about research procedures, risks, and benefits; budgets should include explicit items for case management and referrals to families who do not meet entry criteria; the culture of clinical settings must incorporate research conducted by clinicians; regulatory bodies must streamline and coordinate protocols and procedures; designs emphasizing flexible treatment strategies and adaptive treatments should be encouraged; and health care systems should consider changing incentives for research participation, including the radical notion that reimbursement be made in terms of improvement rather than service units.

CONCLUSIONS

An integrated approach is recommended, requiring direct involvement of investigators in communities where research is to be conducted.

Demographic differences between consenters and non-consenters in an obstetric anesthesiology clinical study

Willingness to participate in obstetric anesthesiology clinical studies may be influenced by age, parity or ethnicity. This study was designed to determine whether there were demographic differences between consenters and non-consenters in a minimum local analgesic concentration clinical study. Four hundred and fifty-two women were approached for the study and the age, ethnicity and parity of patients who consented or declined to participate were collected. Ethnicity was categorized as Asian or Pacific Islander, black, Hispanic, white, or other. Parametric data were analyzed using t-tests and non-parametric data using chi(2) tests. There were no significant differences in the consent rate based on age or parity. Black Americans were more likely to consent than Asian Americans (P<0.001) and as likely to consent as white Americans. There were no statistically significant differences in the consent rate between Caucasian and Asian Americans. More studies are needed to determine the socioeconomic and demographic factors that affect consent rates of labor patients.

The Clinician as Investigator

The rapid development of new drugs, therapies, and devices has created a dramatic increase in the number of trials needed to properly evaluate them. The majority of patients treated today, many of whom could be eligible for participation in these studies, are seen in community hospitals and medical practices that are not affiliated with an academic medical center. Thus, there is a demonstrable need for physicians in private practice to enlist as investigators in these trials. This article is intended to encourage those physicians by describing the need and providing the rationale for their participation. It covers basic requirements for participating in clinical trials and outlines ethical, regulatory, financial, and other logistical issues of importance for the potential investigator and provides an algorithm for selecting a study for participation. Finally, the appendices review basic elements of study design and statistical principles, which may be of interest to a potential investigator.

Women’s Views Regarding Participation in a Proposed Randomized Controlled Trial of Twin Delivery

OBJECTIVE

To determine the views of women regarding participation in a proposed multicentre randomized controlled trial comparing planned vaginal birth to planned Caesarean delivery for twins at 32 or more weeks' gestation, in which the first twin (twin A) is presenting as a vertex.

METHODS

Pregnant women with a known twin gestation were recruited from 2 hospital centres. Written information was provided about the proposed Twin Birth Study, and the women were then requested to complete a questionnaire to determine their views regarding participation in the proposed trial.

RESULTS

Of the 64 women recruited for the study, 31 (48%) indicated they would be willing to consider participating in the proposed trial (95% CI, 37-60%), 14 (22%) were unsure about trial participation (95% CI, 13-33%), and 19 (30%) indicated they would not be willing to participate in the proposed study (95% CI, 20-42%). The most common reason for agreement to participation was altruism (n = 28). Those who responded "not sure" wished to speak with their partner (n = 5) or their doctor (n = 8) before deciding on participation. Of those who indicated they would not participate in the proposed trial, 12 (63%) indicated they preferred to have a vaginal birth, and 7 (37%) preferred to have a Caesarean section.

CONCLUSIONS

Almost half the women in our sample were agreeable to considering their participation in a randomized trial that will compare planned vaginal birth to planned Caesarean section for twins at 32 or more weeks' gestation with twin A presenting as a vertex. Altruism was the most common reason for agreeing to participate, whereas preference for a specific mode of delivery was the most common reason for declining participation.

[Compliance in HIV infected adults. Study of opportunistic infection prophylaxis with cotrimoxazole in Ivory Coast]

BACKGROUND

The compliance to a daily treatment for illimited duration and the factors that influence it have been rarely studied in sub-Saharian Africa.

OBJECTIVE

Describe the compliance to prophylaxis with cotrimoxazole fort (one tablet per day) and its associated factors in patients infected by HIV participating in a clinical trial in Abidjan.

METHOD

The tablets packed in individual blisters were provided every month, and the blisters were recuperated the following month. A global compliance ratio (GCR) was established for each patient (empty blisters at the end of the study/follow-up period during the study) and monthly compliance ratio [MCR] (empty blisters during a visit/time lapse since last visit). For each monthly visit foreseen in the protocol, a respect of the appointment ratio (RAR) was described (visits foreseen in the protocol respected that month/visits foreseen in the protocol). The association of GCR with the characteristics on inclusion was studied using logistic regression methods.

RESULTS

530 adults were followed-up for a mean of 10 months. The MCR and the RAR progressed in parallel, decreasing the first 5 months and stabilizing at around 0.80 for the RAR and 0.70 for the MCR. The mean GCR was of 0.77. Three hundred and nine patients (58%) were considered as compliant (0.80<GCR<1). In multivariate analysis, those belonging to the group of compliers were associated with a paid occupation and with a past of tuberculosis, and was not associated with age, gender, level of education, nationality, civil status, number of persons in the home, proximity of a care center, clinical grade or CD4.

DISCUSSION

The estimated compliance was correct and stable. The association with a history of tuberculosis suggests that a person having already followed prolonged daily treatment would be more readily compliant to other long term treatments.

CONCLUSION

In Africa, cotrimoxazole is initiated long before the stage of antiretroviral treatment. The concern regarding the efficacy of such prophylaxis raises the question of compliance early on in the disease. This prepares the teams that organise the management of such patients to being faced with the problems of compliance to antiretrovirals.

Design and analysis of pilot studies: recommendations for good practice

Pilot studies play an important role in health research, but they can be misused, mistreated and misrepresented. In this paper we focus on pilot studies that are used specifically to plan a randomized controlled trial (RCT). Citing examples from the literature, we provide a methodological framework in which to work, and discuss reasons why a pilot study might be undertaken. A well-conducted pilot study, giving a clear list of aims and objectives within a formal framework will encourage methodological rigour, ensure that the work is scientifically valid and publishable, and will lead to higher quality RCTs. It will also safeguard against pilot studies being conducted simply because of small numbers of available patients.

Web-based decision support for clinical trial eligibility determination in an international clinical trials network

Matching individuals to multisite cooperative clinical trials can be a complex and nonintuitive decision process that expends considerable time and may be prone to errors. We developed and tested a web-based decision support tool to aid investigators in matching patients to open clinical trials for children with rhabdomyosarcoma in the context of an international cooperative cancer clinical trials network. A decision tree for trial eligibility based on eight clinical variables representing major disease characteristics was translated into a web-based format. In a blinded fashion, we assessed the accuracy of the tool in assigning 100 randomly selected cases to the proper clinical trial. The web-based tool assigned patients to the proper clinical trial in all 100 randomly selected cases. The time needed to enter data and receive results using this tool is about 1 minute per patient entered. It is feasible to develop a web-based tool to help investigators in matching patients to clinical trials. When such decisions are complex and nonintuitive, such tools have the potential to improve the accuracy of clinical trial assignment and save time.

Patient recruitment to a randomized clinical trial of behavioral therapy for chronic heart failure

Background

Patient recruitment is one of the most difficult aspects of clinical trials, especially for research involving elderly subjects. In this paper, we describe our experience with patient recruitment for the behavioral intervention randomized trial, "The relaxation response intervention for chronic heart failure (RRCHF)." Particularly, we identify factors that, according to patient reports, motivated study participation.

Methods

The RRCHF was a three-armed, randomized controlled trial designed to evaluate the efficacy and cost of a 15-week relaxation response intervention on veterans with chronic heart failure. Patients from the Veterans Affairs (VA) Boston Healthcare System in the United States were recruited in the clinic and by telephone. Patients' reasons for rejecting the study participation were recorded during the screening. A qualitative sub-study in the trial consisted of telephone interviews of participating patients about their experiences in the study. The qualitative study included the first 57 patients who completed the intervention and/or the first follow-up outcome measures. Factors that distinguished patients who consented from those who refused study participation were identified using a t-test or a chi-square test. The reason for study participation was abstracted from the qualitative interview.

Results

We successfully consented 134 patients, slightly more than our target number, in 27 months. Ninety-five of the consented patients enrolled in the study. The enrollment rate among the patients approached was 18% through clinic and 6% through telephone recruitment. The most commonly cited reason for declining study participation given by patients recruited in the clinic was 'Lives Too Far Away'; for patients recruited by telephone it was 'Not Interested in the Study'. One factor that significantly distinguished patients who consented from patients who declined was the distance between their residence and the study site (t-test: p < .001). The most frequently reported reason for study participation was some benefit to the patient him/herself. Other reasons included helping others, being grateful to the VA, positive comments by trusted professionals, certain characteristics of the recruiter, and monetary compensation.

Conclusions

The enrollment rate was low primarily because of travel considerations, but we were able to identify and highlight valuable information for planning recruitment for future similar studies.

The Gini coefficient as a measure for understanding accrual inequalities in multicenter clinical studies

OBJECTIVE

Clinical sites participating in multicenter trials may have unequal performance in recruiting subjects. We propose using the Gini coefficient as a quantitative measure of site accrual inequalities.

STUDY DESIGN AND SETTING

We evaluated the relationship of this metric to other study characteristics across 166 clinical studies (27,865 subjects) conducted by the AIDS Clinical Trials Group between 1986 and 1999.

RESULTS

Overall there was a modest recruitment inequality among clinical centers (mean Gini=0.33). In multivariate modeling, site accrual inequalities were higher when there was more protracted enrollment, and a larger number of sites and were lower in antiretroviral studies than other studies. In long-term studies, the site accrual inequality increased significantly over time (P=0.004). In efficacy trials, a higher Gini coefficient was associated with higher likelihood of the study results being statistically significant (P=0.010).

CONCLUSION

The Gini coefficient may be easily and routinely incorporated in the description of the characteristics of a clinical study and may provide insights about its enrollment pattern.

Willingness of dialysis patients to participate in a randomized controlled trial of daily dialysis

BACKGROUND

The National Institutes of Health (NIH) has proposed conducting randomized controlled trials comparing short, daily, in-center hemodialysis with conventional hemodialysis. However, there is concern that difficulties recruiting patients may prevent the successful completion of such trials if patients believe the inconveniences of daily dialysis outweigh any potential health benefits.

METHODS

To gauge willingness to participate in a daily dialysis trial, we described a hypothetical, randomized controlled trial comparing conventional to daily hemodialysis to 209 chronic hemodialysis patients, and assessed their motivations for and concerns about participating.

RESULTS

We found that 85 patients (41%) of 209 patients who agreed to be interviewed expressed some willingness to participate in the hypothetical trial. Patients who expressed greater willingness to participate were younger (OR for participating = 0.96 per year, 95% CI = 0.94 to 0.98, P= 0.001), less likely to smoke (OR = 0.38, 95% CI = 0.17 to 0.84, P= 0.017), more likely to have been hospitalized during the last 12 months (OR = 2.8, 95% CI = 1.5 to 5.5, P= 0.002), less likely to have reactive airway disease (OR = 0.21, 95% CI = 0.06 to 0.69, P= 0.01) or coronary artery disease (OR = 0.20, 95% CI = 0.08 to 0.53, P= 0.001), and less likely to be on the waiting list for a kidney transplant (OR = 0.23, 95% CI = 0.10 to 0.50, P < 0.0001).

CONCLUSION

The study suggests that less than half of eligible patients would be willing to participate in the randomized controlled trial. Differing willingness to participate across patient subgroups suggests that certain subgroups (i.e., older patients and those with coronary artery disease) will need to be targeted to ensure that results are generalizable to most hemodialysis patients.

The trials and tribulations of intrapartum studies

OBJECTIVE

To review the reporting of randomised controlled trials for intrapartum interventions.

METHODS

This was a literature search addressing the period from the publication of the CONSORT statement i.e. 1996-2002. Databases searched: Medline and CINAHL. Search terms: pregnancy, low-risk, normal, intrapartum, labour and labor.

INCLUSION CRITERIA

randomised controlled trials reported in English which involved women experiencing: normal or 'low risk' pregnancy; intrapartum interventions; women who had a spontaneous onset of labour.

DATA EXTRACTION

timing of consent and randomisation, proportion of eligible women recruited, 'losses' to the study. Included Studies fourteen published and one unpublished study that fitted the inclusion criteria were identified. Three studies were subsequently excluded because of a lack of information about the method and a further study was excluded due to its small sample size.

FINDINGS

Three strategies for recruitment and randomisation for intrapartum studies were reported in the literature: antenatal recruitment and randomisation; consent and randomisation conducted on admission in labour or at the time of the intervention; staged recruitment and randomisation, which may be two- or three-staged. Different study designs have done much to improve the appearance of intrapartum studies and reduce post-randomisation losses. However, the problem of bias in RCTs is not limited to attrition alone and these designs may simply be moving the problem to an earlier stage in the study resulting in selection bias and limiting generalisability.

CONCLUSIONS

The importance of accurate documentation of numbers at all stages in the research process is highlighted, in particular the number of eligible people not recruited, to allow the reader to assess the generalisability of the study.

Clinical Trials in Neurology

This chapter provides extensive coverage of concepts related to controlled clinical trials in neurology. It describes the main issues in clinical trial design, conduct, and analysis, by examples from neurological research. It begins with a summary of the objectives of Phase I through Phase IV trials, followed by a discussion of the commonly used study designs for clinical trials (parallel group design, factorial design, crossover design, N-of-one design). It then describes important principles for the conduct of clinical trials, including methods for recruitment and retention of clinical trial subjects, approaches to minimizing bias due to unblinding, and techniques for monitoring compliance and adverse events. It discusses methods of randomization and choice of primary and secondary measures of treatment outcome and summarizes statistical approaches to clinical trial data, including intent-to-treat analyses, explanatory analyses, per protocol analyses, and on-treatment analyses. Methods for subgroup analyses and planning of interim analyses are also discussed. One section of the chapter is devoted to ethics of controlled clinical trials.

Hypertensive patients' willingness to participate in placebo-controlled trials: implications for recruitment efficiency

BACKGROUND

Underenrollment and selective enrollment plague many clinical trials. Little is known about why hypertensive patients agree or refuse to participate in placebo-controlled trials (PCT) of antihypertensive drugs, whether the prospect of receiving placebo influences willingness to participate (WTP), or whether patients who participate differ from those who do not.

METHODS

We described a hypothetical PCT of a new antihypertensive drug to 126 patients who would be eligible for ongoing phase III trials. We solicited patient motivations and concerns regarding trial participation by using open-ended questions, assessed the patients' stated WTP, and used logistic regression to determine patient characteristics associated with WTP. We reassessed WTP in 62 patients after revealing, in random order, that 10%, 30%, and 50% of patients would receive placebo.

RESULTS

The most commonly cited motivations for participating included personal health benefits (40%), helping other patients (37%), and contributing to scientific knowledge (15%). The most common concerns were having to stop current medications (56%), inconvenience/annoyance (38%), fear of known side effects (35%), and the possibility of receiving placebo (24%). Overall, 47% of patients (95% confidence interval, 38% to 56%) were willing to participate. Younger patients (57% versus 37%; P =.01), nonsmokers (50% versus 24%; P =.04), and patients who had participated in research previously (77% versus 20%; P =.009) were all significantly more willing to participate. Fewer patients were willing to participate as the percentage who would receive placebo increased (P =.02), but randomly assigning fully half of patients to placebo still yielded maximal recruitment efficiency.

CONCLUSIONS

Hypertensive patients participate in trials for altruistic and personal health reasons. Differences between patients who do or do not participate may influence trial outcomes. The proportion of patients receiving placebo influences some patients' enrollment decisions but is not a key determinant of recruitment efficiency.

Evaluación de los proyectos de investigación clínica en un centro monográfico de cáncer

BACKGROUND AND OBJECTIVE

The number of clinical trials in cancer patients has experienced an important growth during last years. However, it is difficult to find data showing this activity in Spanish Hospitals. This study analyses the clinical trials data bases between 1996 and 2002 in a cancer center.

MATERIAL AND METHODS

We perform a descriptive analysis of data from: selection of protocols, origin of proposals, sponsors, investigators, studies performed and published; demographic data about patients and phase of the studies in which they have been included.

RESULTS

Evaluation was undertaken with a standardised protocol review assessment. 337 proposals of clinical trials were evaluated during 1996-2002, with a decreasing acceptance index (62.5% to 39.18%, respectively), the number of proposals has grown from 16 in 1996 to 74 in 2002. The general recruitment index was 6.64%. Between 1995-2002, 1479 patients were registered; only 5% were older than 75 years. Pharmaceutical Companies sponsored the majority of the studies, although Co-operative Groups promote an important number of studies, especially in Haematology and Radiotherapy. Thirteen studies performed between 1996-1998 had been published, and 3 more are accepted for publication (69.5%).

CONCLUSIONS

The number of patients included in clinical trials is limited and older patients are not well represented in them.

Who can best recruit to randomized trials? Randomized trial comparing surgeons and nurses recruiting patients to a trial of treatments for localized prostate cancer (the ProtecT study)

BACKGROUND AND OBJECTIVE

Recruitment to randomized trials is often difficult, but few studies have investigated interventions to improve recruitment. In a randomized trial nested within a trial of treatments for localized prostate cancer, we investigated the comparative effectiveness and cost-effectiveness of nurses and surgeons in recruiting patients.

METHODS

Men with localized prostate cancer were randomized to see a nurse or urologic surgeon for an "information appointment" in which they were asked to consent to the ProtecT treatment trial comparing surgery, radiotherapy, and active monitoring. Analysis was conducted by intention to treat using chi-square with 95% confidence intervals for proportions and differences between groups. An economic evaluation was performed using the duration of appointments and grade of recruitment staff.

RESULTS

Case-finding identified 167 men with localized prostate cancer. One hundred fifty (90%) took part in the recruitment trial. There was a 4.0% difference between nurses and surgeons in recruitment rates (67% nurses, 71% urologists, 95% CI -10.8% to +18.8%, P=.60). Cost-minimization analysis showed that nurses spent longer times with patients but surgeon costs were higher and nurses often supported surgeon-led clinics.

CONCLUSION

Nurses were as effective and more cost-effective recruiters than urologic surgeons. This suggests an increased role for nurses in recruiting patients to randomized trials.

Patient entry into randomized controlled trials of colorectal cancer treatment: factors influencing participation

BACKGROUND

The objective of this study was to investigate willingness to participate in hypothetical surgical randomized controlled trials (RCTs) among patients and clinicians, who answered as if they themselves were patients.

METHODS

We interviewed consecutive patients with colorectal cancer admitted for surgery at a tertiary center in Sydney, Australia. We mailed a questionnaire to all colorectal surgeons and medical oncologists in Australia.

RESULTS

Overall, 42% (95% CI, 32% to 52%) of patients, 44% (95% CI, 29% to 60%) of surgeons, and 63% (95% CI, 53% to 72%) of oncologists were willing to enter a randomized clinical trial. Oncologists were significantly more likely to participate than either surgeons (P <.001) or patients (P =.001). No significant associations were seen between willingness to participate and patient characteristics. "Risk of cancer recurrence" was rated by the most patients and doctors as an important reason for refusal of trial entry, although patients additionally identified dislike of randomization and quality of life concerns as important barriers.

CONCLUSION

More than 40% of patients were willing to enter into a hypothetical RCT involving surgery. Aversion to randomization and perceptions of differential impact of treatment on cancer recurrence and quality of life are likely to be major barriers to patient accrual in trials of colorectal cancer treatment.

Perceptions of equipoise are crucial to trial participation: a qualitative study of men in the ProtecT study

Recruitment to trials is known to be difficult. Previous research suggests that a crucial factor may be participants' difficulty with the concept of randomization. This study explored patients' perceptions of randomization and reasons for consent or refusal to participate in the ProtecT study (a randomized trial of surgery, radiotherapy, and monitoring for localized prostate cancer). In-depth interviews were conducted with 21 men diagnosed with localized prostate cancer who were invited to participate in the ProtecT treatment trial. Interviewees were selected purposefully from three U.K. clinical centers to ensure the inclusion of similar proportions of those agreeing or refusing random treatment allocation in each of the treatment groups. Interviews explored men's recall and understanding of chance, comparison, and equipoise, and reasons for consent/refusal of randomization and acceptance/rejection of treatment allocation. Data were analyzed methodically using the techniques of constant comparison. Checking of coding and interpretation was assured by four experienced qualitative researchers. Recall and understanding of the major principles of the randomized design were good and were similar for "chance" and "comparison" between those who consented to and refused randomization. Clinical equipoise, however, caused difficulty. Almost all recalled and understood it, but those who found it acceptable tended to consent to randomization and those who could not accept it tended to refuse to participate. Belief in clinical equipoise was key to participants' consent to randomization. Ensuring patients understand and accept equipoise may thus increase their readiness to consent to participate in trials. A priority for future research is to focus on the provision and presentation of suitable and effective trial information, concentrating in particular on the neglected concept of clinical equipoise.