TY - JOUR
T1 - Effect of telephone calls from a centralized coordinating center on participant retention in a randomized clinical trial
AU - Glassman, Adam R.
AU - Beaulieu, Wesley T.
AU - Stockdale, Cynthia R.
AU - Beck, Roy W.
AU - Bressler, Neil M.
AU - Labriola, Leanne T.
AU - Melia, Michele
AU - Oliver, Kristina
AU - Sun, Jennifer K.
N1 - Funding Information:
The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Supported through a cooperative agreement between the National Eye Institute and the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health (grant nos EY14231, EY23207, and EY18817). Genentech provided ranibizumab for the study and funds to the DRCR Retina Network to defray the study’s clinical site costs. The National Institutes of Health participated in oversight of the conduct of the study and review of the manuscript but not directly in the design or conduct of the study nor in the collection, management, analysis, or interpretation of the data; preparation, review, or approval of the manuscript; or decision to submit the manuscript for publication. Per the DRCR Retina Network Industry Collaboration Guidelines (available at http://www.drcr.net ), the DRCR Retina Network had complete control over the design of the protocol, ownership of the data, and all editorial content of presentations and publications related to the protocol. A complete list of all DRCR Retina Network investigator financial disclosures can be found at www.drcr.net .
Funding Information:
The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Supported through a cooperative agreement between the National Eye Institute and the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health (grant nos EY14231, EY23207, and EY18817). Genentech provided ranibizumab for the study and funds to the DRCR Retina Network to defray the study?s clinical site costs. The National Institutes of Health participated in oversight of the conduct of the study and review of the manuscript but not directly in the design or conduct of the study nor in the collection, management, analysis, or interpretation of the data; preparation, review, or approval of the manuscript; or decision to submit the manuscript for publication. Per the DRCR Retina Network Industry Collaboration Guidelines (available at http://www.drcr.net), the DRCR Retina Network had complete control over the design of the protocol, ownership of the data, and all editorial content of presentations and publications related to the protocol. A complete list of all DRCR Retina Network investigator financial disclosures can be found at www.drcr.net.
Publisher Copyright:
© The Author(s) 2020.
PY - 2020/4/1
Y1 - 2020/4/1
N2 - Background/Aims: In clinical trials, participant retention is critical to reduce bias and maintain statistical power for hypothesis testing. Within a multi-center clinical trial of diabetic retinopathy, we investigated whether regular phone calls to participants from the coordinating center improved long-term participant retention. Methods: Among 305 adults in the Diabetic Retinopathy Clinical Research Retina Network Protocol S randomized trial, 152 participants were randomly assigned to receive phone calls at baseline, 6 months, and annually through 3 years (annual contact group) while 153 participants were assigned to receive a phone call at baseline only (baseline contact group). All participants could be contacted if visits were missed. The main outcomes were visit completion, excluding deaths, at 2 years (the primary outcome time point) and at 5 years (the final time point). Results: At baseline, 77% (117 of 152) of participants in the annual contact group and 76% (116 of 153) in the baseline contact group were successfully contacted. Among participants in the annual contact group active at each annual visit (i.e. not dropped from the study or deceased), 85% (125 of 147), 79% (108 of 136), and 88% (110 of 125) were contacted successfully by telephone around the time of the 1-, 2-, and 3-year visits, respectively. In the annual and baseline contact groups, completion rates for the 2-year primary outcome visit were 88% (129 of 147) versus 87% (125 of 144), respectively, with a risk ratio of 1.01 (95% confidence interval: 0.93–1.10, p =.81). At 5 years, the final study visit, participant completion rates were 67% (96 of 144) versus 66% (88 of 133) with a risk ratio of 1.01 (95% confidence interval = 0.85–1.19, p =.93). At 2 years, the completion rate of participants successfully contacted at baseline was 89% (202 of 226) versus 80% (52 of 65) among those not contacted successfully (risk ratio = 1.12, 95% confidence interval = 0.98–1.27, p =.09); at 5 years, the completion percentages by baseline contact success were 69% (148 of 213) versus 56% (36 of 64; risk ratio = 1.24, 95% confidence interval = 0.98–1.56, p =.08). Conclusion: Regular phone calls from the coordinating center to participants during follow-up in this randomized clinical trial did not improve long-term participant retention.
AB - Background/Aims: In clinical trials, participant retention is critical to reduce bias and maintain statistical power for hypothesis testing. Within a multi-center clinical trial of diabetic retinopathy, we investigated whether regular phone calls to participants from the coordinating center improved long-term participant retention. Methods: Among 305 adults in the Diabetic Retinopathy Clinical Research Retina Network Protocol S randomized trial, 152 participants were randomly assigned to receive phone calls at baseline, 6 months, and annually through 3 years (annual contact group) while 153 participants were assigned to receive a phone call at baseline only (baseline contact group). All participants could be contacted if visits were missed. The main outcomes were visit completion, excluding deaths, at 2 years (the primary outcome time point) and at 5 years (the final time point). Results: At baseline, 77% (117 of 152) of participants in the annual contact group and 76% (116 of 153) in the baseline contact group were successfully contacted. Among participants in the annual contact group active at each annual visit (i.e. not dropped from the study or deceased), 85% (125 of 147), 79% (108 of 136), and 88% (110 of 125) were contacted successfully by telephone around the time of the 1-, 2-, and 3-year visits, respectively. In the annual and baseline contact groups, completion rates for the 2-year primary outcome visit were 88% (129 of 147) versus 87% (125 of 144), respectively, with a risk ratio of 1.01 (95% confidence interval: 0.93–1.10, p =.81). At 5 years, the final study visit, participant completion rates were 67% (96 of 144) versus 66% (88 of 133) with a risk ratio of 1.01 (95% confidence interval = 0.85–1.19, p =.93). At 2 years, the completion rate of participants successfully contacted at baseline was 89% (202 of 226) versus 80% (52 of 65) among those not contacted successfully (risk ratio = 1.12, 95% confidence interval = 0.98–1.27, p =.09); at 5 years, the completion percentages by baseline contact success were 69% (148 of 213) versus 56% (36 of 64; risk ratio = 1.24, 95% confidence interval = 0.98–1.56, p =.08). Conclusion: Regular phone calls from the coordinating center to participants during follow-up in this randomized clinical trial did not improve long-term participant retention.
KW - Retention
KW - loss to follow-up
KW - multi-center randomized clinical trial
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U2 - 10.1177/1740774519894229
DO - 10.1177/1740774519894229
M3 - Article
C2 - 31984762
AN - SCOPUS:85078790772
SN - 1740-7745
VL - 17
SP - 195
EP - 201
JO - Clinical Trials
JF - Clinical Trials
IS - 2
ER -