Scents of Progress: Leveraging a Novel Device for Olfactory Training in Older Adults (SPLENDOR-OA)

April 10, 2026 updated by: Johns Hopkins University

SPLENDOR-OA; Scents of Progress: Leveraging a Novel Device for Olfactory Training in Older Adults

The goal of this clinical trial is to learn if ScentCare, a novel olfactory training device and accompanying companion web-based application, will lead to improved olfactory and well-being outcomes in elderly patients with Olfactory Dysfunction (OD). The main question it aims to answer is:

- What effect does the olfactory training device (ScentCare) and accompanying companion web-based application have on olfaction?

Researchers will compare ScentCare to solving Sudoku puzzles to see the effects of olfactory training using this novel device on olfaction. Previous studies have used Sudoku puzzles when studying the effect of smell training. Since smell training is thought to work by stimulating and engaging higher order cognition, Sudoku is a suitable activity for participants in the control group since it serves as a correlate with similar degree of stimulation.

Participants will:

  • Use ScentCare (intervention) or solve Sudoku puzzles (control) twice daily for 3 months.
  • Visit the clinic twice, once upon enrollment and once three months later.
  • Complete a formal smell test using Sniffin' Sticks smell test at the beginning of the study and again at the end of the study (3 months) during the initial and follow up visit.
  • Complete questionnaires at the beginning of the study and again at the end of the study (3 months) during the initial and follow up visit.

Study Overview

Detailed Description

This research is being done to better understand the efficacy of an investigational device and its companion phone application (together called "ScentCare") in treating olfactory dysfunction.

Although the sense of smell is commonly overlooked, it is a unique and special human sensory function that has implications for quality of life, such as the enjoyment of food and nutrition or the ability to perceive dangers, such as smoke or noxious fumes. Although smell training is a well-established rehabilitation treatment for people with olfactory dysfunction (OD) or loss of smell, no standardized smell training method is currently available. Thus, the investigators invented a device and companion phone app that standardizes and compiles smell training. The investigators are seeking data on how to improve the device and its efficacy in general.

This study will have participants complete formal smell testing prior to using the ScentCare or Sudoku daily for three months and after the completion of the intervention. Participants will also answer a survey (questionnaires asked will include olfactory specific qualify of life assessment, cognitive assessment, depression assessment, anxiety assessment, device use and compliance) upon enrollment and after completion of the intervention (3 months follow up).

Once enrolled, participants will be randomized to either the "experimental" or "control" group. Participants in the experimental group will be given an olfactory training device and instructions for the smartphone-based olfactory training application. This olfactory training device consists of a hand-held rotating wheel with 8 individual scent chambers allowing personalized exposure to odorants (smells) according to the training app's instructions. If the participant does not have a smartphone, the participant will be given a training booklet with corresponding cues and instructions. Twice daily, 5-minute training sessions will be completed for 3 months. Participants in the control group will not undergo olfactory training but will be asked to complete sudoku puzzles for the same duration as the training for the experimental group.

After three months of either smell training with ScentCare or completing Sudoku puzzles, participants will be re-evaluated using the Sniffin' Sticks test and the same surveys to assess the impact of the intervention. Results will be compared between the two groups. Additionally, participants in the ScentCare group will provide feedback on the device's feasibility, ease of use, and overall effectiveness to inform its potential for broader application.

Study Type

Interventional

Enrollment (Estimated)

60

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

  • Name: Wassim Najjar, M.D.
  • Phone Number: 443-997-6467
  • Email: wnajjar1@jh.edu

Study Locations

    • Maryland
      • Baltimore, Maryland, United States, 21287
        • Recruiting
        • Johns Hopkins Outpatient Center, Department of Otolaryngology - Head and Neck Surgery
        • Contact:
        • Principal Investigator:
          • Nicholas Rowan, M.D.

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Adults 60 years of age or older.
  • English-speaking patients.
  • Patients with a diminished or lost sense of smell.
  • Patients who have not done smell training before

Exclusion Criteria:

  • Patients who are sensitive to any of the scents used in the study.
  • Patients with a diagnosis of congenital anosmia.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Olfactory Training
Participants will receive the ScentCare olfactory training device, which includes eight encapsulated scents: Eucalyptus, Cinnamon, Lemon, Coffee, Campfire, Cherry, Vanilla, and Lavender. To guide the participant in using the device, participants will have access to either a web-based application or a booklet, depending on the participant's preference. These resources will provide instructions on how to perform the smell training effectively. The training will be conducted twice daily over a period of three months.
ScentCare is a smell training device with eight encapsulated scents housed in separate compartments and is contained using a charcoal filter, which will be dispersed in the base of our device to prevent smell contamination in the user's environment. The outer casing contains an opening that can be manually rotated to line up with the casing on each scent. This is facilitated by a rod in the center of the device, which serves as the axis of rotation. By pressing the capsule, the desired scent is released through a hole in the casing, similar to the mechanism of a pen. The user presses the compartment back downwards into the casing when done. The ScentCare mobile application offers clear instructions for at-home smell training and testing, with features like scent randomization to prevent users from getting accustomed to a specific order. It provides detailed guidance on device use and allows users to schedule sessions and receive daily reminders, ensuring a structured training regimen.
Other: Control Arm (Sudoku Puzzles)
Participants will be asked to complete sudoku puzzles twice daily over a period of three months.
Sudoku puzzles of consistent and regular difficulty

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in olfaction as assessed by Sniffin' Sticks olfactory testing kit
Time Frame: Baseline and 3 months
Changes in olfaction between the two groups will be assessed using Sniffin' Sticks olfactory testing. The main outcome is a cumulative Threshold, Discrimination, and Identification (TDI) score, where a TDI score above 30.5 is considered normal, between 30.5 and 16 indicates hyposmia (reduced smell), and below 16 signifies anosmia (complete loss of smell).
Baseline and 3 months

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in peripheral olfaction as assessed by Sniffin' Sticks olfactory testing kit
Time Frame: Baseline and 3 months
Changes in peripheral olfaction between the two groups will be assessed using Sniffin' Sticks. Sniffin's Sticks tests olfactory function in three domains: threshold, discrimination, and identification. Threshold testing allows for peripheral olfaction testing. The most dilute concentration of odorant that the participant is able to reliably detect is determined. Score ranges between 1 and 16, with higher score indicating better peripheral olfaction.
Baseline and 3 months
Change in central olfaction as assessed by Sniffin' Sticks olfactory testing kit
Time Frame: Baseline and 3 months

Changes in central olfaction between the two groups will be assessed using Sniffin' Sticks. Sniffin's Sticks tests olfactory function in three domains: threshold, discrimination, and identification. The discrimination and identification tests allow for central olfaction testing. In discrimination testing, the participant is evaluated on their ability to discern the unique scent among three scented sticks. In identification testing, the patient names the smell using a multiple choice form which offers four options for every scented stick, only one of which is correct.

Both tests have scores ranging between 0 and 16, with higher scores indicating better central olfaction.

Baseline and 3 months
Change in olfactory specific Quality of Life as Assessed by the Questionnaire of Olfactory Disorders-Negative Statements (QOD-NS)
Time Frame: Baseline and 3 months
Changes in overall olfactory wellbeing between the two groups will be assessed using Quality of life (QoL) assessment (Questionnaire of Olfactory Disorders-Negative Statements (QOD-NS). This instrument consists of 17 negative statements graded from 0 to 3 for a maximum score range of 0-51 (higher scores reflect worse QOL). The QOD-NS has 4 distinct factor domains, broadly categorized as those that relate to eating, anxiety, social interactions, and annoyance.
Baseline and 3 months
Change in overall cognition as assessed by the Montreal Cognitive Assessment (MoCA) test
Time Frame: Baseline and 3 months

Changes in overall cognition will be assessed between the two groups using Montreal Cognitive Assessment (MoCA) test which is a rapid screening instrument for mild cognitive dysfunction. It assesses different cognitive domains: attention and concentration, executive functions, memory, language, visuoconstructional skills, conceptual thinking, calculations, and orientation. This test involves memorizing a short list of words, naming objects shown in pictures, copying shapes and performing other tasks. The test is scored out of a maximum of 30 points, and the results are interpreted as follows:

26 or higher: Normal cognitive health; 18-25: Mild cognitive impairment (MCI); 10-17: Moderate cognitive impairment; Less than 10: Severe cognitive impairment

Baseline and 3 months
Change in overall anxiety as assessed by the General Anxiety Disorder Questionnaire-7 (GAD-7)
Time Frame: Baseline and 3 months
Changes in overall anxiety will done using the Generalized Anxiety Disorder Questionnaire-7 (GAD-7). The GAD-7 consists of 7 items (scored 0-21) to assess anxiety symptoms over the previous 2 weeks. Higher scores indicate higher frequency of symptoms. Scores greater than or equal to 10 are indicative of generalized anxiety disorder.
Baseline and 3 months
Change in overall depression as assessed by the Patient Health Questionnaire-8 (PHQ-8)
Time Frame: Baseline and 3 months
Changes in overall depression will be assessed using the Patient Health Questionaire-8 (PHQ-8). This consists of a 2-item screen (scored 0-6) from PHQ-2, with a score above 2 prompting PHQ-8. The PHQ-8 consists of 8 items (scored 0-24) to assess depressive symptoms over the previous 2 weeks. Higher scores indicate higher frequency of symptoms, and a score greater than or equal to 10 is indicative of major depression.
Baseline and 3 months
Compliance as assessed by the number of patients who consistently used the olfactory training device or solved the Sudoku puzzles
Time Frame: 3 months post intervention
Patient compliance will be tracked for both groups over the three-month period. Sudoku users will log the number of puzzles completed daily and the time spent on each, while ScentCare users will rely on the companion app to monitor the frequency of their smell training sessions. Compliance data from both methods will be compared after the trial.
3 months post intervention
Device usability as assessed by the System Usability Scale (SUS)
Time Frame: 3 months post intervention
Device usability will be evaluated using the System Usability Scale (SUS), a validated 10-item questionnaire. Participants will rate each statement on a scale from 1 (strongly disagree) to 5 (strongly agree). Score range 10-50. Usability scores will be calculated based on SUS guidelines to assess ScentCare's usability and identify areas for improvement.
3 months post intervention

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Nicholas Rowan, M.D., Johns Hopkins University, Department of Otolaryngology - Head and Neck Surgery

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

April 15, 2025

Primary Completion (Estimated)

December 31, 2026

Study Completion (Estimated)

March 31, 2027

Study Registration Dates

First Submitted

December 10, 2024

First Submitted That Met QC Criteria

December 10, 2024

First Posted (Actual)

December 13, 2024

Study Record Updates

Last Update Posted (Actual)

April 13, 2026

Last Update Submitted That Met QC Criteria

April 10, 2026

Last Verified

April 1, 2026

More Information

Terms related to this study

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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