Finding Out if COVID-19 Infection Can be pREdicted by ChAnges in Smell and/or Taste (FORECAST)
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ClinicalTrials.gov Identifier: NCT04377815 |
Recruitment Status :
Completed
First Posted : May 6, 2020
Last Update Posted : January 19, 2021
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Condition or disease | Intervention/treatment |
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COVID-19 Anosmia | Other: General Public cohort |
The FORECAST Study is an observational cohort study looking at two cohorts of patients presenting with COVID-19: a general public cohort, aiming to investigate if new loss or reduced sense of smell and/or taste are early signs of COVID-19 and a hospital cohort, which will investigate if taste/smell changes can predict the clinical course of a COVID-19 infection.
The main of objective of this study is to investigate whether loss/or reduced sense of smell and/or taste in the absence of fever and/or persistent cough are indicative of Coronavirus Infectious disease 2019 (COVID-19) infection. In addition, the study aims to investigate whether loss/or reduced sense of smell and/or taste precede the development of fever and persistent cough in people with COVID-19 infection and also whether loss of/reduced sense of smell and/or taste changes can be used to predict the clinical course of the disease.
General public FORECAST: Participants over the age of 18 will be sent a text message invite through participating GP practices' patient messaging systems. This will direct participants to a website (hosted by Dendrite Clinical Systems) where study subjects will find the participant information sheet, screening checks and consent form. Enrolled participants will complete an online questionnaire containing questions about smell and taste changes, as well as other symptoms of COVID-19. Participants will then be sent a near-patient rapid antibody test kit for COVID-19 to be undertaken only under medical supervision. Participants will be booked for a video conference appointment with either a doctor or nurse and the screening test will be performed under medical supervision. The outcome of the test will be documented, discussed with the patient and appropriate advice given. Four weeks after completing the first questionnaire participant will be sent an email and / or text message asking them to complete a second questionnaire.
This second questionnaire will contain questions about resolution of smell/taste symptoms and other symptoms of COVID-19. In case COVID-19 positive patients are subsequently admitted to hospital as a result of COVID-19, consent will be obtained to collect information on the outcome of the admission from discharge letter via GP. The data obtained will be analysed to determine if smell/taste symptoms alone are indicative of COVID-19 infection, whether smell/taste symptoms are early symptoms fo COVID-19 infection and whether smell/taste changes can be used to predict the clinical course of COVID-19 disease.
Hospital FORECAST: clinical records of patients admitted to University College London Hospital (UCLH) and the Whittington Hospital as a result of COVID-19 will be reviewed. The clinical notes of COVID-19 positive patients where absence or presence of smell/taste changes have been documented will be selected for review. Anonymised clinical data will be collected about symptoms on admission, the course of illness and outcomes. The study primary outcome will be to compare case fatility rate in COVID-19 postivite with documented history of loss/reduced sense of smell and/or taste compared to COVID-19 postive with documented history of no loss/reduced sense of smell and/or taste. The study will investigate whether loss/reduced sense of smell and/or taste can predict the course of illness and outcomes in COVID-19.
Study Type : | Observational |
Actual Enrollment : | 569 participants |
Observational Model: | Cohort |
Time Perspective: | Other |
Official Title: | FORECAST Study: Finding Out if COVID-19 Infection Can be pREdicted by ChAnges in Smell and/or Taste |
Actual Study Start Date : | April 23, 2020 |
Actual Primary Completion Date : | May 14, 2020 |
Actual Study Completion Date : | June 24, 2020 |

Group/Cohort | Intervention/treatment |
---|---|
General Public cohort
General Public
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Other: General Public cohort
No intervention is being tested
Other Name: Hospital cohort |
Hospital cohort
Medical records of patients hospitalised due to COVID-19
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- Percentage of people reporting changes in smell/taste [ Time Frame: 4 weeks ]percentage of people who report loss/reduced sense of smell or taste
- mortality rate [ Time Frame: through study completion, an average of 1 year ]to compare the case mortality rate in COVID-19 patients who experienced smell/taste changes compared to mortality in those who did not experience smell/taste changes.
- Percentage of people with change in smell/taste before other symptoms [ Time Frame: 4 weeks ]To identify the percentage of people who report changes in taste and/or smell before developing either fever or persistent cough who are positive for SARS-CoV-2 IgM and IgG
- proportion of other COVID-19 linked symptoms in people with smell and/or taste change [ Time Frame: 4 weeks ]To examine the proportion of other COVID-19 linked symptoms in people with smell and/or taste change who are positive positive for SARS-CoV-2 IgM and IgG who never develop fever and/or cough.
- Percentage of people with persistent changes in smell and/or taste [ Time Frame: 12 weeks ]To determine the percentage of people whose smell and/or taste symptoms persist for greater than 4 weeks in people who are positive for SARS-CoV-2 IgM and IgG
- Percentage of hospitalisation [ Time Frame: 12 weeks ]To determine the percentage of patients who report loss/decrease in sense of smell and/or taste changes before or in the absence of other symptoms of COVID-19, who are admitted to hospital with COVID-19
- co-morbidities association [ Time Frame: through study completion, an average of 1 year ]To investigate whether loss/reduced sense of smell and/or taste are associated with the course of illness and outcomes in COVID-19
- prevalence of changes in smell/taste [ Time Frame: through study completion, an average of 1 year ]Assessing the prevalence of previous loss/decrease in sense of smell and/or taste changes in patients admitted to secondary care with COVID-19 infection.
- clinical outcomes [ Time Frame: through study completion, an average of 1 year ]Correlating the presence of loss/decrease in sense of smell and/or taste changes to clinical outcomes including case fatality rate.

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | Yes |
Sampling Method: | Probability Sample |
General public FORECAST cohort
Participating GP practices will send out text messages to potentially eligible patients registered with the practice inviting those who have noticed a recent (within the past 4 weeks) change (loss/decrease) in their sense of smell and/or taste to take part in a research study related to COVID-19 infection.
Hospital FORECAST cohort
For Hospital FORECAST, patients admitted with COVID-19 to UCLH and The Whittington Hospital will be identified through clinical coding. Their records will be reviewed by an appropriately qualified healthcare professional against the study's inclusion/exclusion criteria.
General public FORECAST cohort: Participants will confirm their eligibility on the online form by confirming they meet the following inclusion and exclusion criteria:
Inclusion Criteria:
- Age over 18 years;
- Able to read and write English;
- Access to a computer or smartphone with internet access and ability to access video calling;
- Willingness to undertake a COVID-19 screening test;
- Willingness for their GP to be informed of their participation in the study.
Exclusion Criteria:
- Pre-existing smell or taste impairment of longer than 6 weeks duration;
- People lacking capacity.
Hospital FORECAST cohort: The patient records to be included in this part of the study will be selected by a healthcare professional based on the following inclusion and exclusion criteria
Inclusion Criteria:
- Admitted to hospital due to COVID-19 and documentation of either presense or absence of loss/reduced sense of smell and/or taste.
Exclusion Criteria:
- Changes in smell and/or taste either present or absent not documented.
- Admission due to other reason with later diagnosis of COVID-19 as an inpatient.
- Incomplete medical records.
- Patients with longstanding pre-existing smell and/or taste impairment.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04377815
United Kingdom | |
University College London Hospital | |
London, United Kingdom, WC1E 6JF | |
GP Practices | |
London, United Kingdom |
Responsible Party: | University College, London |
ClinicalTrials.gov Identifier: | NCT04377815 |
Other Study ID Numbers: |
132311 20/HRA/1879 ( Other Identifier: Queen Square REC ) |
First Posted: | May 6, 2020 Key Record Dates |
Last Update Posted: | January 19, 2021 |
Last Verified: | January 2021 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | Undecided |
Studies a U.S. FDA-regulated Drug Product: | No |
Studies a U.S. FDA-regulated Device Product: | No |
COVID-19 anosmia taste |
COVID-19 Anosmia Infections Respiratory Tract Infections Pneumonia, Viral Pneumonia Virus Diseases Coronavirus Infections Coronaviridae Infections |
Nidovirales Infections RNA Virus Infections Lung Diseases Respiratory Tract Diseases Olfaction Disorders Sensation Disorders Neurologic Manifestations Nervous System Diseases |