Physical distancing during choir singing rehearsals and risk of respiratory tract infections: study protocol for a pilot study
| ISRCTN | ISRCTN80062362 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN80062362 |
| ClinicalTrials.gov (NCT) | Nil known |
| Clinical Trials Information System (CTIS) | Nil known |
| Protocol serial number | REK938874 |
| Sponsor | Norwegian Institute of Public Health |
| Funder | Norwegian Institute of Public Health |
- Submission date
- 04/11/2025
- Registration date
- 05/11/2025
- Last edited
- 19/11/2025
- Recruitment status
- Not yet recruiting
- Overall study status
- Ongoing
- Condition category
- Infections and Infestations
Plain English summary of protocol
Background and study aims
During the COVID-19 pandemic, the authorities advised that people should keep distance between one another. They broadly advised physical distancing, such as keeping 1-2 meters away from one another in general, and also implemented more specific guidelines and mandates such as increased distance during physical exercise, singing or other activities that could increase the risk of transmission. Collectively, such preventative measures contributed to decreased transmission during the pandemic, but there is still uncertainty around the effects of the individual measures. We need more knowledge on the effect of individual measures to be prepared for future pandemics. Increased knowledge of the effect of physical distancing may contribute to the continuation of social activities such as choir practices in a safe manner during future pandemics. We therefore aim to investigate whether physical distancing during choir practices can reduce the risk for respiratory tract infections. In preparation for the main study, we are planning a test project (pilot study), to assess whether a larger study is feasible.
Who can participate?
For this study, choirs with at least 15 adult members who rehearse at least weekly are eligible to participate. In addition, we will recruit adults who don’t participate in organized choir singing as a reference from the greater Oslo area through the FHI-panel.
We plan to recruit about 10 choirs, who will be randomly divided into two groups:
1. Distancing group: Choirs in this group will be advised to keep 1.5 meters distance from each other during the choir practice, starting from when they enter the venue and up until the choir practice is finished.
2. Control group: Choirs in this group will conduct their practice as usual.
What does the study involve?
The study period lasts for 9 weeks and consists of the following:
- The choir will practice with or without instructions on distancing during the first 8 weeks of the study period.
- You will be asked to fill out a questionnaire ahead of the study period, every week of the study period and after the study period. Each questionnaire takes less than 10 minutes.
- In the questionnaire we collect data on:
o Symptoms of common cold or other respiratory infections
o Vaccinations against COVID-19 and influenza
o Whether or not you belong in a risk group for developing severe disease during respiratory tract infections
o Participation in choir practices and if you have followed recommendations for distancing
In addition, we ask that you take rapid tests every week to see if you have been infected with COVID-19, influenza or RSV during the study.
After the study period is over, the participants will be asked to evaluate their experience of being involved with the study. A subset of participants will also be invited to focus group interviews to give feedback on their experiences so that we can improve the future main study.
We will not be collecting information from registers or other sources, we rely on information the participants submit in the questionnaires themselves.
What are the possible benefits and risks of participating?
The study entails no increased health risks for the participants compared to their normal activity. The choir will receive NOK 4000,- in support for funding as compensation.
Where is the study run from?
The study is run from Centre for Epidemic Interventions Research, at the Norwegian Institute of Public Health, Oslo, Norway.
When is the study starting and how long is it expected to run for?
The study will start in February 2026 and run for a total of nine weeks.
Who is funding the study?
No sponsors are involved in the study, the study is funded by intramural funding at the Norwegian Institute of Public Health.
Who is the main contact?
Project leader Erle Refsum is the main contact: erle.refsum@fhi.no
Contact information
Public, Scientific, Principal investigator
Folkehelseinstituttet, Postboks 222 Skøyen
Oslo
0213
Norway
 ORCID ID |
0000-0002-9591-5152 |
|---|---|
| Phone | +47 99314576 |
| erle.refsum@fhi.no |
Study information
| Primary study design | Interventional |
|---|---|
| Study design | Pragmatic two-arm parallel group cluster-randomized trial |
| Secondary study design | Cluster randomised trial |
| Scientific title | Effect of physical distancing during vocal ensemble (choir) rehearsals: protocol for a pilot cluster-randomized controlled trial to investigate feasibility, acceptability, adherence, and outcome distribution |
| Study acronym | DISCHO |
| Study objectives | The primary aim is to evaluate feasibility and acceptability of a planned randomized trial on the effects of physical distancing recommendations during vocal ensembles (choir) rehearsals. We will also investigate adherence to the intervention and characterize a candidate outcome variable to facilitate power analysis for the planned main trial. |
| Ethics approval(s) |
Approved 17/10/2025, Regional committees for medical and health research ethics (REC) South-East Norway (REK Sør-Øst, Postboks 1130, Blindern, Oslo, 0318, Norway; +47 228 51 001; rek-sorost@medisin.uio.no), ref: 938874 |
| Health condition(s) or problem(s) studied | Respiratory tract infections in healthy adults |
| Intervention | This study aims to assess the effectiveness of maintaining physical distance from others in real-life situations. During the intervention, choir participants will be instructed to avoid close contact (closer than 1.5 meter) with other participants who are not family members during choir rehearsals the entire time while inside the rehearsal venue. The intervention period will last for eight weeks. In the control arm, participants will conduct choir rehearsals under standard conditions without any distancing restrictions while they are in the venue. The comparator is chosen to represent the risk of respiratory tract infection during choir singing without any physical distancing measures. To compare the time to developing an respiratory tract infection among persons participating in vocal ensembles to persons not participating in organized singing, an external reference group, with a similar geographical location as the choirs in the control group will be recruited. The external reference group will not receive any restrictions on physical distancing. The choirs will be randomly allocated 1:1 to the intervention and control arms for a study period of 2 months. |
| Intervention type | Behavioural |
| Primary outcome measure(s) |
1. Time to respiratory tract infection (RTI) is measured using a composite of self-reported symptoms via weekly individual questionnaires and positive antigen test results for SARS-CoV-2, influenza A/B, or RSV from study start to last completed questionnaire or end of study period |
| Key secondary outcome measure(s) |
1. Time to first positive test for SARS-CoV-2, influenza A/B, or RSV is measured using antigen testing |
| Completion date | 01/04/2026 |
Eligibility
| Participant type(s) | Other |
|---|---|
| Age group | Mixed |
| Lower age limit | 18 Years |
| Upper age limit | 100 Years |
| Sex | All |
| Target sample size at registration | 450 |
| Key inclusion criteria | Inclusion criteria for choirs are: 1. The choir comprises at least ≥ 15 members 2. The choir rehearses at least ≥ once a week 3. The majority of the choir members consent to participate in the study and follow the assigned intervention 4. The choir may hold rehearsals in a venue that allow for at least 1.5 meter distance between singers during the study period Inclusion criteria for choir members are: 5. Aged 18 years or older at the day of signing consent 6. Provide informed consent to participate in the study and contribute weekly data Inclusion criteria for choir members for a substudy on adherence to the intervention are (only including a few choirs in the intervention arm): 7. Each choir members are willing to have an assigned place for the duration of each practice, and share information on their location, and 8. All choir members provide consent to be filmed or monitored during rehearsals Inclusion criteria for the reference group participants are: 9. Member of the Norwegian Institute of Public Health survey panel (“FHI-panel”) 10. Resident of the greater Oslo region, Norway 11. Provides informed consent to participate in the study and contribute weekly data |
| Key exclusion criteria | Exclusion criterion for the reference group participants is 1. Regularly attends choir rehearsals |
| Date of first enrolment | 01/12/2025 |
| Date of final enrolment | 01/01/2026 |
Locations
Countries of recruitment
- Norway
Study participating centre
Oslo
0213
Norway
Results and Publications
| Individual participant data (IPD) Intention to share | Yes |
|---|---|
| IPD sharing plan summary | Stored in publicly available repository |
| IPD sharing plan | Code for data preparation and statistical analysis will be made public (e.g., via GitHub and Zenodo), along with an anonymized version of the final data set used for analysis. |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Protocol file | version 2.0 | 11/10/2025 | 17/11/2025 | No | No |
| Protocol file | version 2 | 19/11/2025 | 19/11/2025 | No | No |
| Study website | Study website | 11/11/2025 | 11/11/2025 | No | Yes |
Additional files
Editorial Notes
19/11/2025: Uploaded protocol v2 (not peer-reviewed) as an additional file.
17/11/2025: Uploaded protocol (not peer-reviewed) as an additional file.
04/11/2025: Trial's existence confirmed by Regional committees for medical and health research ethics (REC) South-East Norway.
