Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT06038903 |
| Other study ID # |
EskisehirTU-SBF-CK-02 |
| Secondary ID |
|
| Status |
Completed |
| Phase |
|
| First received |
|
| Last updated |
|
| Start date |
September 8, 2023 |
| Est. completion date |
October 15, 2023 |
Study information
| Verified date |
February 2024 |
| Source |
Eskisehir Technical University |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Observational [Patient Registry]
|
Clinical Trial Summary
Caffeine is a psycho-active substance that is widely consumed in the world. It is seen that
its widespread consumption is related to expectancies of consumption as well as cultural
factors. Recreationally active individuals may have various expectations from caffeine
consumption in line with their lifestyles and goals such as physical, social and/or other
aspects. It can be stated that caffeine consumption expectancies have an important role in
the process of evaluating consumption patterns. However, in the literature it seems to be
very limited information about expectancies related to caffeine consumption. In this
direction, the aim of the research was to test the compatibility of Brief-Caffeine Expectancy
Questionnaire (B-CaffeQ) to Turkish culture and language. In the study, data will be
collected from two separate participant groups and going to analysis. To reveal the structure
on the first group (n=250-300 approx.) data, Exploratory Factor Analysis (EFA), and to verify
the structure on the second group (n=313) data, Confirmatory Factor Analysis (CFA) will be
used. Reliability will be assessed by performing test-retest and internal consistency
analyzes on both the two data groups.
Description:
INTRODUCTION
Caffeine (1,3,7-trimethylxanthine) is most commonly found in coffee as the main
pharmacologically active ingredient. In general, brewed coffee has the highest content among
foodstuffs containing caffeine. Coffee (230-250ml), depending on the preparation method, the
type of beans, roasting, grinding type and brand, contains 35-250 mg of caffeine while tea
(150 ml) 24-50 mg, cola drinks (180 ml) 15-30 mg, cocoa (150 ml) 2-7 mg, chocolate (28 g)
1-36 mg, and the foods containing chocolate mostly contain less than 15 mg caffeine.
Doses of up to 300-400mg per day in healthy adults (19 and over) are specified as safe upper
limit without any harmful effects. This amount corresponds to 4-5 cups of medium coffee.
However, it is stated that caffeine consumption equal to 6 cups of dark coffee generally does
not cause any side effects. It is stated that the daily limit for adolescents and children is
100 mg and this limit should not be exceeded. However, coffee is not the only source of
caffeine, and other sources caffeine consumed should also be taken into account.
The average daily caffeine consumption in Turkey for adolescents and children aged 15 and
below is an average of 197 mg and 202 mg for 18 and older. The source of caffeine for
adolescents is mostly tea, carbonated soft drinks and instant coffee consumption. Average
daily caffeine consumption in adult working individuals is 247 mg, and this is due to the
consumption of carbonated soft drinks, chocolate, instant coffee, respectively. It is seen
that 20% of university students who consume caffeine have an average daily consumption of 250
mg and above, and this mostly due to the consumption of tea, coffee, Turkish coffee,
carbonated soft drinks and chocolate. In USA, while the main source of caffeine is coffee for
the age of 18 and above, it is caffeine-containing soft drinks for the age of 2-17.
There is evidence that some individuals' expectancies of caffeine's effects on physical
performance and mood may affect the magnitude of these effects. There are studies showing
that caffeine anticipation effect affects mood, attention, and vitality. In the case of
caffeine expectancy, placebo administration stimulates changes in the dopaminergic system in
the brain. The neurobiological mechanisms of caffeine and placebo caffeine were similar in
the brain, but somewhat more limited in placebo caffeine. It is stated that the expectancy of
the individual may manage the placebo effect and accordingly, the expected effect of caffeine
or the drug consumed may change the response to placebo. Beyond the pharmacological effects
of a drug, an individual's expectancies of it may also contribute to the intensive
experiences of the drug in question. The fact that individuals who are told they had
decaffeinated coffee but are given caffeine perform worse than those who do not consume
caffeine, support the view that the pharmacological effects of caffeine act synergistically
with anticipation. In addition, it has been stated that the effects caused by caffeine
withdrawal may also be caused by the negative expectancies (nosebo) of an individual. These
results provided evidence that the subjective and behavioral effects of caffeine consumption
may be positive or negative depending on the individual's expectancies from caffeine. These
expectancies may arise from the individual's previous experiences with caffeine. The effects
of caffeine depend on the individual's expectancies, so if the individual consumes a beverage
expecting that it has caffeine in it, these expectancies may be generalized as placebo
conditions. In placebo studies, it is stated that one of the factors that cause an individual
to respond to a treatment may be caused by the type of individual who may respond to
treatment via expectancies. In other words, this view is not specific to the treatment of the
practice applied, rather that the response may be shaped according to the expectancies of the
individual, that expectancies may cause a placebo (or nosebo) effect. When there is
confidence in the drug effect of a drug in a particular activity, an expectancy of a specific
behavioral effect of that drug may also be formed. Based on expectancies about the effects of
caffeine, the behavioral response to this drug derivative can be predicted. However, this
expectancy theory is insufficient to explain the fact that some individuals without
expectancies not showing stimulating effects when they consume caffeine for the first time.
There are other studies which do not observe expectancy affects in caffeine consumption,
suggesting placebo and expectancy effects are caused by introspection. The results showed
that both pharmacological and expectancy factors affect the actual and expectancy effects of
caffeine in an individual's behaviour.
Some of the performance enhancing effects of caffeine appear to be linked to expectancies.
Since the bitter taste of caffeine may act as a signal that caffeine has been consumed, it
seems possible that some anticipatory effects of caffeine consumption may be driven by this
bitter taste. It is said that consuming 300-400 mg caffeine a day, equivalent of 3-4 cups of
coffee daily, may have positive effects on the well-being of an individual and may partially
improve mental-physical disorders. Performance increases were also observed with individuals
who consume coffee regularly when they are given decaffeinated coffee. This suggests a
caffeine related stimulus causes a caffeine related effect. This result also indicates, other
features of coffee such as its smell and taste rather than caffeine itself, may also be
effective in the development of these expectancies. It has been observed when these
individuals who consume coffee regularly do not wish to consume caffeine yet want to benefit
from its performance enhancement effects, decaffeinated coffee also creates a good effect on
performance enhancement. In addition, the expectancy for the positive effects of caffeine
consumption is an indicator of how much and how often caffeine will be consumed.
PURPOSE OF RESEARCH Since caffeine consumption is rather widespread in Turkey, it can be seen
that an instrument to be used in research on caffeine consumption expectancies such as
caffeine expectancy survey is needed. Accordingly, the purpose of this research is to adapt
and verify the Breif-Caffeine Expectancy Questionnaire (B-CaffeQ) which has been developed by
Kearns et al. (2018) and consists of seven dimensions: withdrawal / dependence, energy / work
enhancement, appetite suppression, social / mood enhancement, physical performance
enhancement, anxiety / negative physical effects, and sleep disturbance, to Turkish culture
and language.
METHODOLOGY Research model
This research model includes a methodological process in which the Brief-Caffeine Expectancy
Questionnaire is evaluated through the validity and reliability analysis of the Turkish
language and culture. This process includes some steps will be deemed necessary for the
adaptation of the questionnaire. These stages will be followed in the following order:
- Survey translation.
- Evaluating the items and making the necessary corrections.
- Testing the items.
- Creating the initial form of the questionnaire.
- Implementation of the survey.
- Conducting analyses.
- Finalizing the questionnaire.
- Examination of the measurement model.
- Reporting of the process.
Research group The participants in this study are recreationally active individuals. Data
will be collected from two different groups for validity and reliability assessments. Data
will be obtained from the first group, in which the processes related to Exploratory Factor
Analysis (EFA) will be carried out, and the processes related to Confirmatory Factor Analysis
(CFA) will carry out with the data collected from the second group. Groups consist of
participants will select by the purposive sampling. For the purpose of this research,
individuals who consume products containing caffeine such as coffee, tea, and soft drinks
constitute the research group. Accordingly, data will collect from 250-300 (aprroximately)
participants for EFA process and from 30 participants for CFA process.
Ethical clearance The study protocol was approved by the Scientific Research and Publishing
Ethics Committee of Eskisehir Technical University (Decree number:
E-87914409-050.03.04-8971).
Data collection tool and technique During the data collection phase, a questionnaire form
consisting of three parts will use. In the first part, explanations about the research and
caffeine containing product information which the participant based their answers on
included. In the second part of the questionnaire, Brief-Caffeine Expectancy Questionnaire,
which is a simplified version of the caffeine expectancy questionnaire developed by Huntley
and Juliano, will be included. This questionnaire, whish has been simplified by Kearns et al.
(2018) by carrying out validity and reliability studies, has a 7-factor structure, consisting
of 20 articles. The rating of this questionnaire, which was created in six Likert type, was
defined as "1 = Strongly Disagree" to "6= Strongly Agree". In the last part of the
questionnaire, there will be questions from which the demographic information of the
participants such as age, gender, educational status, etc. obtain.
Aforementioned questionnaire form will be prepared on an online platform and the connection
link will be provided. This link will be conveyed to participants through posts shared on
these social media accounts.
Language equivalence In the process of adapting B-CaffeQ to Turkish language and culture,
back translation method will be used in order to provide language equivalence. Accordingly,
both the English to Turkish and Turkish to English translations will made independently by
two different linguists who are adept in both languages and cultures. Finally, the articles
will translate back into English and compare with their original forms.
Data analysis EFA will use in order to determine what kind of a structure pattern the survey
constitutes in Turkish language and culture. CFA will use to test the accuracy of the
structure resulting from EFA. Reliability tests of the questionnaire will perform through
Cronbach Alpha coefficient and test-retest analysis.
