Trial Outcomes & Findings for Effects of Open-label Placebos on COVID-related Psychological Health (NCT NCT05035550)

Last Updated: 2024-03-13

Results Overview

Self-reported COVID-19 related stress was measured using the COVID-19 Stress Scale. The Covid stress scale (CSS) is a 36-item self-report questionnaire that measures stress-related to COVID-19 (Taylor et al., 2020). Participants rated each item on a 0 (not at all) to 4 (extremely) scale. For the purposes of this study, only total scores were calculated. Total score ranges from 0-144 with higher scores indicating greater COVID-related stress.

Recruitment status

COMPLETED

Study phase

Target enrollment

64 participants

Primary outcome timeframe

COVID-19 related stress was measured at Baseline (Day 1), Midpoint (Day 7), and Endpoint (Day 14)

Results posted on

2024-03-13

Participant Flow

Participant milestones

Participant milestones
Measure	Non-Deceptive Placebo The NDP group was informed that the purpose of the study was to test a mind-body intervention that might help participants deal with the stress and anxiety that they are feeling during the pandemic. The intervention included two videos that introduced the effects of non-deceptive placebos, followed by a presentation on up-to-date non-deceptive placebo research. The participants then received instruction on how they would take their non-deceptive placebos for the next two weeks. Participants were asked to complete daily pill-taking adherence surveys (\~5 min) and weekly at midpoint (1-week) and endpoint (2-week). Non-Deceptive Placebo: The placebos were ordered through Amazon from Zeebo® (Zeebo, Zeebo Effect, LLC, South Burlington, Vermont, USA). The placebos in this study were blue and white capsules containing Microcrystalline cellulose (an inert fiber). Ingredients include ones that are typically used to make pills including silica, gelatin, titanium dioxide, red #3 food coloring, and blue #1 food coloring. Placebo capsules were free of any active ingredients. These bottles were not branded specifically for the experiment, including the brand name ("Zeebo Relief"), description of the contents, directions, and a disclaimer. The investigators chose to not include a custom label for transparency and in order to increase "non-deceptive" placebo effects. Participants were instructed to take two pills a day, one in the morning and one in the evening.	No-Treatment Control The Control group did not receive an intervention. Instead, participants were informed that the purpose of the study was to track individual psychological and physical health over longer time periods in the context of the pandemic. Participants were asked to complete weekly questionnaires at midpoint (1-week) and endpoint (2-week).
Overall Study STARTED	32	32
Overall Study COMPLETED	29	32
Overall Study NOT COMPLETED	3	0

Reasons for withdrawal

Reasons for withdrawal
Measure	Non-Deceptive Placebo The NDP group was informed that the purpose of the study was to test a mind-body intervention that might help participants deal with the stress and anxiety that they are feeling during the pandemic. The intervention included two videos that introduced the effects of non-deceptive placebos, followed by a presentation on up-to-date non-deceptive placebo research. The participants then received instruction on how they would take their non-deceptive placebos for the next two weeks. Participants were asked to complete daily pill-taking adherence surveys (\~5 min) and weekly at midpoint (1-week) and endpoint (2-week). Non-Deceptive Placebo: The placebos were ordered through Amazon from Zeebo® (Zeebo, Zeebo Effect, LLC, South Burlington, Vermont, USA). The placebos in this study were blue and white capsules containing Microcrystalline cellulose (an inert fiber). Ingredients include ones that are typically used to make pills including silica, gelatin, titanium dioxide, red #3 food coloring, and blue #1 food coloring. Placebo capsules were free of any active ingredients. These bottles were not branded specifically for the experiment, including the brand name ("Zeebo Relief"), description of the contents, directions, and a disclaimer. The investigators chose to not include a custom label for transparency and in order to increase "non-deceptive" placebo effects. Participants were instructed to take two pills a day, one in the morning and one in the evening.	No-Treatment Control The Control group did not receive an intervention. Instead, participants were informed that the purpose of the study was to track individual psychological and physical health over longer time periods in the context of the pandemic. Participants were asked to complete weekly questionnaires at midpoint (1-week) and endpoint (2-week).
Overall Study Withdrawal by Subject	3	0

Baseline Characteristics

Two participants in the non-deceptive placebo group dropped out before baseline assessment.

Baseline characteristics by cohort

PRIMARY outcome

Timeframe: COVID-19 related stress was measured at Baseline (Day 1), Midpoint (Day 7), and Endpoint (Day 14)

Outcome measures

Outcome measures
Measure	Non-Deceptive Placebo n=29 Participants The NDP group was informed that the purpose of the study was to test a mind-body intervention that might help participants deal with the stress and anxiety that they are feeling during the pandemic. The intervention included two videos that introduced the effects of non-deceptive placebos, followed by a presentation on up-to-date non-deceptive placebo research. The participants then received instruction on how they would take their non-deceptive placebos for the next two weeks. Participants were asked to complete daily pill-taking adherence surveys (\~5 min) and weekly at midpoint (1-week) and endpoint (2-week). Non-Deceptive Placebo: The placebos were ordered through Amazon from Zeebo® (Zeebo, Zeebo Effect, LLC, South Burlington, Vermont, USA). The placebos in this study were blue and white capsules containing Microcrystalline cellulose (an inert fiber). Ingredients include ones that are typically used to make pills including silica, gelatin, titanium dioxide, red #3 food coloring, and blue #1 food coloring. Placebo capsules were free of any active ingredients. These bottles were not branded specifically for the experiment, including the brand name ("Zeebo Relief"), description of the contents, directions, and a disclaimer. The investigators chose to not include a custom label for transparency and in order to increase "non-deceptive" placebo effects. Participants were instructed to take two pills a day, one in the morning and one in the evening.	No-Treatment Control n=32 Participants The Control group did not receive an intervention. Instead, participants were informed that the purpose of the study was to track individual psychological and physical health over longer time periods in the context of the pandemic. Participants were asked to complete weekly questionnaires at midpoint (1-week) and endpoint (2-week).
COVID-19 Related Stress Baseline (Day 1)	34.93 score on a scale Standard Deviation 18.78	35.13 score on a scale Standard Deviation 20.50
COVID-19 Related Stress Midpoint (Day 7)	26.24 score on a scale Standard Deviation 17.29	32.37 score on a scale Standard Deviation 18.51
COVID-19 Related Stress Endpoint (Day 14)	12.28 score on a scale Standard Deviation 16.01	28.34 score on a scale Standard Deviation 20.61

PRIMARY outcome

Timeframe: Perceived stress measured at Baseline (Day 1), Midpoint (Day 7), and Endpoint (Day 14)

Self-reported perceived stress was measured using the Perceived Stress Scale (PSS). The Perceived Stress Scale (PSS) is a 10-item self-report questionnaire that assesses the extent to which different situations affect our perceptions of stress during the last month (Cohen, 1994). The scale was modified for the current study in order to measure ratings of perceived stress over the past 7 days. Participants rated each item on a 0 (never) to 4 (very often) scale. Total score ranges from 0-40 with higher scores indicating greater perceived stress.

Outcome measures

Outcome measures
Measure	Non-Deceptive Placebo n=29 Participants The NDP group was informed that the purpose of the study was to test a mind-body intervention that might help participants deal with the stress and anxiety that they are feeling during the pandemic. The intervention included two videos that introduced the effects of non-deceptive placebos, followed by a presentation on up-to-date non-deceptive placebo research. The participants then received instruction on how they would take their non-deceptive placebos for the next two weeks. Participants were asked to complete daily pill-taking adherence surveys (\~5 min) and weekly at midpoint (1-week) and endpoint (2-week). Non-Deceptive Placebo: The placebos were ordered through Amazon from Zeebo® (Zeebo, Zeebo Effect, LLC, South Burlington, Vermont, USA). The placebos in this study were blue and white capsules containing Microcrystalline cellulose (an inert fiber). Ingredients include ones that are typically used to make pills including silica, gelatin, titanium dioxide, red #3 food coloring, and blue #1 food coloring. Placebo capsules were free of any active ingredients. These bottles were not branded specifically for the experiment, including the brand name ("Zeebo Relief"), description of the contents, directions, and a disclaimer. The investigators chose to not include a custom label for transparency and in order to increase "non-deceptive" placebo effects. Participants were instructed to take two pills a day, one in the morning and one in the evening.	No-Treatment Control n=32 Participants The Control group did not receive an intervention. Instead, participants were informed that the purpose of the study was to track individual psychological and physical health over longer time periods in the context of the pandemic. Participants were asked to complete weekly questionnaires at midpoint (1-week) and endpoint (2-week).
Perceived Stress Baseline (Day 1)	22.52 score on a scale Standard Deviation 6.74	20.34 score on a scale Standard Deviation 7.49
Perceived Stress Midpoint (Day 7)	17.24 score on a scale Standard Deviation 7.19	17.98 score on a scale Standard Deviation 7.12
Perceived Stress Endpoint (Day 14)	15.00 score on a scale Standard Deviation 5.91	17.78 score on a scale Standard Deviation 7.12

PRIMARY outcome

Timeframe: Anxiety symptom severity was measured at Baseline (Day 1), Midpoint (Day 7), and Endpoint (Day 14)

Self-reported anxiety was measured using the PROMIS Emotional Distress - Anxiety - Short Form. The PROMIS Emotional Distress - Anxiety - Short Form is an 8-item self-report questionnaire that assesses anxiety over the past 7 days in adults. Participants rated each item on a 1 (never) to 4 (always) scale. Total score ranges from 8-40 with higher scores indicating greater anxiety.

Outcome measures

Outcome measures
Measure	Non-Deceptive Placebo n=29 Participants The NDP group was informed that the purpose of the study was to test a mind-body intervention that might help participants deal with the stress and anxiety that they are feeling during the pandemic. The intervention included two videos that introduced the effects of non-deceptive placebos, followed by a presentation on up-to-date non-deceptive placebo research. The participants then received instruction on how they would take their non-deceptive placebos for the next two weeks. Participants were asked to complete daily pill-taking adherence surveys (\~5 min) and weekly at midpoint (1-week) and endpoint (2-week). Non-Deceptive Placebo: The placebos were ordered through Amazon from Zeebo® (Zeebo, Zeebo Effect, LLC, South Burlington, Vermont, USA). The placebos in this study were blue and white capsules containing Microcrystalline cellulose (an inert fiber). Ingredients include ones that are typically used to make pills including silica, gelatin, titanium dioxide, red #3 food coloring, and blue #1 food coloring. Placebo capsules were free of any active ingredients. These bottles were not branded specifically for the experiment, including the brand name ("Zeebo Relief"), description of the contents, directions, and a disclaimer. The investigators chose to not include a custom label for transparency and in order to increase "non-deceptive" placebo effects. Participants were instructed to take two pills a day, one in the morning and one in the evening.	No-Treatment Control n=32 Participants The Control group did not receive an intervention. Instead, participants were informed that the purpose of the study was to track individual psychological and physical health over longer time periods in the context of the pandemic. Participants were asked to complete weekly questionnaires at midpoint (1-week) and endpoint (2-week).
Anxiety Baseline (Day 1)	25.62 score on a scale Standard Deviation 6.76	23.69 score on a scale Standard Deviation 6.62
Anxiety Midpoint (Day 7)	22.07 score on a scale Standard Deviation 7.93	22.19 score on a scale Standard Deviation 7.46
Anxiety Endpoint (Day 14)	19.00 score on a scale Standard Deviation 6.02	21.81 score on a scale Standard Deviation 7.92

PRIMARY outcome

Timeframe: Depression symptom severity was measured at Baseline (Day 1), Midpoint (Day 7), and Endpoint (Day 14)

Self-reported anxiety was measured using the Center for Epidemiological Studies - Depression (CES-D) Scale. The Center for Epidemiological Studies - Depression (CES-D) Scale is a 20-item self-report questionnaire that assesses depressive symptoms over the past 7 days. Participants rated each item on a 0 \[rarely or none at the time (less than one day)\] to 3 \[most or all of the time (5 to 7 days)\] scale. Total score ranges from 0-60 with higher scores indicating higher levels of depression.

Outcome measures

Outcome measures
Measure	Non-Deceptive Placebo n=29 Participants The NDP group was informed that the purpose of the study was to test a mind-body intervention that might help participants deal with the stress and anxiety that they are feeling during the pandemic. The intervention included two videos that introduced the effects of non-deceptive placebos, followed by a presentation on up-to-date non-deceptive placebo research. The participants then received instruction on how they would take their non-deceptive placebos for the next two weeks. Participants were asked to complete daily pill-taking adherence surveys (\~5 min) and weekly at midpoint (1-week) and endpoint (2-week). Non-Deceptive Placebo: The placebos were ordered through Amazon from Zeebo® (Zeebo, Zeebo Effect, LLC, South Burlington, Vermont, USA). The placebos in this study were blue and white capsules containing Microcrystalline cellulose (an inert fiber). Ingredients include ones that are typically used to make pills including silica, gelatin, titanium dioxide, red #3 food coloring, and blue #1 food coloring. Placebo capsules were free of any active ingredients. These bottles were not branded specifically for the experiment, including the brand name ("Zeebo Relief"), description of the contents, directions, and a disclaimer. The investigators chose to not include a custom label for transparency and in order to increase "non-deceptive" placebo effects. Participants were instructed to take two pills a day, one in the morning and one in the evening.	No-Treatment Control n=32 Participants The Control group did not receive an intervention. Instead, participants were informed that the purpose of the study was to track individual psychological and physical health over longer time periods in the context of the pandemic. Participants were asked to complete weekly questionnaires at midpoint (1-week) and endpoint (2-week).
Depression Baseline (Day 1)	22.69 score on a scale Standard Deviation 10.83	20.75 score on a scale Standard Deviation 12.10
Depression Midpoint (Day 7)	17.90 score on a scale Standard Deviation 10.26	20.76 score on a scale Standard Deviation 12.35
Depression Endpoint (Day 14)	12.93 score on a scale Standard Deviation 8.56	18.31 score on a scale Standard Deviation 11.86

SECONDARY outcome

Timeframe: Treatment expectations were measured during the administration of the intervention (Day 1) and at the end of the study (Day 14)

Population: Participants in the No-Treatment Control group were not administered the Treatment Expectations Questionnaire because they did not receive any treatment.

Participants in the open-label placebo group rated their expectations of the open-label placebo treatment using representative questions (10-items) from each sub-scale of the Treatment Expectations Questionnaire (TEX-Q; Alberts et al. (2020). Two subscales were calculated from exploratory factor analysis: Expected benefits and Expected harm. The range for expected benefits ranged from 0-10 with higher scores indicating greater benefits from the OLP. The range for expected harm also ranged from 0-10 with higher scores indicating expecting more harm.

Outcome measures

Outcome measures
Measure	Non-Deceptive Placebo n=29 Participants The NDP group was informed that the purpose of the study was to test a mind-body intervention that might help participants deal with the stress and anxiety that they are feeling during the pandemic. The intervention included two videos that introduced the effects of non-deceptive placebos, followed by a presentation on up-to-date non-deceptive placebo research. The participants then received instruction on how they would take their non-deceptive placebos for the next two weeks. Participants were asked to complete daily pill-taking adherence surveys (\~5 min) and weekly at midpoint (1-week) and endpoint (2-week). Non-Deceptive Placebo: The placebos were ordered through Amazon from Zeebo® (Zeebo, Zeebo Effect, LLC, South Burlington, Vermont, USA). The placebos in this study were blue and white capsules containing Microcrystalline cellulose (an inert fiber). Ingredients include ones that are typically used to make pills including silica, gelatin, titanium dioxide, red #3 food coloring, and blue #1 food coloring. Placebo capsules were free of any active ingredients. These bottles were not branded specifically for the experiment, including the brand name ("Zeebo Relief"), description of the contents, directions, and a disclaimer. The investigators chose to not include a custom label for transparency and in order to increase "non-deceptive" placebo effects. Participants were instructed to take two pills a day, one in the morning and one in the evening.	No-Treatment Control The Control group did not receive an intervention. Instead, participants were informed that the purpose of the study was to track individual psychological and physical health over longer time periods in the context of the pandemic. Participants were asked to complete weekly questionnaires at midpoint (1-week) and endpoint (2-week).
Treatment Expectations Expected Benefits (Day 1)	6.30 score on a scale Standard Deviation 2.09	—
Treatment Expectations Expected Benefits (Day 14)	5.21 score on a scale Standard Deviation 2.17	—
Treatment Expectations Expected Harm (Day 1)	.53 score on a scale Standard Deviation 1.06	—
Treatment Expectations Expected Harm (Day 14)	.32 score on a scale Standard Deviation .58	—

SECONDARY outcome

Timeframe: Treatment adherence was measured daily for 14 days beginning after intervention administration (Day 1).

Population: Treatment adherence was not measured in the No-Treatment Control group because they did not receive the treatment.

Participants in the open-label placebo group were instructed to take two placebo pills a day for 14 days (28 placebo pills). Treatment adherence was measured as the percentage of placebo pills taken by each participant (number of pills taken / 28 \* 100).

Outcome measures

Outcome measures
Measure	Non-Deceptive Placebo n=29 Participants The NDP group was informed that the purpose of the study was to test a mind-body intervention that might help participants deal with the stress and anxiety that they are feeling during the pandemic. The intervention included two videos that introduced the effects of non-deceptive placebos, followed by a presentation on up-to-date non-deceptive placebo research. The participants then received instruction on how they would take their non-deceptive placebos for the next two weeks. Participants were asked to complete daily pill-taking adherence surveys (\~5 min) and weekly at midpoint (1-week) and endpoint (2-week). Non-Deceptive Placebo: The placebos were ordered through Amazon from Zeebo® (Zeebo, Zeebo Effect, LLC, South Burlington, Vermont, USA). The placebos in this study were blue and white capsules containing Microcrystalline cellulose (an inert fiber). Ingredients include ones that are typically used to make pills including silica, gelatin, titanium dioxide, red #3 food coloring, and blue #1 food coloring. Placebo capsules were free of any active ingredients. These bottles were not branded specifically for the experiment, including the brand name ("Zeebo Relief"), description of the contents, directions, and a disclaimer. The investigators chose to not include a custom label for transparency and in order to increase "non-deceptive" placebo effects. Participants were instructed to take two pills a day, one in the morning and one in the evening.	No-Treatment Control The Control group did not receive an intervention. Instead, participants were informed that the purpose of the study was to track individual psychological and physical health over longer time periods in the context of the pandemic. Participants were asked to complete weekly questionnaires at midpoint (1-week) and endpoint (2-week).
Treatment Adherence	92.5 percentage of pills taken Standard Deviation 9.7	—

SECONDARY outcome

Timeframe: Ratings of intervention feasibility were measured at Endpoint (Day 14)

Population: Intervention feasibility was not measured in the No-Treatment Control group because they did not receive the treatment.

Intervention feasibility was measured using the Feasibility of Intervention Measure (FIM; Weiner et al., 2017). The FIM is a 4-item self-report measure that assesses the extent to which an intervention can be successfully implemented within a given setting. The items are averaged with scores ranging from 1-5 with higher numbers indicating that the OLP intervention is easy to use and doable.

Outcome measures

Outcome measures
Measure	Non-Deceptive Placebo n=29 Participants The NDP group was informed that the purpose of the study was to test a mind-body intervention that might help participants deal with the stress and anxiety that they are feeling during the pandemic. The intervention included two videos that introduced the effects of non-deceptive placebos, followed by a presentation on up-to-date non-deceptive placebo research. The participants then received instruction on how they would take their non-deceptive placebos for the next two weeks. Participants were asked to complete daily pill-taking adherence surveys (\~5 min) and weekly at midpoint (1-week) and endpoint (2-week). Non-Deceptive Placebo: The placebos were ordered through Amazon from Zeebo® (Zeebo, Zeebo Effect, LLC, South Burlington, Vermont, USA). The placebos in this study were blue and white capsules containing Microcrystalline cellulose (an inert fiber). Ingredients include ones that are typically used to make pills including silica, gelatin, titanium dioxide, red #3 food coloring, and blue #1 food coloring. Placebo capsules were free of any active ingredients. These bottles were not branded specifically for the experiment, including the brand name ("Zeebo Relief"), description of the contents, directions, and a disclaimer. The investigators chose to not include a custom label for transparency and in order to increase "non-deceptive" placebo effects. Participants were instructed to take two pills a day, one in the morning and one in the evening.	No-Treatment Control The Control group did not receive an intervention. Instead, participants were informed that the purpose of the study was to track individual psychological and physical health over longer time periods in the context of the pandemic. Participants were asked to complete weekly questionnaires at midpoint (1-week) and endpoint (2-week).
Intervention Feasibility	4.31 score on a scale Standard Deviation .54	—

SECONDARY outcome

Timeframe: Ratings of intervention acceptability were measured at Endpoint (Day 14)

Population: Intervention acceptability was not measured in the No-Treatment Control group because they did not receive the treatment.

Intervention acceptability was measured using the Acceptability of Intervention Measure (AIM; Weiner et al., 2017). The AIM is a 4-item self-report measure that assesses the extent to which an intervention is perceived to be satisfactory, adequate, and appealing. The items are averaged with scores ranging from 1-5 with higher numbers indicating that the OLP intervention is satisfactory and appealing.

Outcome measures

Outcome measures
Measure	Non-Deceptive Placebo n=29 Participants The NDP group was informed that the purpose of the study was to test a mind-body intervention that might help participants deal with the stress and anxiety that they are feeling during the pandemic. The intervention included two videos that introduced the effects of non-deceptive placebos, followed by a presentation on up-to-date non-deceptive placebo research. The participants then received instruction on how they would take their non-deceptive placebos for the next two weeks. Participants were asked to complete daily pill-taking adherence surveys (\~5 min) and weekly at midpoint (1-week) and endpoint (2-week). Non-Deceptive Placebo: The placebos were ordered through Amazon from Zeebo® (Zeebo, Zeebo Effect, LLC, South Burlington, Vermont, USA). The placebos in this study were blue and white capsules containing Microcrystalline cellulose (an inert fiber). Ingredients include ones that are typically used to make pills including silica, gelatin, titanium dioxide, red #3 food coloring, and blue #1 food coloring. Placebo capsules were free of any active ingredients. These bottles were not branded specifically for the experiment, including the brand name ("Zeebo Relief"), description of the contents, directions, and a disclaimer. The investigators chose to not include a custom label for transparency and in order to increase "non-deceptive" placebo effects. Participants were instructed to take two pills a day, one in the morning and one in the evening.	No-Treatment Control The Control group did not receive an intervention. Instead, participants were informed that the purpose of the study was to track individual psychological and physical health over longer time periods in the context of the pandemic. Participants were asked to complete weekly questionnaires at midpoint (1-week) and endpoint (2-week).
Intervention Acceptability	4.03 score on a scale Standard Deviation .72	—

SECONDARY outcome

Timeframe: Ratings of intervention appropriateness were measured at Endpoint (Day 14)

Population: Intervention Appropriateness was not measured in the No-Treatment Control group because they did not receive the treatment.

Intervention appropriateness was measured using the Intervention Appropriateness Measure (IAM; Weiner et al., 2017). The IAM is a 4-item self-report measure that assesses the extent to which an intervention is perceived to be fitting, relevant, and compatible with a population or setting to address a particular problem. The items are averaged with scores ranging from 1-5 with higher numbers indicating that the OLP intervention is perceived to be fitting, relevant, and compatible with a population or setting to address a particular problem.

Outcome measures

Outcome measures
Measure	Non-Deceptive Placebo n=29 Participants The NDP group was informed that the purpose of the study was to test a mind-body intervention that might help participants deal with the stress and anxiety that they are feeling during the pandemic. The intervention included two videos that introduced the effects of non-deceptive placebos, followed by a presentation on up-to-date non-deceptive placebo research. The participants then received instruction on how they would take their non-deceptive placebos for the next two weeks. Participants were asked to complete daily pill-taking adherence surveys (\~5 min) and weekly at midpoint (1-week) and endpoint (2-week). Non-Deceptive Placebo: The placebos were ordered through Amazon from Zeebo® (Zeebo, Zeebo Effect, LLC, South Burlington, Vermont, USA). The placebos in this study were blue and white capsules containing Microcrystalline cellulose (an inert fiber). Ingredients include ones that are typically used to make pills including silica, gelatin, titanium dioxide, red #3 food coloring, and blue #1 food coloring. Placebo capsules were free of any active ingredients. These bottles were not branded specifically for the experiment, including the brand name ("Zeebo Relief"), description of the contents, directions, and a disclaimer. The investigators chose to not include a custom label for transparency and in order to increase "non-deceptive" placebo effects. Participants were instructed to take two pills a day, one in the morning and one in the evening.	No-Treatment Control The Control group did not receive an intervention. Instead, participants were informed that the purpose of the study was to track individual psychological and physical health over longer time periods in the context of the pandemic. Participants were asked to complete weekly questionnaires at midpoint (1-week) and endpoint (2-week).
Intervention Appropriateness	3.98 score on scale Standard Deviation .69	—

Adverse Events

Non-Deceptive Placebo

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

No-Treatment Control

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Dr. Jason Moser

Michigan State University

Phone: 517-355-2159

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place

Measure	Non-Deceptive Placebo n=32 Participants The NDP group was informed that the purpose of the study was to test a mind-body intervention that might help participants deal with the stress and anxiety that they are feeling during the pandemic. The intervention included two videos that introduced the effects of non-deceptive placebos, followed by a presentation on up-to-date non-deceptive placebo research. The participants then received instruction on how they would take their non-deceptive placebos for the next two weeks. Participants were asked to complete daily pill-taking adherence surveys (\~5 min) and weekly at midpoint (1-week) and endpoint (2-week). Non-Deceptive Placebo: The placebos were ordered through Amazon from Zeebo® (Zeebo, Zeebo Effect, LLC, South Burlington, Vermont, USA). The placebos in this study were blue and white capsules containing Microcrystalline cellulose (an inert fiber). Ingredients include ones that are typically used to make pills including silica, gelatin, titanium dioxide, red #3 food coloring, and blue #1 food coloring. Placebo capsules were free of any active ingredients. These bottles were not branded specifically for the experiment, including the brand name ("Zeebo Relief"), description of the contents, directions, and a disclaimer. The investigators chose to not include a custom label for transparency and in order to increase "non-deceptive" placebo effects. Participants were instructed to take two pills a day, one in the morning and one in the evening.	No-Treatment Control n=32 Participants The Control group did not receive an intervention. Instead, participants were informed that the purpose of the study was to track individual psychological and physical health over longer time periods in the context of the pandemic. Participants were asked to complete weekly questionnaires at midpoint (1-week) and endpoint (2-week).	Total n=64 Participants Total of all reporting groups
Age, Continuous	21.22 years n=32 Participants	20.97 years n=32 Participants	21.09 years n=64 Participants
Sex/Gender, Customized Male	3 Participants n=32 Participants	3 Participants n=32 Participants	6 Participants n=64 Participants
Sex/Gender, Customized Female	29 Participants n=32 Participants	29 Participants n=32 Participants	58 Participants n=64 Participants
Sex/Gender, Customized Intersex	0 Participants n=32 Participants	0 Participants n=32 Participants	0 Participants n=64 Participants
Sex/Gender, Customized Not Listed	0 Participants n=32 Participants	0 Participants n=32 Participants	0 Participants n=64 Participants
Race/Ethnicity, Customized Native American/ American Indian/Alaskan Native/ Indigenous	0 Participants n=32 Participants	0 Participants n=32 Participants	0 Participants n=64 Participants
Race/Ethnicity, Customized East Asian (Korean, Japanese, Chinese, etc.)	0 Participants n=32 Participants	5 Participants n=32 Participants	5 Participants n=64 Participants
Race/Ethnicity, Customized Southeast Asian (Vietnamese, Cambodian, Filipino, etc.)	2 Participants n=32 Participants	1 Participants n=32 Participants	3 Participants n=64 Participants
Race/Ethnicity, Customized South Asian (Indian, Pakistani, Sri Lanka, etc.)	3 Participants n=32 Participants	3 Participants n=32 Participants	6 Participants n=64 Participants
Race/Ethnicity, Customized Black/ African American	0 Participants n=32 Participants	1 Participants n=32 Participants	1 Participants n=64 Participants
Race/Ethnicity, Customized Latinx/ Hispanic	0 Participants n=32 Participants	0 Participants n=32 Participants	0 Participants n=64 Participants
Race/Ethnicity, Customized Middle Eastern/ North African	0 Participants n=32 Participants	1 Participants n=32 Participants	1 Participants n=64 Participants
Race/Ethnicity, Customized Native Hawaiian/ Pacific Islander	0 Participants n=32 Participants	0 Participants n=32 Participants	0 Participants n=64 Participants
Race/Ethnicity, Customized White/ European	26 Participants n=32 Participants	18 Participants n=32 Participants	44 Participants n=64 Participants
Race/Ethnicity, Customized Multiracial	1 Participants n=32 Participants	3 Participants n=32 Participants	4 Participants n=64 Participants
Region of Enrollment United States	32 participants n=32 Participants	32 participants n=32 Participants	64 participants n=64 Participants
COVID Stress Scale (CSS)	34.70 units on a scale STANDARD_DEVIATION 18.495 • n=30 Participants • Two participants in the non-deceptive placebo group dropped out before baseline assessment.	35.13 units on a scale STANDARD_DEVIATION 20.500 • n=32 Participants • Two participants in the non-deceptive placebo group dropped out before baseline assessment.	34.92 units on a scale STANDARD_DEVIATION 19.397 • n=62 Participants • Two participants in the non-deceptive placebo group dropped out before baseline assessment.
Perceived Stress Scale (PSS)	22.47 units on a scale STANDARD_DEVIATION 6.632 • n=30 Participants • Two participants in the non-deceptive placebo group dropped out before baseline assessment.	20.34 units on a scale STANDARD_DEVIATION 7.489 • n=32 Participants • Two participants in the non-deceptive placebo group dropped out before baseline assessment.	21.37 units on a scale STANDARD_DEVIATION 7.109 • n=62 Participants • Two participants in the non-deceptive placebo group dropped out before baseline assessment.
PROMIS Anxiety Short Form	25.77 units on a scale STANDARD_DEVIATION 6.694 • n=30 Participants • Two participants in the non-deceptive placebo group dropped out before baseline assessment.	23.69 units on a scale STANDARD_DEVIATION 6.621 • n=32 Participants • Two participants in the non-deceptive placebo group dropped out before baseline assessment.	24.69 units on a scale STANDARD_DEVIATION 6.684 • n=62 Participants • Two participants in the non-deceptive placebo group dropped out before baseline assessment.
Center for Epidemiological Studies Depression Scale (CES-D)	22.80 units on a scale STANDARD_DEVIATION 10.662 • n=30 Participants • Two participants in the non-deceptive placebo group dropped out before baseline assessment.	20.75 units on a scale STANDARD_DEVIATION 12.104 • n=32 Participants • Two participants in the non-deceptive placebo group dropped out before baseline assessment.	21.74 units on a scale STANDARD_DEVIATION 11.383 • n=62 Participants • Two participants in the non-deceptive placebo group dropped out before baseline assessment.