Evaluating the Role of Expectations in Response to Caffeine Consumption: An RCT
2017年6月13日 更新者：David Allison, Phd、University of Alabama at Birmingham
Evaluating the Role of Expectations in Response to Caffeine Consumption: A Randomized Control Trial
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.
調査の概要
研究の種類
介入
入学 (実際)
205
段階
- 適用できない
参加基準
研究者は、適格基準と呼ばれる特定の説明に適合する人を探します。これらの基準のいくつかの例は、人の一般的な健康状態または以前の治療です。
適格基準
就学可能な年齢
18年歳以上 (大人、高齢者)
健康ボランティアの受け入れ
いいえ
受講資格のある性別
全て
説明
Inclusion Criteria:
- 18 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)
Exclusion Criteria:
- 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
研究計画
このセクションでは、研究がどのように設計され、研究が何を測定しているかなど、研究計画の詳細を提供します。
研究はどのように設計されていますか？
デザインの詳細
- 主な目的：他の
- 割り当て：ランダム化
- 介入モデル：並列代入
- マスキング：ダブル
武器と介入
参加者グループ / アーム |
介入・治療 |
|---|---|
|
実験的：Caffeine
One-time treatment with 200mg caffeine pill
|
200mg delivered as pill; one-time dose
|
|
プラセボコンパレーター：Placebo
One-time treatment with lactose-based placebo pill
|
Lactose-based pill; one-time dose
|
この研究は何を測定していますか？
主要な結果の測定
結果測定 |
メジャーの説明 |
時間枠 |
|---|---|---|
|
Mood State Score on POMS-2 Test
時間枠：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.
|
30 minutes post pill consumption
|
|
Vigilance Score on Computer-based Test Using Random, Visual Stimulus: Proportion Correct (Out of 60)
時間枠：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
|
45 to 105 minutes post pill consumption
|
|
Vigilance Score on Computer-based Test Using Random, Visual Stimulus: Number Correct, Number of False Alarm Hits
時間枠：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
|
45 to 105 minutes post pill consumption
|
|
Vigilance Score on Computer-based Test Using Random, Visual Stimulus: Mean Time to a Correct Hit
時間枠：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
|
45 to 105 minutes post pill consumption
|
協力者と研究者
ここでは、この調査に関係する人々や組織を見つけることができます。
捜査官
- 主任研究者：David B Allison, PhD、University of Alabama at Birmingham
出版物と役立つリンク
研究に関する情報を入力する責任者は、自発的にこれらの出版物を提供します。これらは、研究に関連するあらゆるものに関するものである可能性があります。
研究記録日
これらの日付は、ClinicalTrials.gov への研究記録と要約結果の提出の進捗状況を追跡します。研究記録と報告された結果は、国立医学図書館 (NLM) によって審査され、公開 Web サイトに掲載される前に、特定の品質管理基準を満たしていることが確認されます。
主要日程の研究
研究開始
2015年6月1日
一次修了 (実際)
2015年10月1日
研究の完了 (実際)
2015年10月1日
試験登録日
最初に提出
2015年6月1日
QC基準を満たした最初の提出物
2015年6月2日
最初の投稿 (見積もり)
2015年6月3日
学習記録の更新
投稿された最後の更新 (実際)
2017年7月12日
QC基準を満たした最後の更新が送信されました
2017年6月13日
最終確認日
2017年6月1日
詳しくは
本研究に関する用語
キーワード
追加の関連 MeSH 用語
その他の研究ID番号
- F150410009
個々の参加者データ (IPD) の計画
個々の参加者データ (IPD) を共有する予定はありますか?
はい
IPD プランの説明
Raw de-identified data will be posted as a replication data set on ICPSR after publication of results in a journal.
Data will be free to download and accessible to anyone with access to ICPSR replication data sets.
医薬品およびデバイス情報、研究文書
米国FDA規制機器製品の研究
いいえ
米国で製造され、米国から輸出された製品。
いいえ
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