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

NCT02461693 | Completed Results

• 1 other identifier: F150410009
• Study Type: interventional
• Target: 205
• Locations: 0 countries
• Sites: N/A

Brief Summary

The purpose of this project is to examine the effect of expectancy on mood and alertness after consumption of caffeine "treatment" or placebo "control" pill, given that participants know their probability for receiving the caffeine versus placebo pill. Participants will be randomly assigned a probability (ranging from 0-100%) of receiving caffeine vs. placebo, and this probability will be revealed to them before consumption of the assigned pill and subsequent cognitive testing. At the time of consumption, neither study staff administering the intervention nor participants will know for certain which pill is given to each participant. Pill assignment will depend on pre-determined randomization probabilities, which will be provided and assigned by the study statistician. By revealing participants' individual probability of receiving the caffeine pill, we will induce positive or negative expectancies regarding likelihood for receipt of the caffeine pill. These experimental manipulations will: 1) estimate the effect of expectancy on cognitive and affective outcomes, and 2) allow for a more direct estimate of the effect of the caffeine pill under real-world conditions than would a conventional randomized trial.

Conditions

Caffeine; Affect; Cognitive Ability, General; Mood

Keywords

Vigilance; Mood; Randomized Controlled Trial; Probability

Outcome Measures

Primary Outcomes (4)

• Mood State Score on POMS-2 Test

  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.

  30 minutes post pill consumption

• Vigilance Score on Computer-based Test Using Random, Visual Stimulus: Proportion Correct (Out of 60)

  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

  45 to 105 minutes post pill consumption

• Vigilance Score on Computer-based Test Using Random, Visual Stimulus: Number Correct, Number of False Alarm Hits

  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

  45 to 105 minutes post pill consumption

• Vigilance Score on Computer-based Test Using Random, Visual Stimulus: Mean Time to a Correct Hit

  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

  45 to 105 minutes post pill consumption

Study Arms (2)

Caffeine

EXPERIMENTAL

One-time treatment with 200mg caffeine pill

Drug: Caffeine

Placebo

PLACEBO COMPARATOR

One-time treatment with lactose-based placebo pill

Drug: Placebo

Interventions

Caffeine DRUG

200mg delivered as pill; one-time dose

Caffeine

Placebo DRUG

Lactose-based pill; one-time dose

Placebo

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• years-old or older
• available to participate on the dates specified
• willing to take a caffeine or placebo pills at study session
• willingness to abstain from caffeine for 12 hours prior to study visit (8:30pm-8:30am)
• UAB employees or students with some college education (including current enrollment)

You may not qualify if:

• self-reported use of ADHD medication
• self-reported use of anxiety medication
• self-reported use of sleep medication
• self-reported use of nicotine products
• self-reported lactose intolerance
• self-reported uncorrected vision
• self-reported pregnancy or trying to become pregnant

Sponsors & Collaborators

• University of Alabama at Birmingham: lead

Related Publications (1)

• George BJ, Li P, Lieberman HR, Pavela G, Brown AW, Fontaine KR, Jeansonne MM, Dutton GR, Idigo AJ, Parman MA, Rubin DB, Allison DB. Randomization to randomization probability: Estimating treatment effects under actual conditions of use. Psychol Methods. 2018 Jun;23(2):337-350. doi: 10.1037/met0000138. Epub 2017 Apr 13.

  PMID: 28406674 RESULT

MeSH Terms

Interventions

Caffeine

Intervention Hierarchy (Ancestors)

Xanthines; Alkaloids; Heterocyclic Compounds; Purinones; Purines; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring

Limitations and Caveats

Please refer to our publication in Psyhcological Methods

Results Point of Contact

• Title: Dr. David Allison, PI
• Organization: University of Alabama at Birmingham

dallison@uab.edu

205-975-9169

Study Officials

• David B Allison, PhD

  University of Alabama at Birmingham

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: Yes

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Masking Details: Participants, study personnel interacting with participants, and investigators were blinded. Only the study statistician knew treatment assignments.
• Purpose: OTHER
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Dean for Science, School of Public Health

Study Record Dates

• First Submitted: June 1, 2015
• First Posted: June 3, 2015
• Study Start: June 1, 2015
• Primary Completion: October 1, 2015
• Study Completion: October 1, 2015
• Last Updated: July 12, 2017
• Results First Posted: July 12, 2017

Record last verified: 2017-06

Data Sharing

• IPD Sharing: Will share