# OToPS/Measures/Big Five Inventory
## Lead section

The Big Five Inventory (BFI) is a 44 item self-report questionnaire, developed by John and researchers, that measures an individual on the five personality factors from the Big Five, or the five factor model (FFM), with each item being rated on a five point scale. The following factors that also make up the subscales of the BFI are: Extraversion, Agreeableness, Conscientiousness, Neuroticism, and Openness. The BFI is one of the most commonly used tool for assessing individual personality traits and can be used across a variety of settings, either for personal use or for clinical or research purposes. The BFI is also known to be a reliable and valid measure of the Big Five personality traits, while keeping the completion time to be efficient (takes about 5 - 15 minutes to administer). The BFI is typically administered in older populations, but younger populations can fill out this measure as well. In addition, the BFI is available in different languages.

## Reliability
### Instrument rubric table: Reliability

Note: Not all of the different types of reliability apply to the way that questionnaires are typically used. Internal consistency (whether all of the items measure the same construct) is not usually reported in studies of questionnaires; nor is inter-rater reliability (which would measure how similar peoples' responses were if the interviews were repeated again, or different raters listened to the same interview). Therefore, make adjustments as needed.
Click here for instrument reliability table :
Reliability
Not all of the different types of reliability apply to the way that questionnaires are typically used. Internal consistency (whether all of the items measure the same construct) is not usually reported in studies of questionnaires; nor is inter-rater reliability (which would measure how similar peoples' responses were if the interviews were repeated again, or different raters listened to the same interview). Therefore, make adjustments as needed.
Reliability refers to whether the scores are reproducible. Unless otherwise specified, the reliability scores and values come from studies done with a United States population sample. Here is the rubric for evaluating the reliability of scores on a measure for the purpose of evidence based assessment.
Evaluation for norms and reliability for the Big Five Inventory (table from Youngstrom et al., extending Hunsley & Mash, 2008; *indicates new construct or category)
CriterionRating (adequate, good, excellent, too good*)Explanation with references
NormsAdequateResearch of the BFI includes mostly convenience samples and samples taken from surveys from other research projects. In addition, the sample sizes were quite large for most of the studies that were evaluating the psychometrics of the BFI. These samples mainly came from nonclinical populations.
Internal consistency (Cronbach’s alpha, split half, etc.)GoodCronbach's alphas typically ranged from .75 to .90 for subscales and average above .80.[citation needed]
Interrater reliabilityNot applicableThe BFI is designed to be a self-report scale; therefore, inter-rater reliability does not apply here.
Test-retest reliability (stabilityGoodReliability correlations ranged from .80 to .90 for a 3 month retest. Other studies found that 2 month retest reliability correlations were greater than .75., with data also show high stability in clinical trials[citation needed]
RepeatabilityNot publishedNo studies have been published that evaluates the repeatability of the BFI. :

### Instrument rubric table: Validity

Click here for instrument validity table :
Validity
Validity describes the evidence that an assessment tool measures what it was supposed to measure. There are many different ways of checking validity. For screening measures, diagnostic accuracy and w:discriminative validity are probably the most useful ways of looking at validity. Unless otherwise specified, the validity scores and values come from studies done with a United States population sample. Here is a rubric for describing validity of test scores in the context of evidence-based assessment.
Evaluation of validity and utility for the Big Five Inventory (table from Youngstrom et al., unpublished, extended from Hunsley & Mash, 2008; *indicates new construct or category)
CriterionRating (adequate, good, excellent, too good*)Explanation with references
Content validityExcellentThe BFI has been thoroughly developed by the primary researchers. Multiple studies have determined that the facets and domains in the BFI accurately represent the theoretical construct.
Contruct validity (e.g., predictive, concurrent, convergent, and discriminant validity)ExcellentThe BFI shows convergent validity with other well-known personality measures of the Big Five. Studies have shown that the factor structure was highly stable across different phases of the life span after analyzing the convergence of the BFI factor solutions across different age groups. Construct reliabilities averaged .85 on BFI factors. Correlations between BFI scores, self-esteem, social desirability, and optimism were in the low to moderate range, indicating that the BFI is a well-defined, independent measure., criterion validity via metabolic markers and associations with family history of mood disorder.
Discriminative validityExcellentStudies have found that there were low discriminant correlations for the BFI, showing evidence for validity.
Validity generalizationGoodThe BFI is used mainly as a self-report. College students as well as other older populations can freely access and use the BFI for personal or research use. The BFI has multiple shortened, revised, and translated versions, all of which have good reliability and validity. as well as outpatient and inpatient clinical samples; translated into multiple languages with good reliability
Treatment sensitivityNot publishedStudies have not been published to address treatment sensitivity of the BFI.
Clinical utilityAdequateThe BFI can be freely accessed online. Strong psychometrics and evidence supported research shows that it can be utilized. :

## Development and history

Previously, researchers have attempted to identify the major dimensions of personality. Researchers defined many facets and factors of personality; however, there were complications with their theoretical models. Tupes and Christal eventually have found five strong factors of personality. Initially, there were known as Extraversion or Surgency, Agreeableness, Conscientiousness, Emotional Stability versus Neuroticism, and Culture. These later became known as the Big Five. These five factors allow for a broader framework that contains and categorizes more specific personality traits.
One of the first attempts to include the Big Five in questionnaires was made by Costa and McCrae, as they were developing the NEO Personality Inventory that included factors of Neuroticism, Extraversion, and Openness, and later included Agreeableness and Conscientiousness factors (with the revised NEO Personality Inventory, NEO PI-R). However, these previous measures of the big five personality traits often take too long to complete. Researchers (John, Donahue, and Kentle) wanted to address the need for short instruments measuring components of the Big Five by developing a brief inventory that would allow efficient and flexible assessment of the five dimensions. The items in the BFI were developed through factor analytic verification in personality ratings. The items of BFI comprise of short phrases based on trait adjectives known to be markers of the Big Five, instead of including just one adjective. This structure was kept so as to avoid ambiguity and to still keep the measure brief. These short scales save testing time and also avoid boredom and fatigue of the test-takers.
The Big Five Inventory is composed of the following subscales:
Extraversion
Neuroticism
Conscientiousness
Openness
Agreeableness

## Impact

The major goal for the Big Five Inventory was to be a brief and reliable personality measure than other previous personality measures. It is not only easy to administer, but it also takes a very short amount of time to complete, as it takes about 5 - 15 minutes. In addition, it can be used in multiple settings, for personal use or for research purposes, and it is also available online.

## Use in other populations
### Versions:
#### Revised version of the BFI

Researchers have recently developed a revised version of the BFI, known as the BFI-2. The BFI-2 has 60 items. The BFI-2 is aimed to be an improvement of the original BFI and has higher predictive power as well as better reliability and validity scores.

#### Shortened versions

There are many different versions of the BFI. The BFI has been condensed to various short versions, most of which are reduced to five to ten items. These shorter measures have been shown to have adequate reliability and validity scores, while trying to aim for brevity.

#### Translated BFI

The BFI has also been released and translated to different languages other than English: Chinese, Dutch, German, Hebrew, Italian, Lithuanian, Portuguese, Spanish, and Swedish. Research has supported that these translated versions also have good reliability and validity.

## Limitations

The BFI is a self report measure, which have some vulnerabilities in its experimental design. For instance, social desirability bias in participant can occur, as individuals can rate themselves on personality traits in a way that portrays them more positively. This type of bias can skew the accuracy of the results. In addition, since this is a subjective measure, it may be difficult for the individuals to precisely pinpoint a number that represents how likely it is that the description best suits them. Moreover, the answers that they give might not accurately represent who they are. Because the BFI was intended to be a short scale, this can lead to some drawbacks, as including lesser items could sacrifice reliability and validity scores.

## Scoring instructions and syntax

We have syntax in three major languages: R, SPSS, and SAS. All variable names are the same across all three, and all match the CSV shell that we provide as well as the Qualtrics export.

### Hand scoring and general instructions

The following questions on the BFI are reversed scored:
Extraversion: 6, 21, 31
Agreeableness: 2, 12, 27, 37
Conscientiousness: 8, 18, 23, 43
Neuroticism: 9, 24, 34
Openness: 35, 41
To reverse-scored these items, subtract the answer that was given from 6. 1 becomes a 5, 2 becomes 4, 3 is still 3, 4 becomes 2, and 5 becomes 1. To create scale scores, you will add the total responses for each subscale (R represents the reverse-scored item) and then average them.
Extraversion: 1, 6R, 11, 16, 21R, 26, 31R, 36
Agreeableness: 2R, 7, 12R, 17, 22, 27R, 32, 37R, 42
Conscientiousness: 3, 8R, 13, 18R, 23R, 29, 33, 38, 43R
Neuroticism: 4, 9R, 14, 19, 24R, 29, 34R, 39
Openness: 5, 10, 15, 20, 25, 30 35R, 40, 41R, 44

### CSV shell for sharing

Here is a shell data file that you could use in your own research. The variable names in the shell corresponds with the scoring code in the code for all three statistical programs.
Note that our CSV includes several demographic variables, which follow current conventions in most developmental and clinical psychology journals. You may want to modify them, depending on where you are working. Also pay attention to the possibility of "deductive identification" -- if we ask personal information in enough detail, then it may be possible to figure out the identity of a participant based on a combination of variables.
When different research projects and groups use the same variable names and syntax, it makes it easier to share the data and work together on integrative data analyses or "mega" analyses (which are different and better than meta-analysis in that they are combining the raw data, versus working with summary descriptive statistics).