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Glasses Against Transmission of SARS-CoV-2 (COVID-19) in the Community

The GLasses Against Transmission of SARS-CoV-2 (COVID-19) in the communitY (GLASSY) Trial: A Pragmatic Randomized Trial

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05217797
Acronym
GLASSY
Enrollment
3717
Registered
2022-02-01
Start date
2021-02-02
Completion date
2022-12-01
Last updated
2023-11-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

COVID-19, Respiratory Tract Infections

Keywords

COVID-19 Prevention Protection

Brief summary

In this trial the researchers plan to recruit 25,000 volunteers to be randomly allocated either wearing sunglasses or ordinary glasses in public spaces where they are close to other people, or not wear glasses in such circumstances. For each participant the trial period is 2 weeks, after which they will be asked to complete a brief questionnaire which includes questions about results of COVID-19 tests during the trial period.

Detailed description

A systematic review of observational studies indicated that eye protection may be an effective measure to prevent SARS-CoV-2 infections. Randomized trials are needed to assess whether the observed associations are caused by protection of the eye or confounding factors such as other systematic differences between users and non-users of eye protection, co-interventions, or changes in COVID-19 incidence when comparisons were done over time. This is a pragmatic, virtual, parallel group, 1:1 randomized, superiority trial. The researchers will recruit and randomize participants via an online portal. The trial will be fully remote and virtual without any personal interaction between investigators and participants. All members of the public are eligible who confirm that they are at least 18 years of age, do not regularly wear glasses, have not contracted COVID-19 since December 15th 2021, and are willing to be randomized to wear, or not wear glasses in public when close to other people, for a 2-week period. Persons who are dependent on visual aids but typically use contact lenses are eligible. The participants will be randomized (1:1) to wear glasses (sunglasses or other types of glasses) in public spaces when close to others (public transport, shopping centers etc.), or to the control group. The control group will be asked not to wear glasses in public spaces when close to others. The primary outcome is positive test for COVID-19. The researchers aim to include about 25,000 participants to have a statistical power of 80% to detect a relative risk reduction of 25% for the primary outcome.

Interventions

BEHAVIORALWearing glasses (any type)

Participants are asked to wear glasses in public spaces.

Sponsors

University of Basel
CollaboratorOTHER
Norwegian Institute of Public Health
Lead SponsorOTHER_GOV

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE

Masking description

No blinding was feasible, except for in the analysis phase. One member of our team (A.H.) provided the chief analyst (I.H.E.) with a data file in which group allocation was blinded. The chief analyst presented the main results to the project team members, who were also blinded to the group allocation (and data on use of glasses). We discussed how we would interpret the findings depending on whether one group or the other was the intervention group, and we prepared a short report that we posted online before unblinding ourselves to the group allocation.

Intervention model description

Sequence generation We will use a simple 1:1 randomization by means of computer-generated random numbers. The allocation will be concealed as the participant themselves will be directly informed of their allocation as soon as they have agreed to take part in the trial and have completed the online consent form. Generation of allocation sequence, enrolment of participants and assignment of participants will all be handled by the digital recruitment platform.

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

* at least 18 years of age * owns or can borrow glasses that can be used (e.g. sun-glasses) * willing to be randomized to wear, or not wear glasses outside the home when close to others, for a 2-week period. * provides informed consent

Exclusion criteria

* does regularly wear glasses (contact lenses are accepted) * contracted COVID-19 after December 15th 2021.

Design outcomes

Primary

MeasureTime frameDescription
Positive test for SARS-CoV-2Days 3 to 17 after start of trial period.The investigators will compare the incidence of notified cases of COVID-19 (i.e. registered positive SARS-CoV-2 tests).

Secondary

MeasureTime frameDescription
Health care use for injuries health care use (all causes) from day 1 to day 21 (data source: KPR and NPRDay 1 to 21Routinely collected data (KPR and NPR databases)
Health care use (all causes)Day 1 to 21Routinely collected data (KPR and NPR databases)
Health care use for respiratory symptomsDay 1 to 28Routinely collected data (Norwegian Registry for Primary Health Care (KPR) and Norwegian Patient Registry (NPR) databases)
Respiratory symptomsDay 1 to 17Self report
Health care use for injuriesDay 1 to 17Self report
Any positive COVID-19 test resultDay 1 to 17Self report

Countries

Norway

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 10, 2026