Recruitment for controlled clinical trials: Literature summary and annotated bibliography

Controlled Clinical Trials

Volumn 18, Issue 4, 1997, Pages 328-352

  Lovato, Laura C ^a   Hill, Kristin ^a   Hertert, Stephanie ^d   Hunninghake, Donald B ^b   Probstfield, Jeffrey L ^a,c  

^a Fred Hutchinson Cancer Research Center   (United States)

^b UNIVERSITY OF MINNESOTA   (United States)

^c UNIVERSITY OF WASHINGTON   (United States)

^d NONE

Author keywords

Clinical trials; Patient participation; Recruitment; Study design

Indexed keywords

ACQUIRED IMMUNE DEFICIENCY SYNDROME; ARTICLE; CLINICAL PROTOCOL; CLINICAL TRIAL; CONFIDENTIALITY; CONTROLLED CLINICAL TRIAL; CONTROLLED STUDY; COST; CULTURAL FACTOR; HUMAN; HUMAN IMMUNODEFICIENCY VIRUS INFECTION; LANGUAGE; MEDICAL INFORMATION; MEDICAL LITERATURE; MEDICAL RESEARCH; METHODOLOGY; OCCUPATION; PATIENT; PATIENT ATTITUDE; PHYSICIAN ATTITUDE; PRIMARY PREVENTION; PUBLICATION; REGISTRATION; SCREENING;

CLINICAL TRIALS; HUMANS; PATIENT SELECTION;

EID: 0030747503     PISSN: 01972456     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0197-2456(96)00236-X     Document Type: Article

References (98)

1. Hunninghake DB, Darby CA, Probstfield JL. Controlled Clin Trials 1987;8:6S-30S.
2. Friedman LM, Furberg CD, DeMets DL. Fundamentals of Clinical Trials 3rd ed. St. Louis: Mosby-Yearbook, Inc.; 1996.
3. Wittes J. Subgroup representation in randomized clinical trials. In: Clinical Trials and Statistics: Proceedings of a Symposium, Board on Mathematical Sciences, National Research Council. National Academy Press; 1993:15-22.
4. National Institutes of Health. NIH guidelines on the inclusion of women and minorities as subjects in clinical research. Federal Register, 1994;59:14508-14513.
5. National Institutes of Health. Outreach Notebook for the NIH Guidelines on Inclusion of Women and Minorities as Subjects in Clinical Research. Bethesda, MD: National Institutes of Health, 1994.
6. National Institutes of Health. Health Behavior Research in Minority Populations: Access, Design, and Implementation. Co-Sponsored by the National Heart, Lung, and Blood Institute and The Johns Hopkins Medical Institutions. U.S. Department of Health and Human Services, Public Health Service, National Institutes of Health. NIH Publication No. 92-2965, 1992.
7. Hertert S, Bailey G, Cottinghan V, Carmody S, Egan D, Johnson P, Probstfield J. Community volunteers as recruitment staff in a clinical trial: the systolic hypertension in the elderly program (SHEP) experience. Controlled Clin Trials 1996;17:23-32.
8. Agras WS, Bradford RH. Recruitment: An introduction. Circulation 1982;66:IV2-IV5. An overview of the recruitment process is presented, including a definition of relevant terms, a summary of the complex problems that researchers have encountered in reaching specific recruitment goals, and suggestions for planning and implementing effective recruitment campaigns. The paper presents the results of the Coronary Primary Prevention Trial, which involved a mass screening of almost one-half million potential participants.
9. Agras WS, Bradford RH, Hunninghake DB, Knoke J, Marshall GD, McKeown M. Participant recruitment to the coronary primary prevention trial. J Chronic Dis 1983;36:451-465. This report describes the recruitment experience of the Coronary Primary Prevention Trial, including results from each major recruitment source and trial center. Recommendations for planning future clinical trials include conducting a pilot recruitment campaign, selecting more centers than the minimum required for optimum accrual, and following and monitoring each center's progress.
10. Agras WS, Marshall GD. Recruitment for the coronary primary prevention trial. Clin Pharmacol Ther 1979;25:688-690. A preliminary account of the recruitment process used in the Coronary Primary Prevention Trial is given. The extension of sources to include community screenings resulted in a more rapid acquisition of contacts than through physician and laboratory referrals. The workload and complexity of the recruitment effort led to the creation of the job of recruitment coordinator in each of the clinics. Potential delays in reaching maximal recruitment rates point to the need for detailed planning before beginning a large-scale recruitment campaign.
11. Agras WS, Marshall GD, Kraemer HC. Planning recruitment. Circulation 1982; 66:IV54-IV58. The results from the Coronary Primary Prevention Trial have served as the basis for developing a comprehensive model for planning recruitment campaigns. A major component of the model is its quantitative approach to the selection of recruitment strategies to accomplish goals within a prescribed period. Recommendations for recruitment include advance planning, delineations, broad outlines and detailed local plans, a data-based system for each local and national effort, alternative strategies, and further research.
12. Atkins CJ, Patterson TL, Roppe BE, Kaplan RM, Sallis JF, Nadar PR. Recruitment issues, health habits, and the decision to participate in a health promotion program. Am J Prev Med 1987;3:87-94. This article describes recruitment methods and the representativeness of participants in the San Diego Family Health Project, a study to evaluate the effectiveness of a family-based behavior-change intervention in Anglo and Mexican-American families. Successful recruitment requires sufficient time to establish community awareness and make personal contacts, and sufficient flexibility among recruitment locations.
13. Baines CJ. Impediments to recruitment in the Canadian national breast screening study: response and resolution. Controlled Clin Trials 1984;5:129-140. An analysis is provided of the severe recruitment problems that jeopardized the Canadian National Breast Screening Study. The difficulties the multicenter randomized trial experienced in accruing an adequate number of participants are described, as well as the solutions that resolved the problems. The data on response rates, cost, and women's attitudes toward the study are provided.
14. Benson AB, Pregler JP, Bean JA, Rademaker AW, Eshler B, Anderson K. Oncologists' reluctance to accrue patients onto clinical trials: an Illinois cancer center study. J Clin Oncol 1991;9:2067-2075. (Comment in J Clin Oncol 1991;9:1927-1930. Comment in J Clin Oncol 1992;10:672-673.) A survey of physician members of the Illinois Cancer Center was conducted to determine factors that presented a significant barrier to entering patients into clinical trials. Factors examined were the impact of trials on patients and physicians, excessive time commitment, intrusion on the patient/physician relationship, issues related to informed consent, financial burden, and trial-protocol design.
15. Bjornson-Benson WM, Stibolt TB, Manske KA, Savela KJ, Youtsey DJ, Buist AS. Monitoring recruitment effectiveness and cost in clinical trial. Controlled Clin Trials 1993;14:52S-67S. Rapid feedback for each recruitment method using a monitoring system is emphasized to analyze cost and adjust focus to successful strategies. Five recruitment strategies used in this Lung Health Study site included media (TV, radio, newspapers), neighborhood promotion, direct mail, worksite promotion, and referral by other study participants. Cost comparisons and effectiveness of each strategy are presented.
16. Borhani NO, Tonascia J, Schlundt DG, Prineas RJ, Jefferys JL for the Hypertension Prevention Trial Research Group. Recruitment in the hypertension prevention trial. Controlled Clin Trials 1989;10:30S-39S. This paper reports the process of recruiting participants for the HPT trial, methods used to identify and contact potential study participants, and the cost of recruitment. The study succeeded in achieving its stated recruitment goals in the planned time frame. Initial contact was done primarily through targeted direct mailings with personalized letters, resulting in a high rate of persons randomized to persons screened. A cost analysis showed that failed appointments alone accounted for nearly 10% of the total costs related to the recruitment effort.
17. Bradford, RH. Participant recruitment to the lipid research clinics coronary primary prevention trial. Controlled Clin Trials 1987;8:31S-40S. This paper presents characteristics of eight recruitment sources and recommendations for those undertaking a similar study. Recruitment sources included referrals from physicians or clinical laboratories, blood banks, clinical studies, community screenings (screening at community events or locations, or involving community organizations), direct mailings, media, and occupational (worksite) screenings. The efficiency of various recruitment strategies varied among recruitment sources and among clinical centers.
18. Brand PLP, Kerstjens HAM, Postma DS, Sterk PJ, Quanjer H, Sluiter HJ, Dijkman JH, van Herwaarden CLA, Hilvering C, Jansen JM, Koeter GH, Kreukniet J. Long-term multicentre trial in chronic nonspecific lung disease: methodology and baseline assessment in adult patients. Eur Respir J 1992;5:21-31. This three-year study was conducted in six university centers to determine if therapeutic intervention directed at airway obstruction and hyperresponsiveness is superior to one directed at airway obstruction alone. All centers found recruitment much more difficult than expected, requiring 16 months of effort, twice as long as expected. More than 50% of those asked to participate refused; a larger proportion of these used inhaled corticosteriods.
19. Buchwald H, Matts JP, Hansen BJ, Long JM, Fitch LL. Program on surgical control of the hyperlipidemias (POSCH): recruitment experience. Controlled Clin Trials 1987;8:94S-104S. Difficulties in recruitment for the POSCH study led to the implementation of a Model Clinic concept. The recruitment effort was directed toward specific communities, with intense effort over a specific period of time and then annual repetition. The process began with letters, phone calls, and then visits by study-clinic staff to area hospitals to get permission to review their MI patient records and establish rapport with the physicians of potential patients. This approach included a saturation effort through the media to inform specific communities about the POSCH study and to encourage community and individual participation.
20. Carew B, Ahn S, Boichot H. Dierenfeldt B, Dolan N, Edens T, Weiner D, Probstfield JL. Recruitment in the studies of left ventricular dysfunction (SOLVD): strategies for screening and enrollment in two concurrent but different trials. Controlled Clin Trials 1992;13:325-338. Recruitment to parallel related but separate studies is described. Emphasis is given to an overall recruitment plan individualized to each clinic and the need for flexibility so that changes in strategies can be implemented in a timely fashion during planned recruitment activities. Differences in recruitment of symptomatic and asymptomatic screenees are noted. Use of laboratory results for identification of potential participants is described. The importance of wide entry criteria and its impact on overall recruitment is demonstrated.
21. Cassileth BR, Lusk EJ, Miller DS, Hurwitz S. Attitudes toward clinical trials among patients and the public. JAMA 1982;248:968-970. Attitudes toward clinical research were assessed through questionnaires completed anonymously by 104 patients with cancer, 84 cardiology patients, and 107 members of the general public. The results indicate that diverse respondents viewed clinical trials as important and ethical and as a means of attaining superior clinical care. Contributions to medical knowledge and to helping future patients were also identified as important.
22. Charlson ME, Horwitz RI. Applying of results of randomized trials to clinical practice: impact of losses before randomization. Br Med J 1984;289:1281-1284. The results of a survey conducted on 41 trials from the National Institutes of Health to determine the magnitude and source of prerandomization losses in clinical trials are presented. The findings indicate that refusal by patients accounted for many fewer nonparticipants in trials than had been previously suggested. To minimize the loss of potential participants, the use of less restrictive criteria for entry is recommended. Screening large numbers of patients seems to be a realistic requirement for achieving recruitment goals.
23. Collins JF, Bingham SF, Weiss DG, Williford WO, Kuhn RM. Some adaptive strategies for inadequate sample acquisition in veterans administration cooperative clinical trials. Controlled Clin Trials 1980;1:227-248. This article considers patient recruitment in seven Veterans Administration cooperative studies and the adaptive strategies used in response to inadequate sample acquisition. These strategies included re-evaluation of the required sample size, the addition of new hospitals, the replacement of poorly recruiting hospitals, the extension of the patient intake period, and the modification of the patient exclusion-inclusion criteria.
24. Connett JE, Bjornson-Benson WM, Daniels K for the Lung Health Study Research Group: Recruitment of Participants in the Lung Health Study, II. Assessment of recruiting strategies. Controlled Clin Trials 1993;14:38S-51S. This paper describes the effectiveness of five general methods in producing participants eligible for the study: worksites, public sites, mail/phone, media, and other. Mail/phone and media were the most effective strategies. Female screenees who passed first-screen eligibility criteria were more likely than males to refuse further participation.
25. Constantine W. Haynes CW, Spiker D, Kendall-Tackett K, Constantine NA. Recruitment and retention in a clinic trial for low birth weight, premature infants. J Dev Behav Pediatr 1993;14:1-7. Successful recruitment was due largely to attention and resources allocated to ensure that all potential participants were approached and that enrollment and retention were high. High recruitment and retention rates were attributed to the intense effort by the national coordinating center to provide detailed training, written protocols and on-site monitoring to help clinical-center staff in their recruitment and retention planning and process.
26. Cotton DJ, Finkelstein DM, He W, Feinberg J for the AIDS Clinical Trials Group. Determinants of accrual of women to a large multicenter clinical trials program of human immunodeficiency virus infection. J Acquir Immune Defic Syndr 1993; 6:1322-1328. Enrollment and demographic data of the AIDS Clinical Trials Group (ACTG) were analyzed to determine factors influencing the enrollment of women in a large multicenter human immunodeficiency virus (HIV) clinical trials program. The enrollment of women was low and appeared to vary by region. Units with female principal or coprincipal investigators had more than twice the percentage of female enrollment as did units headed by men.
27. Cramer JA. Patient recruitment and compliance issues in clinical trials. New Antiepileptic Drug Development: Preclinical and Clinical Aspects (Epilepsy Res. Suppl. 10).: Elsevier Science Publishers B.V.; 1993:211-222. This article focuses on the types of patients most appropriate for antiepileptic drug trials. A variety of strategies can be used to identify patients for potential enrollment. Topics discussed include sources of patients, developing a plan, goals and quotas, inclusion criteria, planning for a new clinical trial, and adherence.
28. DeMets DL, Williams GW, Brown BW Jr, and the NOTT Research Group. A case report of data monitoring experience: the nocturnal oxygen therapy trial. Controlled Clin Trials 1982;3:113-124. This article discusses the issues associated with the monitoring of data in clinical trials, including the multiplicity of outcomes, decisions about the extension of the patient recruitment period to achieve specified sample-size goals, and problems in monitoring patient survival data when a lag occurs in the reporting of events. The results of the study suggest that the data-monitoring group should consider a variety of factors, such as ethical responsibilities to patients, when deliberating about early termination of a trial.
29. Deyo RA, Bass JE, Walsh NE, Schoenfeld LS, Ramamurthy S. Prognostic variability among chronic pain patients: implications for study design, interpretation, and reporting. Arch Phys Med Rehabil 1988; 69:174-178. Fifty-five subjects were recruited through lay publicity for a clinical trial of therapy for chronic back pain. These patients were then compared to 61 routine pain-clinic patients. The conclusions suggest that the site and method of recruitment may influence the generalizability of the results.
30. The Diabetes Control and Complications Trial (DCCT) Research Group. Diabetes control and complications trial (DCCT): results of feasibility study. Diabetes Care 1987;10:1-19. The DCCT was a multicenter, randomized clinical trial involving 21 study sites. A pool of 1037 patients completed the initial visit, and 656 (63%) signed the first informed consent to begin the prerandomization testing. Of this group 278 patients were enrolled.
31. Durkin DA, Kjelsberg MO, Buist AS, Connett JE, Owens GR, and Recruitment Directors of the Lung Health Study for the Lung Health Study Research Group. Recruitment of participants in the lung health study, I: description of methods. Controlled Clin Trials 1993;14:20S-37S. The plans, methods, and experiences of recruitment personnel at each of the participating clinical centers in the Lung Health Study are described. Screening of more than 73,000 male and female smokers aged 35-60 was required to randomize 5887 participants. Worksite, public site, mass mail, telephone, media, and referral strategies were the most frequently used methods. Two of the clinics discussing the particulars of their recruitment programs cite similar response rates to first and second mailings using the same mailing list.
32. Easterbrook PJ. Directory of registries of clinical trials. Stat Med 1992;11:345-423. This article describes the registry as a resource for clinical trial participants. Registries can be used to inform doctors and patients of open slots available in appropriate trials. Most of these registries occur in HIV research.
33. El-Sadr W, Capps L. The challenge of minority recruitment in clinical trials for AIDS. JAMA 1992;267:954-957. This article analyzes some of the factors that affect recruiting and retaining African-American patients in clinical trials research for HIV infection. Obstacles to enrollment begin at the two main mechanisms of enrollment - physician-referral and self-referral. Barriers for the participant include lack of trust in medical research and no previous knowledge of the clinical trial process. In addition, minority patients traditionally have sought care in local clinics and are unwilling or unable to move out of that area of comfort. The social needs of minority populations may be impediments to participation. Solutions are discussed.
34. Engelking C. Facilitating clinical trials. Cancer 1991; 67:1793-1797. This article addresses the provider and patient inhibitors to enrolling cancer patients into clinical trials and the expanded role the nurse can play as a teacher, counselor, supporter, and liaison between the physician, the patient, and the clinical trial sponsor. Nursing involvement can be instrumental in helping cancer patients gain access to clinical trials and can ensure rational decision-making, quality of life, and patient safety.
35. Ford CE, Langford HG, Palmer MJ. Recruitment in the hypertension detection and follow-up program (HDFP). Controlled Clin Trials 1987;8:54S-67S. Strong central leadership was essential in coordinating multiple recruitment sites in the HDFP. Recruitment results suggest that a population-based screening program for a high-prevalence condition such as hypertension is an effective mode of recruitment.
36. Gaston M, Smith J, Gallagher D, Flournoy-Gill Z, West S, Bellevue R, Farber M, Grover R, Koshy M, Ritchey AK, Wilimas J, Verter J, CSSCD Study Group. Recruitment in the cooperative study of sickle cell disease (CSSCD). Controlled Clin Trials 1987;8:131S-140S. Successful recruitment in 27 months of 3200 participants of both sexes and all ages is attributed to the fact that most staff members involved in recruitment were African-American on an active recruitment committee with an involved chairperson, and to the interest and involvement of the clinic director. Many of the clinics had a history of working with active community sickle-cell groups.
37. Gerace TA, George VA, Arango IG. Response rates to six recruitment mailing formats and two messages about a nutrition program for women 50-79 years old. Controlled Clin Trials 1995;16:422-431. This paper reports results of two studies of response rates for recruitment mailings in the Women's Health Trial. The first study showed that more women responded to a short message than to long message. The texts of the messages are included. The second study showed no difference between any combination of handwritten envelopes or machine-printed labels, and formal invitation or business letter with name and address of recipient or business letter without name and address of recipient. A detailed discussion of the variables that may affect whether or not women open, read, and respond to recruitment mailings is given.
38. Goodman GE, Omenn GS, Thornquist MD, Lund B, Metch B, Gylys-Colwell I. The carotene and retinol efficacy trial (CARET) to prevent lung cancer in high-risk populations: pilot study with cigarette smokers. Cancer Epidemiol Biomarkers Prev 1993;2:389-396. The Smokers Pilot Study evaluated recruitment strategies and the potential number of recruitable current and former smokers from target populations. Response, eligibility, and randomization rates from two survey mailings are reported. Insurance company lists were used successfully. The results of this pilot were used in planning for the full-scale CARET study.
39. Gotay CC. Accrual to cancer clinical trials: directions from the research literature. Soc Sci Med 1991; 33:569-577. This paper analyzed the research literature on accrual rates of patients to cancer therapy trials. The main issues identified were physician-related variables, such as difficulty with informed consent, preference of treatment, difficulty in finding appropriate protocols, and patient-related factors, such as strict eligibility criteria, the way the information was presented, age and socioeconomic status, and the perceived benefit.
40. Hall WD. Screening and recruitment of elderly participants into large-scale cardiovascular research trials. Inclusion of Elderly Individuals in Clinical Trials. Cardiovascular Disease and Cardiovascular Therapy As a Model: Marion Merrell Dow Inc.; 1993: 67-87. This article provides examples of the recruitment experiences of 15 cardiovascular studies, including recruitment period, number of clinical centers, mean age range, percent male, percent African-American, number of initial contacts, number of participants recruited, and recruitment months. The time needed to accomplish recruitment exceeded the best estimates of the planning committees by an average of 27%. Five recruitment strategies are discussed: community screenings, medical chart reviews, large-scale mailings, media campaigns, and referrals from community physicians.
41. Harrison K, Vlahov D, Jones K, Charron K, Clements ML. Medical eligibility, comprehension of the consent process, and retention of injection drug users recruited for an HIV vaccine trial. J Acquir Immune Defic Syndr and Hum Retrovirol 1995;10:386-390. This article discusses 175 injection-drug users screened for enrollment in a Phase II HIV vaccine trial. Experience suggests that recruitment of injection-drug users into HIV vaccine trials is feasible, that these persons can comprehend and complete informed consent procedures, and that the follow-up visit return-rate is not substantially less than noninjection-drug users.
42. Hollis JF, Satterfield S, Smith F, Fouad M, Allender PS, Borhani N. Charleston J, Hirlinger M, King N, Schultz R, Sousoulas BG on behalf of the TOHP Collaborative Research Group. Recruitment for phase II of the trials of hypertension prevention (TOHP). Ann Epidemiol 1995;5:140-148. Recruitment to a two-by-two-factorial designed trial of hypertension prevention was described. Direct mail accounted for 73% of those randomized; community screening, 12%, and media advertising,11%. Referrals from health-care providers were few. Prescreening improved recruitment efficiency. Mailings through interoffice mail systems were successful. Repeat mailings to the same lists were used successfully. Similar recruitment rates were observed among all racial-ethnic groups (20% minorities).
43. Hughes GH, Cutter G, Donahue R, Friedman GD, Hulley S, Hunkeler E, Jacobs DR Jr, Kiang L, Orden S, Pirie P, Tucker B, Wagenknecht L. Recruitment in the coronary artery disease risk development in young adults (CARDIA) study. Controlled Clin Trials 1987; 8:68S-73S. The recruitment of 5100 individuals 18-30 years of age for a longitudinal study of the evolution of coronary heart disease was done in four clinics. Telephone recruitment was the main method used by all clinics to reach and screen participants. Major challenges were the lengthy baseline visit of four and one-half hours, and the initial protocol requirement of equal representation across subgroups of age, sex, and race.
44. Hunninghake DB, Knoke J, LaDouceur M, Peterson F. Population characteristics according to recruitment source. Circulation 1982; 66:IV46-IV48. The considerable variability among the proportion of first protocol visits that led to entry in the Coronary Primary Prevention Trial, by recruitment source and center, is examined. Some of the reasons for these differences are explored. Several characteristics of the participants are analyzed to determine whether or not significant variability existed, and the results suggest that these characteristics could be used in selecting recruitment sources for clinical trials.
45. Hunninghake DB, Peterson F, LaDouceur M, Knoke J, Leon A. Recruitment from clinical studies. Circulation 1982;66:IV15-IV19. The recruitment campaign of the Coronary Primary Prevention Trial that was conducted with referrals from related clinical studies is highlighted. The combination of low cost and high efficiency make referrals from other clinical studies attractive. If such referrals are available, every effort should be made to maximize their use.
46. Hunter CP, Frelick RW, Feldman AR, Bavier AR, Dunlap WH, Ford L, Henson D, Macfarlane D, Smart CR, Yancik R, Yates JW. Selection factors in clinical trials: results from the community clinical oncology program physician's patient log. Cancer Treat Rep 1987;71:559-565. A brief history of the development and purpose of the Community Clinical Oncology Program is given, including its role in making available to the community oncologist and to their patients clinical research protocols. The article outlines the difficulty of selection, recruitment, and entry of cancer patients into protocols due to protocol requirements and the preference for treatment of the physician and patient.
47. Hypertension Detection and Follow-up Program Cooperative Group. Patient participation in a hypertension control program. JAMA 1978;239:1507-1515. In the Hypertension Detection and Follow-up Program, the largest standardized hypertension detection, follow-up, and treatment program to date in the United States, participation rates have been high at all stages. More than 75% of those with suspected hypertension at screening attended follow-up screening, and more than 80% of the 5314 hypertensive patients assigned to program treatment remained active at the end of one year. Efforts to maximize attendance and factors that might affect response rates are examined.
48. Kaluzny A, Brawley O, Garson-Angert D, Shaw J, Godley P, Warnecke R, Ford L. Assuring access to state-of-the-art care for U.S. minority populations: the first two years of the minority-based community clinical oncology program. J Natl Cancer Inst 1993;85:1945-1950. Initiated in September 1990 by the NCI, the Minority-Based Community Clinical Oncology Program (MBCCOP) attempted to expand the clinical trials network of the NCI in minority populations. During its first two years MBCCOP demonstrated its ability to accrue patients to protocols for cancer treatment, prevention, and control. Difficulties included working with a fragmented and deteriorating health-care environment, centers operating in environments characterized by socioeconomic decline and limited resources, barriers involving language, logistics, and the appropriateness of available protocols as well as the reluctance on the part of physicians to participate in protocol studies.
49. Kaslow RA, Ostrow DG, Detels R, Phair JP, Polk F, Rinaldo CR Jr. for the Multicenter AIDS Cohort Study. The multicenter AIDS cohort study: rationale, organization, and selected characteristics of the participants. Am J Epi 1987;126:310-318. This study recruited 5000 homosexual men through combinations of media, personal connections of both gay activists and early participants in the study, promotional events or offerings such as raffles or medical screening, and previous clinical contacts with largely gay medical practices or through research on other conditions in gay men. Each center offered protection of confidentiality of participants' identifying information through a federally authorized procedure providing immunity to subpoena or other legal proceedings.
50. King AC, Harris RB, Haskell WL. Effect of recruitment strategy on types of subjects entered into a primary prevention clinical trial. Ann Epidemiol 1994;4:312-320. This article compares a community media campaign and a random-digit-dial telephone survey in the identification of subjects for a primary prevention trial to evaluate strategies for increasing physical activity in sedentary men and women. Adherence rates did not differ by recruitment source. The media campaign was less expensive than the telephone survey; the survey method may identify a more representative population.
51. Kirscht JP, Haefner DP, Eveland JD. Public response to various written appeals to participate in health screening. Public Health Rep 1975;90:539-543. The effectiveness of health communications in relation to the message content and the communication medium used in the program is reported. Three different types of health messages (a neutral form, a threat form, and a positive form) were designed to encourage individuals to participate in a voluntary multiphase screening program. The results indicate that the positive message was significantly more effective in encouraging participation than either the neutral message or the threat version, especially for women.
52. Kusek JW, Coyne T, de Velasco A, Drabik MJ, Finlay RA, Gassman JJ, Kiefer S, Powers SN, Steinman TI. Recruitment experience in the full-scale phase of the modification of diet in renal disease study. Controlled Clin Trials 1993;14:538-557. This article describes the overall results of recruitment and means by which potential participants were identified. Strategies utilized review of medical records, physician referral, physician and patient booklets, national and local media, including newspapers, television, an 800 telephone number, public service announcements, paid advertising, stand-up posters with tear-off flyers, feature articles, press releases, television/radio interviews, and presentations by principal investigators.
53. Lee YJ. Interim recruitment goals in clinical trials. J Chronic Dis 1983;36:379-389. Statistical methods for determining a proper recruitment rate, duration of recruitment, and interim recruitment goals are proposed. Methods for projecting the final sample size attained and adjusting the recruitment duration at intervals are discussed. Seasonal adjustment methods are proposed.
54. Lerman C, Rimer BK, Daly M, Lustbader E, Sands C, Balshem A, Masny A, Engstrom P. Recruiting high-risk women into a breast cancer health promotion trial. Cancer Epidemiol Biomarkers Prev 1994;3:271-276. This article describes factors that influence entry into a breast cancer health promotion trial among high-risk women age 35 years and older. In general, married women with high educational levels and economic status were more likely to participate. Education level was a key determinant of the importance of other characteristics in the decision to participate.
55. Levenkron JC, Farquhar JW. Recruitment using mass media strategies. Circulation 1982;66:IV32-IV36. The media strategies that played an integral role in the recruitment effort of the Coronary Primary Prevention Trial are presented. The media were used for two purposes: (1) to augment diverse recruitment efforts and (2) to serve as independent recruitment sources. Nine centers recruited patients directly through newspapers, radio, television, or a combination of these methods. The results are reported.
56. Little JA. Recruitment from medical referrals and clinical laboratories. Circulation 1982;66:IV36-IV40. The ratio of initial contacts to study participants are compared for medical and clinical laboratory referrals to clinical trials. Both sources require a relatively low level of effort for the recruitment team; however, low yields preclude reliance on these sources for any but the smallest clinical trial.
57. Loescher LJ, Graham VE, Aickin M, Meyskens FL Jr, Surwit EA. Development of a contingency recruitment plan for a phase III chemoprevention trial of cervical dysplasia. Prog Clin Biol Res 1990;339:151-163. Contingency recruitment plans are necessary when unanticipated shortfalls in subject accrual occur. By requesting information from initial subjects recruited to CTDC, a framework was formulated for a contingency recruitment plan.
58. Luke RG for the Modification of Diet in Renal Disease Study Group. The modification of diet in renal disease study: design, methods, and results from the feasibility study. Am J Kidney Dis 1992;20:18-33. In this feasibility study recruitment was confined to reviewing patients' charts and referral from nephrologists in practice at each participating clinical center. Proposed recruitment activities for the full-scale study included referrals from nephrologists, internists, and general practitioners through publications and presentations. Patients known to have kidney disease were encouraged to enroll through a public relations campaign, including feature stories, public service announcement, and advertising.
59. Martin JF, Henderson WG, Zacharski LR, Rickles FR, Forman WB, Cornell CJ Jr, Forcier RJ, Edwards RL, Headley E, Kim SH. Accrual of patients into a multihospital cancer clinical trial and its implications on planning future studies. Am J Clin Oncol 1984;7:173-182. The results of patient screening for a therapeutic clinical trial are reported, and screening methods are described. Comparisons are made between excluded and included patients as well as between the projected and actual sample size. Concerns about generalizability are raised. The implications for planning future oncological cooperative trials are discussed.
60. Mattson ME, Curb JD, McArdle R. Participation in a clinical trial: the patient's point of view. Controlled Clin Trials 1985;6:156-167. The results of two surveys that were undertaken to obtain data on patients' perceptions of participation in a clinical trial are reported. The studies indicate that patients felt that the additional medical monitoring, the opportunity for a second opinion, and the reassurance that they received were important benefits; the perceived disadvantages centered on transportation problems and clinic waiting time.
61. McDearmon M, Bradford RH. Recruitment by the use of mass mailings. Circulation 1982;66:IV27-IV31. The use of direct mailings to recruit participants to the Coronary Primary Prevention Trial is examined. Direct mailings provided 6% of the initial contacts, 7% of the first protocol visits, and 6% of the entries in the trial. Mailings were sent to people identified through voter registration and driver's license lists, group membership, and direct-mail firms. Variable responses were obtained, but voter registration lists yielded the highest number of participants.
62. McKeown MB. Occupational screenings: recruitment of government employees. Circulation 1982;66:IV43-IV46. The occupational screenings of the Coronary Primary Prevention Trial, which involved 203 agencies that represented federal, state, and local governments, are described. Nine centers made use of this strategy, and the results suggest that screening government employees is costly and involves careful planning and complex arrangements.
63. McNeely EA, Clements SD. Recruitment and retention of the older adult into research studies. J Neurosci Nurs 1994;26:57-61. This article reviews the literature on the recruitment of older adult participants and presents in depth the challenges experienced by two nurse researchers working on a national multi-site intervention study of frailty and fall-related injuries in older persons through novel exercise regimens.
64. Melish JS. Recruitment by community screenings. Circulation 1982;66:IV20-IV23. The use of community screenings for recruitment to the Coronary Primary Prevention Trial is examined. Three categories of community screenings (locations, events, and organizations) provided 21% of the initial contacts and 14% of the first protocol visits and entries in the trial. The discussion includes the productivity of various screening efforts and recommendations for the planning and organization of community screenings in future clinical trials.
65. Millon-Underwood S, Sanders E, Davis M. Determinants of participation in state-of-the-art cancer prevention, early detection screening, and treatment trials among African-Americans. Cancer Nurs 1993;16:25-33. The article describes a survey (N = 220) of perceptions, attitudes, and beliefs related to participation by African-Americans in cancer prevention, diagnostic and/or treatment trials. One hundred percent of those surveyed believed that research programs and/or trials are available only to patients with disease. Besides demographic data, perceptions about medical research, benefits of participation, and motivations to participate are described.
66. Morse EV, Simon PM, Besch CL, Walker J. Issues of recruitment, retention, and compliance in community-based clinical trials with traditionally underserved populations. Appl Nurs Res 1995;8:8-14. Medically underserved populations frequently expect some of their primary care to be rendered as part of the clinical trial activity. Seemingly restrictive or exclusive protocols become less problematic in this circumstance. Clinic personnel sensitive to the problems presented by these individuals, e.g., HIV or AIDS patients, prevent or remove many of these barriers.
67. Neaton JD, Grimm RH Jr, Cutler JA. Recruitment of participants for the multiple risk factor intervention trial (MRFIT). Controlled Clin Trials 1987;8:41S-53S. In 44 months, a total of 361,662 age-eligible men were screened and 12,866 were randomized in MRFIT, a primary prevention trial designed to test the effect of multiple interventions on mortality from coronary heart disease. Recruitment success followed these points: select experienced investigators, have one person in each clinic responsible for coordinating recruitment activities, phase entry of new clinics into the study, monitor and report recruitment rates on a regular basis, discuss recruitment at steering committee meetings, and solve recruitment problems through clinical center site visits.
68. Newburg SM, Holland AE, Pearce LA. Clinical methods: motivation of subjects to participate in a research trial. Appl Nurs Res 1992;5:9-104. This study utilized a survey sent to 146 randomized patients enrolled in two midwestern centers for the SPAF study. Over 95% of the patients responded. The two motivators for participation most often listed were the importance of research in improving medicine and helping others in the future. Other motivators highly rated included preventing stroke, maintaining health security and interest in health education, and affinity for the nurse coordinator and the physician investigator.
69. Newcomb PA, Love RR, Phillips JL, Buckmaster BJ. Using a population-based cancer registry for recruitment in a pilot cancer control study. Prev Med 1990;19:61-65. One hundred forty women were randomized to a toxicity trial of tamoxifen using a population-based cancer registry. Usual recruitment strategies were unlikely to be effective because of a small number of screenees and restrictive eligibility requirements. Women were successfully recruited in two years, using letters signed by their follow-up physicians: 18% of women contacted were randomized. Registries contain demographic information, diagnostic details, and treatment history, allowing easy identification and prescreening of potential subjects.
70. Norton MC, Breitner JCS, Welsh KA, Wyse BW. Characteristics of nonresponders in a community survey of the elderly. J Am Geriatr Soc 1994;42:1252-1256. A cognitive status pilot study was conducted in which initial response to a letter and follow-up phone call was 63%. Face-to-face contact achieved a participation rate of 93%. The substantial number of subjects later converted from nonresponders to responders provided insight into the correlates of nonresponse in cognitive screening surveys. Findings showed nonresponders in community surveys of the elderly to be more frequently cognitively impaired. Elderly persons who do not respond to mail or telephone can still be recruited through face-to-face contact.
71. Novak E, Seckman CE, Stewart RD. Motivations for volunteering as research subjects. J Clin Pharmacol 1977;17:365-371. The results of a questionnaire on the willingness to take part in simple drug testing unrelated to personal illness are reported. The subjects were asked to state whether they would participate in a hypothetical research study and to indicate the reasons for their choice and conditions for participation. More than 60% of the respondents stated that they would participate in the proposed study.
72. Ogilvie JT, Mishkel NR, Mishkel MA, Welch VE, Insull W Jr, Probstfield JL, Gotto AM. Occupational screenings: recruitment from private industry. Circulation 1982;66:IV40-IV43. The use of occupational screenings for recruitment to the Coronary Primary Prevention Trial is reported. Occupational screenings provided 26% of the initial contacts, 20% of the first protocol visits, and 17% of the entries for the trial. The topics discussed include publicity for screening programs, reasons some industries declined to participate, characteristics of the recruitment staff, and reporting lipid results to the screening participants.
73. Penn ZJ, Steer PJ. Reasons for declining participation in a prospective randomized trial to determine the optimum mode of delivery of the preterm breech. Controlled Clin Trials 1990;11:226-231. The feasibility of performing a randomized controlled trial to compare elective with selective Cesarean delivery for preterm breech infants was assessed by asking consultant gynecologists in 36 hospitals if they would be willing to participate in such a trial. In 11 of these hospitals, universal support was not obtained. Primary reasons were insufficient staff time to properly obtain informed consent, and difficulties with availability and/or skill of medical staff for delivery.
74. Petrovitch H, Byington R, Bailey G, Borhani P, Carmody S, Goodwin L, Johnson A, Johnson P, Jones M, Levin J, Sugars C, Probstfield JL. Screening and recruitment experience in the full scale SHEP trial. Hypertension 1991;17:II16-II23. Recruiting older individuals to trials requires that a positive image of older adults be projected by the study. Transportation is a specific issue in the recruitment of older adults. The recruitment of men and women reflected the prevalence by gender of the disease process. Timely initiation of recruitment effort and multiple interlocking strategies are emphasized as part of the overall recruitment plan. Caution is issued regarding pilot data; they may be misleading.
75. Probstfield JL, Wittes JT, Hunninghake DB. Recruitment in NHLBI population-based studies and clinical trials: data analysis and survey results. Controlled Clin Trials 1987;8:141S-149S. A single summary statistic for measuring the efficiency of recruitment in randomized clinical trials and population-based studies is proposed and applied to completed NHLBI studies. Clinical trial sample size calculations are predicated on continuous accrual during the planned recruitment period. This provides a basis for comparison of recruitment efficiency against a standard but not amongst trials. Information is provided on a "core of recruitment data" proposed for collection in all trials to further recruitment research.
76. Probstfield JL. The clinical trial prerandomization compliance (adherence) screen. In: Cramer JA, Spilker B, eds. Patient Compliance in Medical Practice and Clinical Trials. New York: Raven Press; 1991:323-334. Recruitment and adherence are very closely linked since those recruited must be followed to study completion as the inception cohort. This article details the use of run-in and test-dosing procedures during the recruitment period as a potential means of improving adherence during the follow-up period. The indications and contra-indications for the use of each procedure are discussed. There is a clear impact on recruitment in terms of cost and both screenees and staff burden.
77. Quick AM, Khaw PT, Elkington AR. Problems encountered in recruiting patients to an ophthalmic drug trial. Br J Ophthalmol 1989;73:432-434. The problems encountered in two clinical trials to assess the efficacy of two topical beta-blocker preparations are discussed in detail. Ineligibility and refusal rates are documented, and comparisons to the experience of other ophthalmic studies and to cardiac studies are made. The identified patient pool must be reduced considerably when estimating recruitment yield, possibly by a factor of ten.
78. Roberson NL. Clinical trial participation viewpoints from racial/ethnic groups. Cancer 1991;74:2687-2691. A total of 28 African-Americans, Hispanics, and Native Americans were interviewed over the telephone to obtain their opinions about clinical trial participation. Survey results demonstrated that interviewees believed that participation could be beneficial, although some cultural factors were believed to influence participation. A recruitment plan should be tailored to the target group, be designed to reflect trust in the medical care-givers and present the study as credible, and be implemented through a continuing educational process.
79. Ross MW, Jeffords K, Gold J. Reasons for entry into and understanding of HIV/ AIDS clinical trials: a preliminary study. AIDS Care 1993;6:77-82. Thirty-two men who participated in a trial of Zidovudine listed their clinic doctor as the main source of influence to enter the trial. Importance for self was rated lowest. The study suggests that participation was for altruistic rather than personal reasons and that participants had realistic perceptions of outcomes. The importance of the readability and level of knowledge gained from the consent form is discussed.
80. Rubinstein LV, Gail MH. Monitoring rules for stopping accrual in comparative survival studies. Controlled Clin Trials 1982;3:325-343. Rules for monitoring survival studies are presented that allow for early termination of accrual if evidence mounts against one therapy. These rules for stopping accrual do not detectably perturb the final analysis, which includes a log rank test of no treatment effect and an estimation of the log relative hazard with confidence intervals. These methods take advantage of the reservoir of information represented by patients who are still at risk at the time accrual ceases.
81. Rudick C, Anthonisen NR, Manfreda J. Recruiting healthy participants for a large clinical trial. Controlled Clin Trials 1993;14:68S-79S. Direct mail, direct mail with telephone follow-up, workplace screening, shopping-mall recruitment, community events, media, and other methods were used to recruit participants to a study of strategies to prevent chronic obstructive pulmonary disease. The most successful methods for identifying initial screenees in this Canadian center were direct mail with follow-up telephoning (50%) and workplace screening (14%).
82. Sager Ashery R, McAuliffe WE. Implementation issues and techniques in randomized trials of outpatient psychosocial treatments for drug abusers: recruitment of subjects. Am J Drug Alcohol Abuse 1992;18:305-329. This article examines nine randomized clinical trials of outpatient psychosocial treatments for drug abusers, identifies common problems found when trying to recruit from these populations, and suggests approaches to solving these problems. Areas addressed include underestimating difficulty of recruitment, taking action too late, the need for a large sample size, the need to find a specific abuse population, gaining access to that population, motivating the patient to participate, dealing with the fear of both therapists and patients of being "guinea pigs," the eligibility criteria limiting the population further, and the difficulty of developing and maintaining referral sources.
83. Schoenberger JA. Recruitment experience in the aspirin myocardial infarction study (AMIS). Controlled Clin Trials 1987;8:74S-78S. The Aspirin Myocardial Infarction Study (AMIS) successfully used review of patient records (40%), self-referral through media (36%), physician referral (16%), and other (9%) to recruit study participants. Recruitment was completed in 14 months (goal of 12 months) with half the patients randomized in the last 5 months. This resulted in a large percentage of total annual follow-up visits occurring at certain times of the year. Careful planning of multiple recruitment strategies based on explicit eligibility criteria before the initiation of startup is recommended.
84. Schrott HG, Merideth N. Recruitment by screening entire communities: the Iowa lipid research clinic experience. Circulation 1982;66:IV23-IV26. The usefulness of screening entire communities is reviewed. The process included three components: access to names and addresses of age-eligible persons who could be contacted through a direct-mail announcement, support from local media and community leaders, and effective on-site screening teams. Responses to direct mailings were enhanced by a coordinated media campaign in which print media proved more effective than radio or television.
85. Shea S, Bigger JT Jr, Campion J, Fleiss JL, Rolnitzky LM, Schron E, Gorkin L, Hamdshaw K, Kinney MR, Branyon M. Enrollment in clinical trials: institutional factors affecting enrollment in the cardiac arrhythmia suppression trial (CAST). Controlled Clin Trials 1992;13:466-486. Institutional factors are identified as affecting recruitment in this secondary prevention trial. The most important factor positively influencing recruitment was the proportion of C AST-eligible patients at a site not being cared for by private attending physicians but by fellows, house-staff, or service attending physicians. Other factors included the number of days a CAST nurse-coordinator was present at the site and whether or not the nurse coordinator was working for other clinical trials. All factors identified accounted for only 40% of the variance in enrollment rates.
86. Silagy CA, Campion K, McNeil JJ, Wrosam B, Donnan GA, Tonkin AM. Comparison of recruitment strategies for a large-scale clinical trial in the elderly. J Clin Epidemiol 1991;44:1105-1114. This article describes the recruitment strategies tested and used in a pilot study for PACE (Prevention by Aspirin of Cardiovascular disease in the Elderly) in Australia. Four hundred subjects were recruited using (1) electoral rolls, (2) four general practices, and (3) a community-based approach involving three components: retirement villages, local media, and posters. The authors note that these strategies were applied in Australia where there are universal national health programs and where all citizens are registered with, and served by, general practitioners.
87. Stern MP. Recruitment of participants from blood banks. Circulation 1982;66:IV10-IV15. The recruitment experience of the Coronary Primary Prevention Trial in collaboration with blood banks is reported. Blood banks were used to some extent by all the centers and provided 26% of the initial contacts and 15% of the first protocol visits and entries for the trial. Recommendations for successful collaborations are provided.
88. Sunderraj P, Peiris C. Recruitment of patients to a glaucoma drug trial in a district general hospital. Eye 1991;5:329-332. This paper reports the difficulties experienced in the identification and recruitment of 21 patients with ocular hypertension or primary open-angle glaucoma to participate in a clinical trial of two topical beta blockers. Potential subjects were identified by reviewing patient records.
89. Swanson GM, Ward AJ. Recruiting minorities into clinical trials: toward a participant-friendly system. J Natl Cancer Inst 1995;87:1747-1759. This paper describes current knowledge about the recruitment of participants from diverse populations, specifically ethnic and racial minorities, into therapeutic or prevention clinical trials. Barriers to recruitment of minority participants and minority physician participation, barriers inherent in study design, researcher bias, and strategies for recruitment, study design, and cost issues are discussed.
90. Taylor KM, Kelner M. Interpreting physician participation in randomized clinical trial: the physician orientation profile. J Health Social Behav 1987;28:389-400. The cooperation and participation of physicians are often essential to the success of a clinical trial. This study reports on the development and use of the Physician Orientation Profile, a 30-item typology that evaluates physicians' attitudes toward enrolling patients in randomized clinical trials. This profile may make it possible to measure a physician's willingness to participate in scientific research and thus be used as a predictor of a physician's response and cooperation when invited to participate in such trials.
91. Taylor KM, Margolese RG, Soskolne CL. Physicians' reasons for not entering eligible patients in a randomized clinical trial of surgery for breast cancer. N Engl J Med 1984;310:1363-1367. The reasons principal investigators chose not to enter patients in the National Surgical Adjuvant Project for Breast and Bowel Cancers are discussed. A survey of participating physicians offered the following explanations: concern that the doctor-patient relationship would be affected, difficulty with informed consent, dislike of open discussions that involved uncertainty, perceived conflict between the roles of scientist and clinician, practical difficulties in following procedures, and feelings of personal responsibility if the treatments were found to be unequal.
92. Taylor KM, Shapiro M, Soskolne CL, Margolese RG. Physician response to informed consent regulations for randomized clinical trials. Cancer 1987;60:1415-1422. Reluctance by physicians to enter their patients into clinical trials is cited as the most significant factor in the failure to complete randomized clinical trials successfully. Responses to a 30-item survey were collected from 170 breast cancer specialists in eight countries to determine their treatment philosophies and their overall view of the current practice of medicine. The data suggest that physicians interpret the obtaining of informed consent for clinical trials as a potential interference with their role as health-care provider.
93. Thornquist MD, Patrick DL, Omenn GS. Participation and adherence among older men and women recruited to the beta-carotene and retinol efficacy trial (CARET). Gerontologist 1991;31:593-597. The article discusses the results from two pilot studies of CARET (a multi-center cancer prevention trial) participants to determine if there was a significant difference as a function of age and gender in participation and adherence rates in older adults. Negligible difference was found by age in response to recruitment mailings, drop-out during the enrollment process, and drop-out after randomization. Men had a lower drop-out rate than women, but the differences were not statistically significant.
94. Vogt TM, Ireland CC, Black D, Camel G, Hughes G. Recruitment of elderly volunteers for a multicenter clinical trial: the SHEP pilot study. Controlled Clin Trials 1986;7:118-133. An overview of the recruitment experience for the Systolic Hypertension in the Elderly Program (SHEP) pilot study is presented. The paper examines the process of screening approximately 75,000 persons and enrolling 551 individuals 60 years old or older who had isolated systolic hypertension into a double-blind controlled clinical trial. The degree to which the U.S. general population, the screened population, and the enrolled population resemble each other is discussed.
95. Vollmer WM, Hertert SK, Allison MJ. Recruiting children and their families for clinical trials: a case study. Controlled Clin Trials 1992;13:315-320. The article describes the recruitment of 226 families for participation in a randomized trial that examined the effectiveness of alternative strategies for the management of pediatric asthma. Subjects (children, age 4-14 years) were identified through review of emergency and ambulatory care logs, computerized inpatient records and computerized outpatient pharmacy records, and physician referral. The effectiveness and the problems of each recruitment method are discussed, including targeted mailings and follow-up telephone calls, no-shows, Saturday appointments, and retention.
96. Wadland WC, Hughes JR, Secker-Walker RH, Bronson DL, Fenwick J. Recruitment in a primary care trial on smoking cessation. Fam Med 1990;22:201-204. Recruitment rates during a randomized clinical trial on smoking cessation are compared for an academic medical practice and a private practice. The rates of enrollment, refusal, and drop-out during recruitment, and comparisons of recruitment using different personnel and informed-consent procedures, are presented. This paper provides evidence that recruitment from private practice appears to be no worse than from academic centers.
97. Walden CE, McCann BS, Retzlaff B, Dowdy A, Hanson M, Fish B, Fitzpatrick V, Follette W, Parker D, Grey G, Cooper M, Knopp RH. Alternative fat-restricted diets for hypercholesterolemia and combined hyperlipidemia: feasibility, design, subject recruitment, and baseline characteristics of the dietary alternatives study. J Am Coll Nutr 1991;10:429-442. The recruitment of males at the Boeing Company for a dietary-change intervention related to heart disease is discussed. Screening and recruitment were supported by and conducted at the company medical department, including a nurse, a phlebotomist, space for diet classes, underwater weighing, logistics, mailing, and other support services. Screening spanned an 18-month period. This study concludes that recruiting a large cohort of hypercholesterolemic and combined hyperlipidemic subjects from an industrial workforce is feasible in a restricted time frame.
98. Williford WO, Bingham SF, Weiss DG, Collins JF, Rains KT, Krol WF. The "constant intake rate" assumption in interim recruitment goal methodology for multicenter clinical trials. J Chronic Dis 1987;40:2977-3007. This paper explores methodology to predict recruitment of a predetermined number of patients during a specified time period. An assumption made by previous statistical methodology is that patients are recruited at a constant rate over the entire length of the prespecified interval. This paper uses data generated from nine multihospital clinical trials between 1975 and 1982 to examine this assumption and the appropriateness of its use. A Bayesian approach is proposed, which assumes a nonconstant patient intake rate.