J Knee Surg
DOI: 10.1055/a-2179-8281
Original Article

Exploring Differences in Screening and Enrollment Metrics in Orthopaedic Clinical Trials

Laura Stiegel
1   Department of Orthopaedic Surgery, Cleveland Clinic Foundation, Cleveland, Ohio
Anabelle Visperas
1   Department of Orthopaedic Surgery, Cleveland Clinic Foundation, Cleveland, Ohio
1   Department of Orthopaedic Surgery, Cleveland Clinic Foundation, Cleveland, Ohio
Alison Klika
1   Department of Orthopaedic Surgery, Cleveland Clinic Foundation, Cleveland, Ohio
› Author Affiliations


The success of any clinical trial relies heavily on patient recruitment and retention. The purpose of this study was to review screening and enrollment metrics for orthopaedic clinical trials, comparing different patient populations to determine common challenges to recruitment and differences in rates of enrollment. Screening logs and study trackers were manually reviewed for four clinical trials at a single academic institution and included randomized controlled trials (RCTs) and an observational study. Data extracted from these documents included the number of patients screened, number excluded and reasons for exclusion, number enrolled, number of withdrawn and reason. Of the four trials reviewed, the point-of-care diagnostic test had the highest number of patients excluded and the lowest patient refusal rate. Refusal rates were highest in the venous thromboembolism prophylaxis study and enrollment rates were the lowest in the RCT of drug treatments and the highest rate in the observational study. The success of the trial relies on the ability to recruit patients and factors need to be considered when recruiting participants including sample size requirements and inclusion and exclusion criteria. These data provide some insights into the patient recruitment experience at our institution with different patient populations and study types, highlighting key points to be aware of when planning for an orthopaedic clinical trial.

Publication History

Received: 27 April 2023

Accepted: 20 September 2023

Accepted Manuscript online:
21 September 2023

Article published online:
03 November 2023

© 2023. Thieme. All rights reserved.

Thieme Medical Publishers, Inc.
333 Seventh Avenue, 18th Floor, New York, NY 10001, USA

  • References

  • 1 Bose D, Saha S, Saxena U, Kesari H, Thatte UM, Gogtay NJ. Factors influencing recruitment and retention of participants in clinical studies conducted at a tertiary referral center: A five-year audit. Perspect Clin Res 2020; 11 (02) 81-85
  • 2 Fogel DB. Factors associated with clinical trials that fail and opportunities for improving the likelihood of success: a review. Contemp Clin Trials Commun 2018; 11: 156-164
  • 3 Piuzzi N, Chughtai M, Khlopas A. et al. Early termination of randomized clinical trials in orthopaedics. Surg Technol Int 2017; 30: 290-294
  • 4 Anderson D. A Guide to Patient Recruitment – Today's Best Practices and Proven Strategies. Boston, MA: Center Watch Inc.; 2001
  • 5 Wong SE, North SA, Sweeney CJ, Stockler MR, Sridhar SS. Screen failure rates in contemporary randomized clinical phase II/III therapeutic trials in genitourinary malignancies. Clin Genitourin Cancer 2017; 17: 30274-4
  • 6 Rosa C, Campbell ANC, Miele GM, Brunner M, Winstanley EL. Using e-technologies in clinical trials. Contemp Clin Trials 2015; 45 (Pt A): 41-54
  • 7 Lovato LC, Hill K, Hertert S, Hunninghake DB, Probstfield JL. Recruitment for controlled clinical trials: literature summary and annotated bibliography. Control Clin Trials 1997; 18 (04) 328-352
  • 8 Elm JJ, Palesch Y, Easton JD. et al. Screen failure data in clinical trials: are screening logs worth it?. Clin Trials 2014; 11 (04) 467-472
  • 9 Rønsbo TN, Laigaard J, Pedersen C, Mathiesen O, Karlsen APH. Adherence to participant flow diagrams in trials on postoperative pain management after total hip and knee arthroplasty: a methodological review. Trials 2021; 22 (01) 280
  • 10 Moher D, Hopewell S, Schulz KF. et al. CONSORT 2010 explanation and elaboration: updated guidelines for reporting parallel group randomised trials. BMJ 2010; 340: c869
  • 11 Moher D, Jones A, Lepage L. Use of the CONSORT statement and quality of reports of randomized trials: a comparative before-and-after evaluation. JAMA 2001; 285 (15) 1992-1995
  • 12 Charlson ME, Horwitz RI. Applying results of randomised trials to clinical practice: impact of losses before randomisation. Br Med J (Clin Res Ed) 1984; 289 (6454) 1281-1284
  • 13 Travers J, Marsh S, Williams M. et al. External validity of randomised controlled trials in asthma: to whom do the results of the trials apply?. Thorax 2007; 62 (03) 219-223
  • 14 Gabriel SE, Normand SLT. Getting the methods right–the foundation of patient-centered outcomes research. N Engl J Med 2012; 367 (09) 787-790
  • 15 Madan A, Tracy S, Reid R, Henry A. Recruitment difficulties in obstetric trials: A case study and review. Aust New Zeal J Obstet Gynaecol 2014; 54 (06) 546-552
  • 16 Dekkers OM, von Elm E, Algra A, Romijn JA, Vandenbroucke JP. How to assess the external validity of therapeutic trials: a conceptual approach. Int J Epidemiol 2010; 39 (01) 89-94
  • 17 Emara AK, Klika AK, Piuzzi NS. Evidence-based orthopedic surgery-from synthesis to practice. JAMA Surg 2020; 155 (11) 1009-1010
  • 18 Walters SJ, Bonacho Dos Anjos Henriques-Cadby I, Bortolami O. et al. Recruitment and retention of participants in randomised controlled trials: a review of trials funded and published by the United Kingdom Health Technology Assessment Programme. BMJ Open 2017; 7 (03) e015276
  • 19 Jones RH, White H, Velazquez EJ. et al. STICH (surgical treatment for ischemic heart failure) trial enrollment. J Am Coll Cardiol 2010; 56 (06) 490-498
  • 20 Lincoff AM, Tardif JC, Neal B. et al. Evaluation of the dual peroxisome proliferator-activated receptor α/γ agonist aleglitazar to reduce cardiovascular events in patients with acute coronary syndrome and type 2 diabetes mellitus: rationale and design of the AleCardio trial. Am Heart J 2013; 166 (03) 429-434
  • 21 Lincoff AM, Tardif JC, Schwartz GG. et al; AleCardio Investigators. Effect of aleglitazar on cardiovascular outcomes after acute coronary syndrome in patients with type 2 diabetes mellitus: the AleCardio randomized clinical trial. JAMA 2014; 311 (15) 1515-1525
  • 22 Schroen AT, Petroni GR, Wang H. et al. Preliminary evaluation of factors associated with premature trial closure and feasibility of accrual benchmarks in phase III oncology trials. Clin Trials 2010; 7 (04) 312-321
  • 23 Laaksonen N, Varjonen JM, Blomster M. et al. Assessing an electronic health record research platform for identification of clinical trial participants. Contemp Clin Trials Commun 2020; 21: 100692
  • 24 Cassileth BR, Lusk EJ, Miller DS, Hurwitz S. Attitudes toward clinical trials among patients and the public. JAMA 1982; 248 (08) 968-970