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Completed

NCT Number: NCT03694886

The Effect of Tablet Size on Cognitive Performance Caffeine

This study aims to assess if tablet size, due to placebo effect, alters participants' performance on cognitive tests after consuming caffeine. Participants will be randomly assigned to one of four groups: 1) 90 mg caffeine with a 1 mm diameter sucrose pillule; 2) no caffeine with the small sucrose pillule; 3) 90 mg caffeine with a 5 mm sucrose pillule; 4) no caffeine with the large sucrose pillule.

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Key information

Conditions

Placebo Effect

Age range

18 year–40 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 4

Primary location

University of Colorado Denver

Denver, Colorado, 80204, United States

About this study

Background: A capsule's physical design (e.g. shape, size, and color) affects individuals' perception of drug efficacy; that is, how well a drug is likely to work. The goal of this study is to assess the effects tablet size may have on participant's performance on cognitive testing since research has found differences between preparation methods. Method: 120 participants will be randomly assigned to one of four groups: 1) 90 mg caffeine with a 1 mm diameter sucrose pillule; 2) no caffeine with the small sucrose pillule; 3) 90 mg caffeine with a 5 mm sucrose pillule; 4) no caffeine with the large sucrose pillule. Participants will consume the designated placebo tablet with water (caffeinated or non-caffeinated); then, participants will provide weekly caffeine intake and complete the neutral portion of Velten's Mood Induction Procedure until 30 minutes have passed to allow for caffeine activation. Participants will complete the Stroop test, Trial Making Tests A and B, and the Rey Auditory Verbal Learning Test. Previous literature, as far as the author knows, relied on evaluating drug efficacy based on appearance alone. This study aims to assess if tablet size, due to placebo effect, alters participants' performance on cognitive tests after consuming caffeine.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Fluent in written and spoken English
  • Ability to see color
  • No uncontrolled high blood pressure
  • No allergies to caffeine or sucrose
  • No history of heart disease
  • No untreated anxiety or depression
  • Non-pregnant
  • No caffeine consumed the day of participation

Exclusion criteria

  • Not fluent in written and/or spoken English
  • Uncontrolled high blood pressure
  • Color-blindness
  • Allergies to caffeine and/or sucrose
  • History of heart disease
  • Untreated anxiety or depression
  • Pregnant
  • Consumed caffeine on the day of participation

Treatment and study plan

Caffeine Anhydrous with small sucrose pill

Drug

caffeine anhydrous that has been weighed out to 90 mg per dose presented with a 1 mm sucrose pillule

Other names: pure caffeine powder

Placebo - large sucrose pill

Other

sucrose pillules of 5 mm diameter will be given to all participants in the large pill groups

Other names: sugar pill

Caffeine Anhydrous with large sucrose pill

Drug

caffeine anhydrous that has been weighed out to 90 mg per dose presented with a 5 mm sucrose pillule

Other names: pure caffeine powder

Placebo - small sucrose pill

Other

sucrose pillules of 1 mm diameter will be given to all participants in the small pill groups

Other names: sugar pill

Primary outcomes

  1. Stroop Color test

    Time frame: Within 90 minutes of receiving informed consent. Actual task time: approximately 1.5 minutes

    Measures processing speed. 100-item, time-trial task where participants read the color of printed items on the task paper as quickly as possible for 45 seconds. Scores are measured in the number of correct responses within the allotted time.

  2. Stroop Word test

    Time frame: Within 90 minutes of receiving informed consent. Actual task time: approximately 1.5 minutes

    Measures processing speed. 100-item, time-trial task where participants read color names printed on the task paper as quickly as possible for 45 seconds. Scores are measured in the number of correct responses within the allotted time.

  3. Trail Making task A

    Time frame: Within 90 minutes of receiving informed consent. Actual task time: approximately 2 minutes

    Measures processing speed. 25 item, time-trial task where participants must connect numbers in order as quickly as possible. Scores are measured by the amount of time (in seconds) for participants to complete the task.

Secondary outcomes

  1. Stroop Color-and-Word test

    Time frame: Within 90 minutes of receiving informed consent. Actual task time: approximately 2 minutes

    Measures processing speed. 100-item, time-trial task where participants must read the color of the ink instead of color names printed on the task paper as quickly as possible for 45 seconds. Scores are measured in the number of correct responses within the allotted time.

  2. Trail Making task B

    Time frame: Within 90 minutes of receiving informed consent. Actual task time: approximately 3 minutes

    Measures processing speed. 25 item, time-trial task where participants must connect numbers and letters in order (e.g. 1-A-2-B, etc.) as quickly as possible. Scores are measured by the amount of time (in seconds) for participants to complete the task.

  3. Rey Auditory Verbal Learning test

    Time frame: Within 90 minutes of receiving informed consent. Actual task time: approximately 40 minutes

    Measures memory. 30-item, 2 section task where participants are read 15 words and asked to recall as many words as possible in the first section. A second set of 15 words is then introduced and participants recall those. The second section consists of revisiting the original set of words and recalling as many of those. Scores are measured by the total words remembered in section one, and another score for the total intrusions from the second list into the recall of section two.

Sponsors and collaborators

Lead sponsor

University of Colorado, Denver

Other

Registry information

Official study title

The Effect of Tablet Size on Cognitive Performance: A Randomized Control Trial Using Caffeine

Acronym: CaC

Important dates

Study start
2018
Primary completion
2019
Study completion
2019
First posted
Oct 3, 2018
Registry last updated
Apr 17, 2019

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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