Trial · NCT02461693

Evaluating the Role of Expectations in Response to Caffeine Consumption: An RCT

NCT02461693, Not applicable, Completed, University of Alabama at Birmingham; results first posted 2017-07-12

3 sourcestrials-2026-11-12-0.5.0

Cite this record

ConductScience Library. Evaluating the Role of Expectations in Response to Caffeine Consumption: An RCT. Trials, record NCT02461693. Release trials-2026-11-12-0.5.0, 12 Nov 2026. https://conductscience.org/library/trials/NCT02461693

On this page

Trial

As registered on ClinicalTrials.gov, in the graph's capture of the registry.

Title: Evaluating the Role of Expectations in Response to Caffeine Consumption: An RCT
NCT number: NCT02461693
Status: Completed
Phases: Not applicable
Enrollment: 205 participants, actual
Lead sponsor: University of Alabama at Birmingham
Conditions: Caffeine, Affect, Cognitive Ability, General, Mood
Interventions: Caffeine, Placebo
First posted: 2015-06-03
Last updated: 2017-07-12
Results first posted: 2017-07-12
Limitations and caveats: Please refer to our publication in Psyhcological Methods

Source ClinicalTrials.gov

Registered outcomes4

Each outcome the trial registered, primary first, in ClinicalTrials.gov's words.

List	Outcome	Time frame	Description
Primary	Mood State Score on POMS-2 Test	30 minutes post pill consumption	Profile of Mood States (POMS-2)- "Volunteers rated a series of 65 mood-related adjectives with regard to how they were feeling "right now" on a scale of 0 (not at all) to 4 (extremely). The adjectives factor into six mood sub-scales: Tension-Anxiety; Depression-Dejection; Anger-Hostility; Vigor-Activity; Fatigue-Inertia; Confusion-Bewilderment and a Total Mood Disturbance score which aggregates the six sub-scales into a single variable." - from our publication. The minimum and maximum possible raw scores were: 0 and 40 for Tension-Anxiety, 0 and 52 for Depression-Dejection, 0 and 44 for Anger-Hostility, 0 and 36 for Vigor-Aactivity, 0 and 24 for Fatigue-Inertia, 0 and 40 for Confusion-Bewilderment, -36 and 200 for Total Mood Disturbance, and 0 and 24 for Friendliness. For Friendliness and Vigor-Activity, the more positively a person feels, the higher the score. For all other sub-scales and Total Mood Disturbance, the more negatively a person feels, the higher the score.
Primary	Vigilance Score on Computer-based Test Using Random, Visual Stimulus: Proportion Correct (Out of 60)	45 to 105 minutes post pill consumption	Scanning Visual Vigilance Test. "This test assesses vigilance, ability to sustain attention during long, boring, continuous tasks that generate minimal cognitive load (Fine et al, 1994; Lieberman et al, 1998; 2002). The volunteer continuously scans a computer screen to detect an infrequent, difficult-to-detect stimulus that appears at random intervals and locations for 2 s. On average, a stimulus was presented once per minute. Upon detection of the stimulus, the volunteer pressed the space bar as rapidly as possible. Whether a stimulus was detected and time required for detection was recorded. Responses before or after stimulus occurrence were false alarms. The test lasted 60 minutes." - from our publication
Primary	Vigilance Score on Computer-based Test Using Random, Visual Stimulus: Number Correct, Number of False Alarm Hits	45 to 105 minutes post pill consumption	Scanning Visual Vigilance Test. "This test assesses vigilance, ability to sustain attention during long, boring, continuous tasks that generate minimal cognitive load (Fine et al, 1994; Lieberman et al, 1998; 2002). The volunteer continuously scans a computer screen to detect an infrequent, difficult-to-detect stimulus that appears at random intervals and locations for 2 s. On average, a stimulus was presented once per minute. Upon detection of the stimulus, the volunteer pressed the space bar as rapidly as possible. Whether a stimulus was detected and time required for detection was recorded. Responses before or after stimulus occurrence were false alarms. The test lasted 60 minutes." - from our publication
Primary	Vigilance Score on Computer-based Test Using Random, Visual Stimulus: Mean Time to a Correct Hit	45 to 105 minutes post pill consumption	Scanning Visual Vigilance Test. "This test assesses vigilance, ability to sustain attention during long, boring, continuous tasks that generate minimal cognitive load (Fine et al, 1994; Lieberman et al, 1998; 2002). The volunteer continuously scans a computer screen to detect an infrequent, difficult-to-detect stimulus that appears at random intervals and locations for 2 s. On average, a stimulus was presented once per minute. Upon detection of the stimulus, the volunteer pressed the space bar as rapidly as possible. Whether a stimulus was detected and time required for detection was recorded. Responses before or after stimulus occurrence were false alarms. The test lasted 60 minutes." - from our publication

Source ClinicalTrials.gov

Outcomes4

Each outcome the trial posted results for, in ClinicalTrials.gov's words.

Type	Outcome	Time frame	Population	Units	Measured as
PRIMARY	Mood State Score on POMS-2 Test	30 minutes post pill consumption	Results are of raw data as presented in our publication	units on a scale	MEAN
PRIMARY	Vigilance Score on Computer-based Test Using Random, Visual Stimulus: Proportion Correct (Out of 60)	45 to 105 minutes post pill consumption	One participant who received the caffeine pill had to use the restroom during the vigilance testing period and had to stop the test. Due to a technicality of the computer program, her data for the vigilance test was not available for analysis.	Proportion correct	MEAN
PRIMARY	Vigilance Score on Computer-based Test Using Random, Visual Stimulus: Number Correct, Number of False Alarm Hits	45 to 105 minutes post pill consumption	One participant who received the caffeine pill had to use the restroom during the vigilance testing period and had to stop the test. Due to a technicality of the computer program, her data for the vigilance test was not available for analysis.	counts	MEAN
PRIMARY	Vigilance Score on Computer-based Test Using Random, Visual Stimulus: Mean Time to a Correct Hit	45 to 105 minutes post pill consumption	One participant who received the caffeine pill had to use the restroom during the vigilance testing period and had to stop the test. Due to a technicality of the computer program, her data for the vigilance test was not available for analysis.	seconds	MEAN

Source ClinicalTrials.gov

Results by group24

Each measurement the trial posted, group by group, in the words and numbers it posted.

Outcome	Group	Category	Value	Spread	Units
Mood State Score on POMS-2 Test	Caffeine	Total Mood Displacement	2.63	Standard Error 1.98	units on a scale
Mood State Score on POMS-2 Test	Placebo	Total Mood Displacement	14.08	Standard Error 2.86	units on a scale
Mood State Score on POMS-2 Test	Caffeine	Anger-Hostility	2.19	Standard Error 0.38	units on a scale
Mood State Score on POMS-2 Test	Placebo	Anger-Hostility	2.54	Standard Error 0.46	units on a scale
Mood State Score on POMS-2 Test	Caffeine	Confusion-Bewilderment	6.23	Standard Error 0.48	units on a scale
Mood State Score on POMS-2 Test	Placebo	Confusion-Bewilderment	7.00	Standard Error 0.53	units on a scale
Mood State Score on POMS-2 Test	Caffeine	Depression-Dejection	1.87	Standard Error 0.35	units on a scale
Mood State Score on POMS-2 Test	Placebo	Depression-Dejection	3.15	Standard Error 0.61	units on a scale
Mood State Score on POMS-2 Test	Caffeine	Fatigue-Inertia	4.44	Standard Error 0.49	units on a scale
Mood State Score on POMS-2 Test	Placebo	Fatigue-Inertia	6.65	Standard Error 0.68	units on a scale

1 to 10 of 24Source ClinicalTrials.gov

See all 24 results by group

Participant flow6

How many started, completed or left each group, period by period.

Period	Milestone	Group	Participants
Overall Study	STARTED	Caffeine	103
Overall Study	STARTED	Placebo	102
Overall Study	COMPLETED	Caffeine	103
Overall Study	COMPLETED	Placebo	102
Overall Study	NOT COMPLETED	Caffeine	0
Overall Study	NOT COMPLETED	Placebo	0

Source ClinicalTrials.gov

Adverse events0

Each adverse event the trial posted, group by group: the participants affected out of those at risk.

None in this release.

Adverse event totals6

The totals the trial posted for each group.

Total	Group	Affected	At risk
Total, all-cause mortality	Caffeine
Total, all-cause mortality	Placebo
Total, other adverse events	Caffeine	0	103
Total, other adverse events	Placebo	0	102
Total, serious adverse events	Caffeine	0	103
Total, serious adverse events	Placebo	0	102

Source ClinicalTrials.gov

Papers1

The papers the trial lists on ClinicalTrials.gov.

PMID	Listed as
28406674	RESULT

Source PubMed

Grants0

The grants NIH RePORTER links to the trial, newest funded first: NIH's, and some of AHRQ's, CDC's, FDA's and VA's. Each shows its title, principal investigators, organization and funder in its newest year.

None in this release.

Trial comparisons1

Comparisons of the trial's two groups, calculated by ConductScience from the counts it posted.

Comparison
Caffeine vs Placebo: serious adverse events

Source Trial comparisons

Tests0

The ConductCognition tests this trial's registered outcomes name, as ScienceGraph matched them in trial-tests-2026-11-12-0.2.1.

None in this release.

Data dates

The day each source was copied for this release.

ClinicalTrials.gov: 2026-11-12; ClinicalTrials.gov
Results, from AACT: 2026-03-23; AACT
NIH grant links: 2026-11-13; NIH RePORTER

Sources 3

ClinicalTrials.gov's posted results, through CTTI's AACTFreely available. Acknowledgement requested
ClinicalTrials.govNo license stated
NIH RePORTER's clinical studies and project filesPublic domain

Each source's terms

ClinicalTrials.gov's posted results, through CTTI's AACTClinicalTrials.gov data via Aggregate Analysis of ClinicalTrials.gov (AACT), CTTI. CTTI makes its materials freely available and requests acknowledgement. https://aact.ctti-clinicaltrials.org/documentation/299
ClinicalTrials.govnone stated
NIH RePORTER's clinical studies and project filesPublic domain (NIH RePORTER)

ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.

For software

Read this trial from software.

The record and each of its lists are JSON, twenty rows a page. No key.

GET https://conductscience.org/api/trials/v1/NCT02461693

GET https://conductscience.org/api/trials/v1/NCT02461693/results?page=2

API reference For AI assistants