TY - JOUR
T1 - Success of masking 5% povidone-iodine treatment
T2 - The reducing adenoviral patient infected days study
AU - Whiteside, Meredith M.
AU - Shorter, Ellen S.
AU - Margolis, Mathew S.
AU - Alvi, Fatima
AU - Huecker, Julia B.
AU - Than, Tammy P.
AU - Migneco, Mary K.
AU - Harthan, Jennifer S.
AU - Morettin, Christina E.
AU - Hartwick, Andrew T.E.
AU - Johnson, Spencer D.
AU - Perera, Chamila D.
AU - Gordon, Mae O.
N1 - Funding Information:
Funding/Support: Foundation for the National Institutes of Health (5 R21 EY030524 and 5 R34 EY023633), Core grants P30 EY001792 (University of Illinois), P30 EY002687 (Washington University) and an unrestricted grant from Research to Prevent Blindness.
Publisher Copyright:
Copyright © 2021 American Academy of Optometry.
PY - 2021
Y1 - 2021
N2 - SIGNIFICANCE: The effectiveness of masking is rarely evaluated or reported in single- or double-masked clinical trials. Knowledge of treatment assignment by participants and clinicians can bias the assessment of treatment efficacy. PURPOSE: This study aimed to evaluate the effectiveness ofmasking in a double-masked trial of5%povidone-iodine for the treatment of adenoviral conjunctivitis. METHODS: The Reducing Adenoviral Patient Infected Days study is a double-masked, randomized trial comparing a one-time, in-office administration of 5%povidone-iodine with artificial tears for the treatment of adenoviral conjunctivitis. Masking was assessed by asking participants and masked clinicians at designated time points if they believed the treatment administered was povidone-iodine or artificial tears, or if they were unsure. Adequacy of masking was quantified using a modified Bang Blinding Index. RESULTS: Immediately after treatment, 34%of participants who received povidone-iodine and 69%of those who received artificial tears guessed incorrectly or were unsure of their treatment (modified Bang Indices of 0.31 and -0.38, respectively). On day 4, 38%of the povidone-iodine participants and 52%of the artificial tear participants guessed incorrectly or were unsure of their treatment (modified Bang Indices of 0.24 and -0.05, respectively), indicating adequate and ideal masking. On days 1, 4, 7, 14, and 21,masked clinicians guessed incorrectly or were unsure of treatment in 53%, 50%, 40%, 39%, and 42% among povidone-iodine participants compared with 44%, 35%, 38%, 35%, and 39% among artificial tears participants, respectively. The modified Bang Indices for clinician masking in the povidone-iodine group ranged from -0.05 to 0.25 and from 0.13 to 0.29 in the artificial tears group. CONCLUSIONS: Masking of participants and clinicians was adequate. Successful masking increases confidence that subjective measurements are not biased.We recommend quantitative assessment and reporting the effectiveness of masking in ophthalmic clinical trials.
AB - SIGNIFICANCE: The effectiveness of masking is rarely evaluated or reported in single- or double-masked clinical trials. Knowledge of treatment assignment by participants and clinicians can bias the assessment of treatment efficacy. PURPOSE: This study aimed to evaluate the effectiveness ofmasking in a double-masked trial of5%povidone-iodine for the treatment of adenoviral conjunctivitis. METHODS: The Reducing Adenoviral Patient Infected Days study is a double-masked, randomized trial comparing a one-time, in-office administration of 5%povidone-iodine with artificial tears for the treatment of adenoviral conjunctivitis. Masking was assessed by asking participants and masked clinicians at designated time points if they believed the treatment administered was povidone-iodine or artificial tears, or if they were unsure. Adequacy of masking was quantified using a modified Bang Blinding Index. RESULTS: Immediately after treatment, 34%of participants who received povidone-iodine and 69%of those who received artificial tears guessed incorrectly or were unsure of their treatment (modified Bang Indices of 0.31 and -0.38, respectively). On day 4, 38%of the povidone-iodine participants and 52%of the artificial tear participants guessed incorrectly or were unsure of their treatment (modified Bang Indices of 0.24 and -0.05, respectively), indicating adequate and ideal masking. On days 1, 4, 7, 14, and 21,masked clinicians guessed incorrectly or were unsure of treatment in 53%, 50%, 40%, 39%, and 42% among povidone-iodine participants compared with 44%, 35%, 38%, 35%, and 39% among artificial tears participants, respectively. The modified Bang Indices for clinician masking in the povidone-iodine group ranged from -0.05 to 0.25 and from 0.13 to 0.29 in the artificial tears group. CONCLUSIONS: Masking of participants and clinicians was adequate. Successful masking increases confidence that subjective measurements are not biased.We recommend quantitative assessment and reporting the effectiveness of masking in ophthalmic clinical trials.
UR - http://www.scopus.com/inward/record.url?scp=85106554167&partnerID=8YFLogxK
U2 - 10.1097/OPX.0000000000001691
DO - 10.1097/OPX.0000000000001691
M3 - Article
C2 - 33973917
AN - SCOPUS:85106554167
SN - 1040-5488
VL - 98
SP - 469
EP - 475
JO - Optometry and Vision Science
JF - Optometry and Vision Science
IS - 5
ER -