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Remote Guided Caffeine Reduction

Remote Guided Caffeine Reduction

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04560595
Enrollment
109
Registered
2020-09-23
Start date
2020-09-10
Completion date
2023-10-01
Last updated
2025-01-14

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

Conditions

Anxiety, Anxiety Disorders, Caffeine, Caffeine Abuse, Caffeine Dependence, Caffeine-Induced Anxiety Disorder, Caffeine-Induced Sleep Disorder, Without Use Disorder, Caffeine; Sleep Disorder, Caffeine Withdrawal, Diarrhea, Gastrointestinal Dysfunction, Heartburn, Insomnia, Sleep Disorder, Sleep Disturbance, Sleep Initiation and Maintenance Disorders

Keywords

caffeine, caffeine reduction, online study, manualized treatment, caffeine fading, remote intervention, remote trial

Brief summary

The purpose of this online research study is to determine whether or not a gradual caffeine reduction program developed at Johns Hopkins can help people reduce their caffeine use. The investigators will provide materials to help guide caffeine reduction and ask questions to track caffeine use over several weeks. The investigators will also assess how reducing caffeine may benefit common caffeine-related problems such as anxiety, sleep disturbances, and gastrointestinal distress. The study will also determine whether or not people like participating in this caffeine reduction program in an online format.

Detailed description

There is emerging evidence that some individuals have difficulty cutting down or eliminating caffeine consumption in spite of clinically significant problems exacerbated by caffeine use. This study will evaluate whether a caffeine reduction program developed at Johns Hopkins can help people reduce their caffeine use in an online format. Volunteers will participate in an intervention study conducted entirely online, including video visits for screening, instructions for caffeine reduction, and follow up. The study also involves filling out online surveys sent via email and text message. During screening, participants will be asked questions about their personal characteristics including demographic information, weekly caffeine consumption, and general medical history. Participants who are determined to be eligible after screening will be randomized to either the immediate or delayed treatment group. Those in the immediate treatment group will have their next session immediately after screening while those in the delayed treatment group will have their next session 7 weeks after screening. At this session, participants receive a digital copy of a caffeine reduction manual and instructions on how to gradually cut down caffeine. After this, participants will complete weekly online surveys over six weeks. Participants will complete two follow-up video visits at 7 and 14 weeks after participants received the caffeine reduction instructions. The investigators will measure caffeine consumption over time using the online surveys and interview questions during video visits, and the investigators will also measure how various caffeine related problems may improve during caffeine reduction, such as sleep problems, gastrointestinal issues, and anxiety. During the end of study sessions, participants will answer questions related to acceptability of the online format and report on participants' current caffeine use.

Interventions

BEHAVIORALCaffeine Reduction Manual

We will provide participants with a Guide to Caffeine Reduction and Cessation in order to help the reduce their caffeine use and determine their ratings of treatment acceptability.

Sponsors

National Institute on Drug Abuse (NIDA)
CollaboratorNIH
Johns Hopkins University
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Intervention model description

Caffeine consumption and secondary measures will be examined before, during, and after the caffeine reduction intervention and compared between immediate and delayed treatment groups.

Eligibility

Sex/Gender
ALL
Age
18 Years to 75 Years
Healthy volunteers
Yes

Inclusion criteria

* 18-75 years old * Reside in the United States * Read, write, and speak English fluently * Able to access a video camera on a smart phone, tablet, or other computer * Able to receive text messages or emails (or both) * Suitable caffeine consumption * Indicate suitable reason for caffeine reduction * Interested in getting help to gradually reduce or eliminate caffeine consumption as part of a research study

Exclusion criteria

* Any current medical or psychiatric disorder or symptoms that, in the opinion of the investigators, may interfere with or preclude completion of the study \[many psychiatric or medical concerns such as insomnia or anxiety are not anticipated to interfere with study participation and will not generally be exclusionary\]

Design outcomes

Primary

MeasureTime frameDescription
Number of Participants With Treatment Retention as Assessed by Number of Participants With Completed AssessmentsTreatment Visit, 7-Week Follow-Up, 14-Week Follow-UpTo determine to what extent participants will engage with a remote caffeine reduction intervention for caffeine-related problems and find it acceptable, we will calculate the percentage of completed assessments for each video visit among eligible participants.
Treatment Acceptability as Assessed by Treatment Acceptability Questionnaire7 weeks Follow-Up visitAt the 7 Weeks Follow-Up video visit, we will use an internally-developed standardized treatment acceptability questionnaire to determine self-reported agreement with two items on the treatment acceptability survey (i.e., Overall, was the Guide to Caffeine Reduction and Cessation easy to use?, and Overall, was the guide to Caffeine reduction and Cessation helpful?). Each question is scored on a scale from 0-3, for a total score range of 0-6, where lower scores indicate less acceptability (e.g., 0=not at all easy, not at all helpful; 3 = very easy, very helpful).

Secondary

MeasureTime frameDescription
Change in Anxiety as Assessed by the PROMIS-Anxiety-8aBaseline, 7-Week Follow-Up, 14-Week Follow-UpTo determine whether caffeine reduction is accompanied by a reduction in day-to-day anxiety, we will utilize the Patient-Reported Outcomes Measurement Information System (PROMIS) Anxiety 8a assessment. The questionnaire asks the extent to which anxiety-related items affected the participants over the past 7 days on a scale of 1 (never) to 5 (always) with a total raw score range of 8-40 in which higher scores reflect greater anxiety. Raw scores are then translated into a standardized T-score with a mean of 50 and a standard deviation (SD) of 10. A higher PROMIS T-score represents more of the concept being measured. For negatively-worded concepts like anxiety, a T-score of 60 is one SD worse than average. By comparison, an anxiety T-score of 40 is one SD better than average. A score of less than 55 is none to slight, 55.0-59.9 is mild, 60.0-69.9 is moderate, and 70 and over is severe.
Change in Anxiety as Assessed by the GAD-7Baseline, 7-Week Follow-Up, 14-Week Follow-UpTo determine whether caffeine reduction is accompanied by a reduction in day-to-day anxiety, we will utilize the Generalized Anxiety Disorder-7 (GAD-7). The GAD-7 consists of items asking the participant to rate on a scale of 0 (not at all) to 3 (nearly every day) the extent they have experienced anxiety related symptoms. The scoring range is 0-21 and higher scores indicate greater anxiety related symptoms.
Change in Sleep Problems as Assessed by the PROMIS Sleep Disturbance 8aBaseline, 7-Week Follow-Up, 14-Week Follow-UpTo determine whether caffeine reduction is accompanied by a reduction in sleep problems, we will utilize the PROMIS Sleep Disturbance 8a assessment. The questionnaire asks the extent to which sleep-related items affected the participants over the past 7 days on a scale of 1 (not at all) to 5 (very much). The raw scoring range is 8-40 and higher scores reflect greater sleep disturbance. Raw scores are then translated into a standardized T-score with a mean of 50 and a standard deviation (SD) of 10. A higher PROMIS T-score represents more of the concept being measured. For negatively-worded concepts like sleep disturbance, a T-score of 60 is one SD worse than average. By comparison, T-score of 40 is one SD better than average. A T-score of 50 or above is often considered a clinically significant level of sleep disturbance.
Change in Caffeine Consumption (in Milligrams)Baseline, Treatment Visit, 7-Week Follow-Up, 14-Week Follow-UpTo determine to what extent participants are successfully able to reduce their caffeine consumption following the remote intervention, we will assess caffeine consumption as determined by the standardized caffeine assessments at 7 week post-treatment follow-ups and compare this with consumption at the screening televisit. Based on participant responses to the number, type, and amount of caffeinated beverages, caffeine consumption is calculated at each assessment in milligrams (mg).
Change in Gastrointestinal Problems as Assessed by the PROMIS Reflux-13aBaseline, 7-Week Follow-Up, 14-Week Follow-UpTo determine whether caffeine reduction is accompanied by a reduction in gastrointestinal problems, we will utilize the PROMIS Reflux-13a. These items ask the extent to which gastrointestinal-related items affected the participants over the past 7 days on a scale of 1 (never) to 5 (always). The scoring range of raw scores is 13-65 and higher scores reflect greater gastrointestinal problems. Raw scores are then translated into a standardized T-score with a mean of 50 and a standard deviation (SD) of 10. A higher PROMIS T-score represents more of the concept being measured. For negatively-worded concepts like reflux, a T-score of 60 is one SD worse than average. By comparison, an anxiety T-score of 40 is one SD better than average.
Change in Gastrointestinal Problems as Assessed by the GSRSBaseline, 7-Week Follow-Up, 14-Week Follow-UpTo determine whether caffeine reduction is accompanied by a reduction in gastrointestinal problems, we will utilize the Gastrointestinal Symptoms Rating Scale (GSRS) which consists of 15 items describing gastrointestinal distress where responses range from 0 (no discomfort at all) to 6 (very severe discomfort). The scoring range is 0-90 and higher scores indicate more severe gastrointestinal symptoms.
Change in Gastrointestinal Problems as Assessed by the PROMIS Diarrhea-6aBaseline, 7-Week Follow-Up, 14-Week Follow-UpTo determine whether caffeine reduction is accompanied by a reduction in gastrointestinal problems, we will utilize the PROMIS Diarrhea-6a. These items ask the extent to which gastrointestinal-related items affected the participants over the past 7 days on a scale of 1 (never) to 5 (always). The raw scoring range is 6-30 and higher scores reflect greater gastrointestinal problems. Raw scores are then translated into a standardized T-score with a mean of 50 and a standard deviation (SD) of 10. A higher PROMIS T-score represents more of the concept being measured. For negatively-worded concepts like diarrhea, a T-score of 60 is one SD worse than average. By comparison, an anxiety T-score of 40 is one SD better than average.
Change in Sleep Problems as Assessed by the PSQIBaseline, 7-Week Follow-Up, 14-Week Follow-UpTo determine whether caffeine reduction is accompanied by a reduction in sleep problems, we will utilize the Pittsburgh Sleep Quality Index (PSQI), which contains 19 self-rated items and 7 sub-scales for different components where a score of 0 indicates no difficulty and a score of 3 indicates severe difficulty. The scoring range is 0-21 and higher global scores indicate greater sleep difficulties.
Change in Caffeine-related Problems as Assessed by Past-7 Days Standardized ItemsBaseline, 7-Week Follow-Up, 14-Week Follow-UpTo determine to what extent participants report improvement in common caffeine-related problems following the remote intervention, we have developed a standardized 19-Item Caffeine Use Disorder measure of the extent to which common problems related to excessive caffeine consumption bothered participants within the past 7 days, e.g., During the past 7 days, I have consumed caffeine in larger amounts or over a longer period than I intended. Participants rate the extent to which these problems bothered them on a scale from 0-3 where 0 = not at all a problem and 3 = major problem. The total possible scale range is from 0-57 (because the scores of 0-3 are summed for the 19 items). Higher sum scores on the measure indicate greater caffeine-related problems.

Countries

United States

Participant flow

Participants by arm

ArmCount
Caffeine Reduction Manual, Immediate Treatment Group
Weekly caffeine consumption is to be measured before and after using the caffeine reduction program, which has been summarized in a Guide to Caffeine Reduction and Cessation manual to help people reduce their caffeine use. Those in the immediate treatment group will receive the guide immediately after screening. Caffeine Reduction Manual: We will provide participants with a Guide to Caffeine Reduction and Cessation in order to help the reduce their caffeine use and determine their ratings of treatment acceptability.
53
Caffeine Reduction Manual, Delayed Treatment Group
Weekly caffeine consumption is to be measured before and after using the caffeine reduction program, which has been summarized in a Guide to Caffeine Reduction and Cessation manual to help people reduce their caffeine use. Those in the delayed treatment group will receive the guide seven weeks after screening. Caffeine Reduction Manual: We will provide participants with a Guide to Caffeine Reduction and Cessation in order to help the reduce their caffeine use and determine their ratings of treatment acceptability.
56
Total109

Baseline characteristics

CharacteristicCaffeine Reduction Manual, Immediate Treatment GroupCaffeine Reduction Manual, Delayed Treatment GroupTotal
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
0 Participants0 Participants0 Participants
Age, Categorical
Between 18 and 65 years
53 Participants56 Participants109 Participants
Age, Continuous45.36 years
STANDARD_DEVIATION 15.42
41.96 years
STANDARD_DEVIATION 14.14
43.61 years
STANDARD_DEVIATION 14.81
Ethnicity (NIH/OMB)
Hispanic or Latino
5 Participants1 Participants6 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
48 Participants55 Participants103 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
5 Participants5 Participants10 Participants
Race (NIH/OMB)
Black or African American
2 Participants2 Participants4 Participants
Race (NIH/OMB)
More than one race
3 Participants6 Participants9 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
1 Participants1 Participants2 Participants
Race (NIH/OMB)
White
42 Participants42 Participants84 Participants
Region of Enrollment
United States
53 Participants56 Participants109 Participants
Sex: Female, Male
Female
25 Participants29 Participants54 Participants
Sex: Female, Male
Male
28 Participants27 Participants55 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 530 / 56
other
Total, other adverse events
0 / 530 / 56
serious
Total, serious adverse events
0 / 530 / 56

Outcome results

Primary

Number of Participants With Treatment Retention as Assessed by Number of Participants With Completed Assessments

To determine to what extent participants will engage with a remote caffeine reduction intervention for caffeine-related problems and find it acceptable, we will calculate the percentage of completed assessments for each video visit among eligible participants.

Time frame: Treatment Visit, 7-Week Follow-Up, 14-Week Follow-Up

Population: All available data analyzed at each timepoint

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
Caffeine Reduction Manual, Immediate Treatment GroupNumber of Participants With Treatment Retention as Assessed by Number of Participants With Completed AssessmentsTreatment Visit51 Participants
Caffeine Reduction Manual, Immediate Treatment GroupNumber of Participants With Treatment Retention as Assessed by Number of Participants With Completed Assessments7-Week Follow-Up50 Participants
Caffeine Reduction Manual, Immediate Treatment GroupNumber of Participants With Treatment Retention as Assessed by Number of Participants With Completed Assessments14-Week Follow-Up48 Participants
Caffeine Reduction Manual, Delayed Treatment GroupNumber of Participants With Treatment Retention as Assessed by Number of Participants With Completed AssessmentsTreatment Visit51 Participants
Caffeine Reduction Manual, Delayed Treatment GroupNumber of Participants With Treatment Retention as Assessed by Number of Participants With Completed Assessments7-Week Follow-Up46 Participants
Caffeine Reduction Manual, Delayed Treatment GroupNumber of Participants With Treatment Retention as Assessed by Number of Participants With Completed Assessments14-Week Follow-Up45 Participants
Primary

Treatment Acceptability as Assessed by Treatment Acceptability Questionnaire

At the 7 Weeks Follow-Up video visit, we will use an internally-developed standardized treatment acceptability questionnaire to determine self-reported agreement with two items on the treatment acceptability survey (i.e., Overall, was the Guide to Caffeine Reduction and Cessation easy to use?, and Overall, was the guide to Caffeine reduction and Cessation helpful?). Each question is scored on a scale from 0-3, for a total score range of 0-6, where lower scores indicate less acceptability (e.g., 0=not at all easy, not at all helpful; 3 = very easy, very helpful).

Time frame: 7 weeks Follow-Up visit

Population: Analysis population consists of participants who completed the week 7 end of treatment visit.

ArmMeasureValue (MEAN)Dispersion
Caffeine Reduction Manual, Immediate Treatment GroupTreatment Acceptability as Assessed by Treatment Acceptability Questionnaire2.50 score on a scaleStandard Deviation 0.52
Caffeine Reduction Manual, Delayed Treatment GroupTreatment Acceptability as Assessed by Treatment Acceptability Questionnaire2.55 score on a scaleStandard Deviation 0.5
Secondary

Change in Anxiety as Assessed by the GAD-7

To determine whether caffeine reduction is accompanied by a reduction in day-to-day anxiety, we will utilize the Generalized Anxiety Disorder-7 (GAD-7). The GAD-7 consists of items asking the participant to rate on a scale of 0 (not at all) to 3 (nearly every day) the extent they have experienced anxiety related symptoms. The scoring range is 0-21 and higher scores indicate greater anxiety related symptoms.

Time frame: Baseline, 7-Week Follow-Up, 14-Week Follow-Up

Population: All available data analyzed at each timepoint

ArmMeasureGroupValue (MEAN)Dispersion
Caffeine Reduction Manual, Immediate Treatment GroupChange in Anxiety as Assessed by the GAD-7Baseline6.96 score on a scaleStandard Deviation 5.79
Caffeine Reduction Manual, Immediate Treatment GroupChange in Anxiety as Assessed by the GAD-77-Week Follow-Up3.76 score on a scaleStandard Deviation 4.84
Caffeine Reduction Manual, Immediate Treatment GroupChange in Anxiety as Assessed by the GAD-714-Week Follow-up3.00 score on a scaleStandard Deviation 4.34
Caffeine Reduction Manual, Delayed Treatment GroupChange in Anxiety as Assessed by the GAD-7Baseline6.13 score on a scaleStandard Deviation 5.39
Caffeine Reduction Manual, Delayed Treatment GroupChange in Anxiety as Assessed by the GAD-77-Week Follow-Up3.13 score on a scaleStandard Deviation 3.2
Caffeine Reduction Manual, Delayed Treatment GroupChange in Anxiety as Assessed by the GAD-714-Week Follow-up3.24 score on a scaleStandard Deviation 4.03
Secondary

Change in Anxiety as Assessed by the PROMIS-Anxiety-8a

To determine whether caffeine reduction is accompanied by a reduction in day-to-day anxiety, we will utilize the Patient-Reported Outcomes Measurement Information System (PROMIS) Anxiety 8a assessment. The questionnaire asks the extent to which anxiety-related items affected the participants over the past 7 days on a scale of 1 (never) to 5 (always) with a total raw score range of 8-40 in which higher scores reflect greater anxiety. Raw scores are then translated into a standardized T-score with a mean of 50 and a standard deviation (SD) of 10. A higher PROMIS T-score represents more of the concept being measured. For negatively-worded concepts like anxiety, a T-score of 60 is one SD worse than average. By comparison, an anxiety T-score of 40 is one SD better than average. A score of less than 55 is none to slight, 55.0-59.9 is mild, 60.0-69.9 is moderate, and 70 and over is severe.

Time frame: Baseline, 7-Week Follow-Up, 14-Week Follow-Up

Population: All available data analyzed at each timepoint

ArmMeasureGroupValue (MEAN)Dispersion
Caffeine Reduction Manual, Immediate Treatment GroupChange in Anxiety as Assessed by the PROMIS-Anxiety-8aBaseline57.31 T-scoreStandard Deviation 7.3
Caffeine Reduction Manual, Immediate Treatment GroupChange in Anxiety as Assessed by the PROMIS-Anxiety-8a7-Week Follow-Up49.78 T-scoreStandard Deviation 8.62
Caffeine Reduction Manual, Immediate Treatment GroupChange in Anxiety as Assessed by the PROMIS-Anxiety-8a14-Week Follow-Up49.82 T-scoreStandard Deviation 7.69
Caffeine Reduction Manual, Delayed Treatment GroupChange in Anxiety as Assessed by the PROMIS-Anxiety-8aBaseline57.38 T-scoreStandard Deviation 5.96
Caffeine Reduction Manual, Delayed Treatment GroupChange in Anxiety as Assessed by the PROMIS-Anxiety-8a7-Week Follow-Up49.55 T-scoreStandard Deviation 7.44
Caffeine Reduction Manual, Delayed Treatment GroupChange in Anxiety as Assessed by the PROMIS-Anxiety-8a14-Week Follow-Up50.6 T-scoreStandard Deviation 8.78
Secondary

Change in Caffeine Consumption (in Milligrams)

To determine to what extent participants are successfully able to reduce their caffeine consumption following the remote intervention, we will assess caffeine consumption as determined by the standardized caffeine assessments at 7 week post-treatment follow-ups and compare this with consumption at the screening televisit. Based on participant responses to the number, type, and amount of caffeinated beverages, caffeine consumption is calculated at each assessment in milligrams (mg).

Time frame: Baseline, Treatment Visit, 7-Week Follow-Up, 14-Week Follow-Up

Population: All available data analyzed at each timepoint

ArmMeasureGroupValue (MEAN)Dispersion
Caffeine Reduction Manual, Immediate Treatment GroupChange in Caffeine Consumption (in Milligrams)Treatment Visit602.90 milligrams of caffeineStandard Deviation 334.29
Caffeine Reduction Manual, Immediate Treatment GroupChange in Caffeine Consumption (in Milligrams)14-Week Follow-Up219.61 milligrams of caffeineStandard Deviation 199.06
Caffeine Reduction Manual, Immediate Treatment GroupChange in Caffeine Consumption (in Milligrams)7-Week Follow-Up221.58 milligrams of caffeineStandard Deviation 235.6
Caffeine Reduction Manual, Immediate Treatment GroupChange in Caffeine Consumption (in Milligrams)Baseline Visit617.34 milligrams of caffeineStandard Deviation 354.82
Caffeine Reduction Manual, Delayed Treatment GroupChange in Caffeine Consumption (in Milligrams)Baseline Visit516.30 milligrams of caffeineStandard Deviation 218.79
Caffeine Reduction Manual, Delayed Treatment GroupChange in Caffeine Consumption (in Milligrams)Treatment Visit553.60 milligrams of caffeineStandard Deviation 246.62
Caffeine Reduction Manual, Delayed Treatment GroupChange in Caffeine Consumption (in Milligrams)7-Week Follow-Up173.14 milligrams of caffeineStandard Deviation 161.72
Caffeine Reduction Manual, Delayed Treatment GroupChange in Caffeine Consumption (in Milligrams)14-Week Follow-Up195.56 milligrams of caffeineStandard Deviation 207.39
Secondary

Change in Caffeine-related Problems as Assessed by Past-7 Days Standardized Items

To determine to what extent participants report improvement in common caffeine-related problems following the remote intervention, we have developed a standardized 19-Item Caffeine Use Disorder measure of the extent to which common problems related to excessive caffeine consumption bothered participants within the past 7 days, e.g., During the past 7 days, I have consumed caffeine in larger amounts or over a longer period than I intended. Participants rate the extent to which these problems bothered them on a scale from 0-3 where 0 = not at all a problem and 3 = major problem. The total possible scale range is from 0-57 (because the scores of 0-3 are summed for the 19 items). Higher sum scores on the measure indicate greater caffeine-related problems.

Time frame: Baseline, 7-Week Follow-Up, 14-Week Follow-Up

Population: All available data analyzed at each timepoint

ArmMeasureGroupValue (MEAN)Dispersion
Caffeine Reduction Manual, Immediate Treatment GroupChange in Caffeine-related Problems as Assessed by Past-7 Days Standardized ItemsBaseline17.85 score on a scaleStandard Deviation 10.57
Caffeine Reduction Manual, Immediate Treatment GroupChange in Caffeine-related Problems as Assessed by Past-7 Days Standardized Items7-Week Follow-Up5.52 score on a scaleStandard Deviation 4.89
Caffeine Reduction Manual, Immediate Treatment GroupChange in Caffeine-related Problems as Assessed by Past-7 Days Standardized Items14-Week Follow-Up4.26 score on a scaleStandard Deviation 6.25
Caffeine Reduction Manual, Delayed Treatment GroupChange in Caffeine-related Problems as Assessed by Past-7 Days Standardized ItemsBaseline19.23 score on a scaleStandard Deviation 10.88
Caffeine Reduction Manual, Delayed Treatment GroupChange in Caffeine-related Problems as Assessed by Past-7 Days Standardized Items7-Week Follow-Up6.28 score on a scaleStandard Deviation 5.92
Caffeine Reduction Manual, Delayed Treatment GroupChange in Caffeine-related Problems as Assessed by Past-7 Days Standardized Items14-Week Follow-Up4.69 score on a scaleStandard Deviation 5.53
Secondary

Change in Gastrointestinal Problems as Assessed by the GSRS

To determine whether caffeine reduction is accompanied by a reduction in gastrointestinal problems, we will utilize the Gastrointestinal Symptoms Rating Scale (GSRS) which consists of 15 items describing gastrointestinal distress where responses range from 0 (no discomfort at all) to 6 (very severe discomfort). The scoring range is 0-90 and higher scores indicate more severe gastrointestinal symptoms.

Time frame: Baseline, 7-Week Follow-Up, 14-Week Follow-Up

Population: All available data analyzed at each timepoint.

ArmMeasureGroupValue (MEAN)Dispersion
Caffeine Reduction Manual, Immediate Treatment GroupChange in Gastrointestinal Problems as Assessed by the GSRSBaseline16.11 score on a scaleStandard Deviation 12.84
Caffeine Reduction Manual, Immediate Treatment GroupChange in Gastrointestinal Problems as Assessed by the GSRS7-Week Follow-Up8.08 score on a scaleStandard Deviation 8.28
Caffeine Reduction Manual, Immediate Treatment GroupChange in Gastrointestinal Problems as Assessed by the GSRS14-Week Follow-Up6.96 score on a scaleStandard Deviation 9.36
Caffeine Reduction Manual, Delayed Treatment GroupChange in Gastrointestinal Problems as Assessed by the GSRSBaseline17.64 score on a scaleStandard Deviation 15.6
Caffeine Reduction Manual, Delayed Treatment GroupChange in Gastrointestinal Problems as Assessed by the GSRS7-Week Follow-Up8.98 score on a scaleStandard Deviation 8.86
Caffeine Reduction Manual, Delayed Treatment GroupChange in Gastrointestinal Problems as Assessed by the GSRS14-Week Follow-Up9.11 score on a scaleStandard Deviation 9.11
Secondary

Change in Gastrointestinal Problems as Assessed by the PROMIS Diarrhea-6a

To determine whether caffeine reduction is accompanied by a reduction in gastrointestinal problems, we will utilize the PROMIS Diarrhea-6a. These items ask the extent to which gastrointestinal-related items affected the participants over the past 7 days on a scale of 1 (never) to 5 (always). The raw scoring range is 6-30 and higher scores reflect greater gastrointestinal problems. Raw scores are then translated into a standardized T-score with a mean of 50 and a standard deviation (SD) of 10. A higher PROMIS T-score represents more of the concept being measured. For negatively-worded concepts like diarrhea, a T-score of 60 is one SD worse than average. By comparison, an anxiety T-score of 40 is one SD better than average.

Time frame: Baseline, 7-Week Follow-Up, 14-Week Follow-Up

Population: All available data analyzed at each timepoint.

ArmMeasureGroupValue (MEAN)Dispersion
Caffeine Reduction Manual, Immediate Treatment GroupChange in Gastrointestinal Problems as Assessed by the PROMIS Diarrhea-6aBaseline51.31 T-scoreStandard Deviation 9.07
Caffeine Reduction Manual, Immediate Treatment GroupChange in Gastrointestinal Problems as Assessed by the PROMIS Diarrhea-6a7-Week Follow-Up43.55 T-scoreStandard Deviation 7.05
Caffeine Reduction Manual, Immediate Treatment GroupChange in Gastrointestinal Problems as Assessed by the PROMIS Diarrhea-6a14-Week Follow-Up44.35 T-scoreStandard Deviation 7.59
Caffeine Reduction Manual, Delayed Treatment GroupChange in Gastrointestinal Problems as Assessed by the PROMIS Diarrhea-6aBaseline50.70 T-scoreStandard Deviation 8.81
Caffeine Reduction Manual, Delayed Treatment GroupChange in Gastrointestinal Problems as Assessed by the PROMIS Diarrhea-6a7-Week Follow-Up43.61 T-scoreStandard Deviation 5.92
Caffeine Reduction Manual, Delayed Treatment GroupChange in Gastrointestinal Problems as Assessed by the PROMIS Diarrhea-6a14-Week Follow-Up45.02 T-scoreStandard Deviation 6.91
Secondary

Change in Gastrointestinal Problems as Assessed by the PROMIS Reflux-13a

To determine whether caffeine reduction is accompanied by a reduction in gastrointestinal problems, we will utilize the PROMIS Reflux-13a. These items ask the extent to which gastrointestinal-related items affected the participants over the past 7 days on a scale of 1 (never) to 5 (always). The scoring range of raw scores is 13-65 and higher scores reflect greater gastrointestinal problems. Raw scores are then translated into a standardized T-score with a mean of 50 and a standard deviation (SD) of 10. A higher PROMIS T-score represents more of the concept being measured. For negatively-worded concepts like reflux, a T-score of 60 is one SD worse than average. By comparison, an anxiety T-score of 40 is one SD better than average.

Time frame: Baseline, 7-Week Follow-Up, 14-Week Follow-Up

Population: All available data analyzed at each timepoint.

ArmMeasureGroupValue (MEAN)Dispersion
Caffeine Reduction Manual, Immediate Treatment GroupChange in Gastrointestinal Problems as Assessed by the PROMIS Reflux-13aBaseline48.35 T-scoreStandard Deviation 8.71
Caffeine Reduction Manual, Immediate Treatment GroupChange in Gastrointestinal Problems as Assessed by the PROMIS Reflux-13a7-Week Follow-Up40.57 T-scoreStandard Deviation 7.17
Caffeine Reduction Manual, Immediate Treatment GroupChange in Gastrointestinal Problems as Assessed by the PROMIS Reflux-13a14-Week Follow-Up40.28 T-scoreStandard Deviation 7.32
Caffeine Reduction Manual, Delayed Treatment GroupChange in Gastrointestinal Problems as Assessed by the PROMIS Reflux-13aBaseline49.32 T-scoreStandard Deviation 7.49
Caffeine Reduction Manual, Delayed Treatment GroupChange in Gastrointestinal Problems as Assessed by the PROMIS Reflux-13a7-Week Follow-Up40.73 T-scoreStandard Deviation 5.88
Caffeine Reduction Manual, Delayed Treatment GroupChange in Gastrointestinal Problems as Assessed by the PROMIS Reflux-13a14-Week Follow-Up40.73 T-scoreStandard Deviation 6.34
Secondary

Change in Sleep Problems as Assessed by the PROMIS Sleep Disturbance 8a

To determine whether caffeine reduction is accompanied by a reduction in sleep problems, we will utilize the PROMIS Sleep Disturbance 8a assessment. The questionnaire asks the extent to which sleep-related items affected the participants over the past 7 days on a scale of 1 (not at all) to 5 (very much). The raw scoring range is 8-40 and higher scores reflect greater sleep disturbance. Raw scores are then translated into a standardized T-score with a mean of 50 and a standard deviation (SD) of 10. A higher PROMIS T-score represents more of the concept being measured. For negatively-worded concepts like sleep disturbance, a T-score of 60 is one SD worse than average. By comparison, T-score of 40 is one SD better than average. A T-score of 50 or above is often considered a clinically significant level of sleep disturbance.

Time frame: Baseline, 7-Week Follow-Up, 14-Week Follow-Up

Population: All available data analyzed at each timepoint

ArmMeasureGroupValue (MEAN)Dispersion
Caffeine Reduction Manual, Immediate Treatment GroupChange in Sleep Problems as Assessed by the PROMIS Sleep Disturbance 8aBaseline55.54 T-scoreStandard Deviation 6.96
Caffeine Reduction Manual, Immediate Treatment GroupChange in Sleep Problems as Assessed by the PROMIS Sleep Disturbance 8a7-Week Follow-Up47.09 T-scoreStandard Deviation 9.12
Caffeine Reduction Manual, Immediate Treatment GroupChange in Sleep Problems as Assessed by the PROMIS Sleep Disturbance 8a14-Week Follow-Up45.13 T-scoreStandard Deviation 7.17
Caffeine Reduction Manual, Delayed Treatment GroupChange in Sleep Problems as Assessed by the PROMIS Sleep Disturbance 8aBaseline53.94 T-scoreStandard Deviation 6.57
Caffeine Reduction Manual, Delayed Treatment GroupChange in Sleep Problems as Assessed by the PROMIS Sleep Disturbance 8a7-Week Follow-Up46.57 T-scoreStandard Deviation 6.74
Caffeine Reduction Manual, Delayed Treatment GroupChange in Sleep Problems as Assessed by the PROMIS Sleep Disturbance 8a14-Week Follow-Up46.20 T-scoreStandard Deviation 6.56
Secondary

Change in Sleep Problems as Assessed by the PSQI

To determine whether caffeine reduction is accompanied by a reduction in sleep problems, we will utilize the Pittsburgh Sleep Quality Index (PSQI), which contains 19 self-rated items and 7 sub-scales for different components where a score of 0 indicates no difficulty and a score of 3 indicates severe difficulty. The scoring range is 0-21 and higher global scores indicate greater sleep difficulties.

Time frame: Baseline, 7-Week Follow-Up, 14-Week Follow-Up

Population: All available data analyzed at each timepoint

ArmMeasureGroupValue (MEAN)Dispersion
Caffeine Reduction Manual, Immediate Treatment GroupChange in Sleep Problems as Assessed by the PSQIBaseline9.21 score on a scaleStandard Deviation 3.64
Caffeine Reduction Manual, Immediate Treatment GroupChange in Sleep Problems as Assessed by the PSQI7-Week Follow-Up6.80 score on a scaleStandard Deviation 3.56
Caffeine Reduction Manual, Immediate Treatment GroupChange in Sleep Problems as Assessed by the PSQI14-Week Follow-Up5.60 score on a scaleStandard Deviation 3.39
Caffeine Reduction Manual, Delayed Treatment GroupChange in Sleep Problems as Assessed by the PSQIBaseline8.96 score on a scaleStandard Deviation 3.16
Caffeine Reduction Manual, Delayed Treatment GroupChange in Sleep Problems as Assessed by the PSQI7-Week Follow-Up6.15 score on a scaleStandard Deviation 2.97
Caffeine Reduction Manual, Delayed Treatment GroupChange in Sleep Problems as Assessed by the PSQI14-Week Follow-Up5.76 score on a scaleStandard Deviation 2.8

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026