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The Internet Addiction Test (IAT) is the most widely used questionnaire to screen for problematic Internet use. Nevertheless, its factorial structure is still debated, which complicates comparisons among existing studies. Most previous studies were performed with students or community samples despite the probability of there being more problematic Internet use among users of specific applications, such as online gaming or gambling.
To assess the factorial structure of a modified version of the IAT that addresses specific applications, such as video games and online poker.
Two adult samples—one sample of Internet gamers (n=920) and one sample of online poker players (n=214)—were recruited and completed an online version of the modified IAT. Both samples were split into two subsamples. Two principal component analyses (PCAs) followed by two confirmatory factor analyses (CFAs) were run separately.
The results of principal component analysis indicated that a one-factor model fit the data well across both samples. In consideration of the weakness of some IAT items, a 17-item modified version of the IAT was proposed.
This study assessed, for the first time, the factorial structure of a modified version of an Internet-administered IAT on a sample of Internet gamers and a sample of online poker players. The scale seems appropriate for the assessment of such online behaviors. Further studies on the modified 17-item IAT version are needed.
As the main medium of modern life, the Internet is used in a wide range of human activities. This expansion has numerous benefits, including its use for social, psychological, and medical purposes, as shown by a wide range of studies on eHealth [
In recent years, several studies proposed incorporating Internet addiction as a new diagnosis into the Diagnostic and Statistical Manual of Mental Disorders (DSM) [
With this potential new diagnosis, an important challenge is to develop assessment tools that are able to capture the specificity of this phenomenon, not only in terms of presence or absence of a given diagnostic, but also in terms of gradient severity. Since the initial research on Internet addiction, several psychometric measures have been developed [
Despite the large diffusion of the IAT for research purposes, there is wide disagreement related first, to its factor structure [
The issues related to the factorial structure of the IAT were possibly complicated by specific item-related concerns [
1. Item 4—“How often do you form new relationships with fellow online users?”—has problematic loadings in a number of studies [
2. Item 6—on consequences on school work—and Item 8—related to job performance—ask about similar fields. However, the answer may differ depending on the participant’s understanding and on the specific status of the participant. Unsurprisingly, covariance was repeatedly found between these items [
3. A similar type of overlap was shown between Item 3—“How often do you prefer the excitement of the Internet to intimacy with your partner?”—and Item 19—“How often do you choose to spend more time online over going out with others?” This lead some authors to discard one of the items [
4. In contrast with the other IAT components, Item 7—“How often do you check your email before something else that you need to do?”—is not related to the Internet in general, but to a specific use (ie, emails). Concerns were reported in a number of studies [
5. As a result of permanent Internet access (ie, without a specific need to log in), a rewording of Item 14 was proposed, as follows: “How often do you lose sleep due to being online late at night?” [
As shown, some of these IAT items involved specific patterns of life, such as being employed or being in a relationship. The “not applicable” answer option was probably included for this reason. It was, however, considered to be problematic by some authors [
In addition to conflicting results on the structure and certain items of the IAT, the psychometric characteristics were mostly assessed with students or community samples (
To our knowledge, no previous studies have assessed the psychometric characteristics of the instrument specifically for users of a given Internet application such as Internet games or gambling sites, despite the wide use of the scale, with or without modification, in studies related to these specific patterns of use [
In the context of increasing interest in possible Internet addiction-related disorders—with common involvement of gaming and gambling—and the emergence of the DSM-5 concept of the Internet gaming disorder, the use of a modified IAT for assessment of online gaming and online gambling may be worthwhile.
Moreover, the lack of published studies on the psychometrical properties of the IAT on samples of gamers or gamblers appears to be an important weakness. This is of particular importance considering the increasing resemblance between gambling and gaming [
The main goal of this study, therefore, was to investigate the factorial structure of the French version of the IAT modified for Internet gaming—or gambling—when used online, using samples of Internet gamers and Internet gamblers.
IAT items modified for Internet game use:
1. How often do you find that you stay in-game longer than you intended?
2. How often do you neglect household chores to spend more time in-game?
3. How often do you prefer the excitement of the game to intimacy with your partner?
4. How often do you form new relationships with fellow game users?
5. How often do others in your life complain to you about the amount of time you spend in-game?
6. How often do your grades or school work suffer because of the amount of time you spend in-game?
7. How often do you check your email before something else that you need to do?
8. How often does your job performance or productivity suffer because of the game?
9. How often do you become defensive or secretive when anyone asks you what you do in-game?
10. How often do you block out disturbing thoughts about your life with soothing thoughts about the game?
11. How often do you find yourself anticipating when you will go in-game again?
12. How often do you fear that life without the game would be boring, empty, and joyless?
13. How often do you snap, yell, or act annoyed if someone bothers you while you are in-game?
14. How often do you lose sleep due to late-night log-ins?
15. How often do you feel preoccupied with the game when offline, or fantasize about being in-game?
16. How often do you find yourself saying "just a few more minutes" when in-game?
17. How often do you try to cut down the amount of time you spend in-game and fail?
18. How often do you try to hide how long you've been in-game?
19. How often do you choose to spend more time in-game over going out with others?
20. How often do you feel depressed, moody, or nervous when you are offline, which goes away once you are back in-game?
Internet Addiction Test item correspondence with the Diagnostic and Statistical Manual of Mental Disorders, fifth edition, gaming and gambling disorders criteria.
Internet gaming disorder: proposed DSM-5 criteria | Gambling disorder: DSM-5 criteria |
Preoccupation with Internet games (11, 15)a | Preoccupation with gambling (11, 15) |
Withdrawal symptoms when Internet gaming is taken away (20) | Withdrawal (restless or irritable when attempt to cut down or stop gambling) (20) |
Tolerance (the need to spend increasing amounts of time engaged in Internet games)b | Tolerance (needs to gamble with an increasing amount of money)b |
Unsuccessful attempts to reduce or stop Internet game participation (1, 16, 17) | Unsuccessful attempts to reduce or stop gambling (1, 16, 17) |
Loss of interest in other activities (3, 7, 19) | N/Ac |
Continues excessive use of Internet games despite problems (2, 6, 8, 14) | N/A |
Deceives others regarding the amount of Internet gaming (5, 9, 13, 18) | Lies to conceal the importance of gambling involvement (9, 18) |
Use of Internet games to escape from adverse moods (10) | Escape (often gambles when feeling distressed) (10) |
Has jeopardized or lost relationships or opportunities due to excessive Internet gaming (8) | Has jeopardized or lost relationships or opportunities due to excessive gambling (8) |
N/A | Relies on others to provide money to relieve the financial situations caused by gamblingb |
N/A | After losing money gambling, often returns to get even (“chasing” one’s losses)b |
Number of criteria: 5 or more | Number of criteria: 4 or more |
Time criteria: 12 months or more | Time criteria: 12 months or more |
Exclusion criteria: Internet use not related to online games is not “analogous to Internet gaming disorder” | Exclusion criteria: The behavior is better explained by a manic episode |
aThe suggested IAT items from
bNot associated with an IAT item.
cNot applicable (N/A).
Two samples were used in this study: a French-speaking sample of World of Warcraft (WoW) players and a French-speaking sample of Internet poker players. These two samples completed the same modified version of the IAT. The ethical committee of the Department of Psychology of the University of Geneva—for the WoW sample—and the ethical committee of the Geneva University Hospitals—for the poker players sample—approved the study.
The WoW sample was taken from a larger study on the relationships between players’ self-reported motives to play and their in-game behaviors [
The poker players sample was taken from a study on online gambling. Inclusion criteria included playing online poker, speaking French, and being at least 18 years old. Participants were recruited through advertisements posted in dedicated French-language forums on online gambling or poker. All participants gave their online consent. The sample of poker players included 442 participants, of whom 214 (48.4%) completed the IAT. The mean age of IAT completers was 31.9 years (SD 9.5) and 425 of the 442 participants (96.2%) were men.
All participants—WoW gamers and poker players—completed the same modified IAT. The scale is a 20-item auto-questionnaire [
Because no clear factor structure has emerged in the literature and because different studies that found the same number of factors were inconsistent regarding factor loadings, we decided to assess the factor structure underlying this questionnaire from scratch (ie, without imposing a specific model or number of factors). In order to achieve this goal, both samples were randomly split into two subsamples of half of the size of the original ones (ie, 107 subjects for the poker sample and 460 for the WoW sample). Two principal component analyses (PCAs) were first performed on the first subsamples separately. With the discrete nature of the IAT items, PCA is preferred over factor analysis since PCA does not assume any particular multivariate model, which is not the case for factor analysis [
In a second step, two confirmatory factor analyses (CFAs) were conducted to validate the structure that emerged from the PCA. The CFAs were run on the second subsamples. For the same reasons that PCA was preferred, the unweighted least-square method was chosen as the procedure for estimation. Four preestablished criteria were selected as indicators of the goodness of fit to the data: (1) goodness-of-fit index >.90 [
The PCA was done with R 3.1.0, using
The MAP test and the scree test clearly suggested in both subsamples that one component be extracted. In order to evaluate the stability of the PCA, a bootstrap technique [
The percentage explained variance (95% CI) was 41.6 (31.6-51.1) for poker players and 36.1 (32.6-39.8) for WoW players. The reliability, as reported by Cronbach alpha (95% CI), was .92 (.88-.95) for poker players and .90 (.88-.92) for WoW players.
The 20-item Internet Addiction Test results from principal component analysis.
Items | Estimated factor loadings (95% bootstrap CI) | |
|
Poker players (n=107) | WoW players (n=460) |
1. How often do you find that you stay in-game longer than you intended? | .65 (.52-.75) | .49 (.38-.58) |
2. How often do you neglect household chores to spend more time in-game? | .67 (.54-.77) | .73 (.68-.77) |
3. How often do you prefer the excitement of the game to intimacy with your partner? | .71 (.54-.84) | .41 (.29-.52) |
4. How often do you form new relationships with fellow game users? | 0 (-.20 to .20) | .26 (.14-.37) |
5. How often do others in your life complain to you about the amount of time you spend in-game? | .73 (.59-.86) | .61 (.53-.67) |
6. How often do your grades or school work suffer because of the amount of time you spend in-game? | .29 (.04-.55) | .50 (.41-.59) |
7. How often do you check your email before something else that you need to do? | .60 (.35-.76) | .67 (.60-.73) |
8. How often does your job performance or productivity suffer because of the game? | .63 (.38-.80) | .66 (.57-.73) |
9. How often do you become defensive or secretive when anyone asks you what you do in-game? | .65 (.42-.82) | .52 (.42-.61) |
10. How often do you block out disturbing thoughts about your life with soothing thoughts about the game? | .72 (.57-.84) | .68 (.62-.74) |
11. How often do you find yourself anticipating when you will go in-game again? | .57 (.39-.71) | .69 (.64-.73) |
12. How often do you fear that life without the game would be boring, empty, and joyless? | .56 (.32-.73) | .64 (.54-.71) |
13. How often do you snap, yell, or act annoyed if someone bothers you while you are in-game? | .62 (.38-.77) | .63 (.55-.70) |
14. How often do you lose sleep due to late-night log-ins? | .68 (.48-.80) | .64 (.58-.69) |
15. How often do you feel preoccupied with the game when offline, or fantasize about being in-game? | .64 (.46-.77) | .69 (.62-.74) |
16. How often do you find yourself saying "just a few more minutes" when in-game? | .65 (.45-.78) | .57 (.50-.63) |
17. How often do you try to cut down the amount of time you spend in-game and fail? | .77 (.62-.87) | .52 (.41-.61) |
18. How often do you try to hide how long you've been in-game? | .80 (.64-.89) | .55 (.45-.63) |
19. How often do you choose to spend more time in-game over going out with others? | .69 (.53-.81) | .64 (.56-.71) |
20. How often do you feel depressed, moody, or nervous when you are offline, which goes away once you are back in-game? | .79 (.67-.86) | .72 (.64-.77) |
Cronbach alpha was above .90 in both subsamples, which was found to be excellent. It is worth noting that when Item 4 or Item 6 were removed, Cronbach alpha increased from .92 to .93 for poker players and from .90 to .91 for WoW players.
According to the cutoff defined above, all four goodness-of-fit indices were considered excellent in both subsamples (
Because some items had low loadings and some questions had more missing values than occurred in the rest of the questionnaire, we performed additional investigations. In particular, Question 4—“How often do you form new relationships with fellow game users?”—seemed somewhat outdated and thus no longer relevant. Moreover, it had a low loading and decreased Cronbach alpha. Therefore, we decided to remove it.
Since Question 6—“How often do your grades or school work suffer because of the amount of time you spend in-game?”—is more suitable for school-aged persons, whereas Question 8—“How often does your job performance or productivity suffer because of the game?”—is more adapted to adults, we decided to merge the two questions into one. This new question addresses the consequences for the participant’s principal occupation, either school or work, preventing the participant from omitting the answer because it is not applicable. For the same reasons, we also merged Question 3—“How often do you prefer the excitement of the game to intimacy with your partner?”—and Question 19—“How often do you choose to spend more time in-game over going out with others?”
These modifications led to a 17-item questionnaire. Despite the fact that this version had not been tested on new subjects, we performed the same analyses as we did for the original questionnaire—randomly split both samples into two subsamples, running MAP, PCA, and CFA—by using the data at hand. For the merged questions, we decided to create two new items as follows: use the maximum mark of the IAT Item 3 and Item 19, as well as of Item 6 and Item 8, for each participant when both questions have been answered, or use the mark of only a single answered question.
In accordance with these modifications, the WoW sample size of IAT completers increased from 920 to 942 subjects, and the French-speaking poker sample size increased from 214 to 232. As expected, the results with this new method of coding the questionnaire led to the same conclusions regarding the number of components to extract—the bootstrapped MAP test suggested retaining only one factor in 74.2% and 95.6% of the poker and the WoW subsamples, respectively—regarding the factorial solution with the benefit of avoiding low loadings (
The percentage explained variance (95% CI) was 48.4 (37.5-58.1) for poker players and 37.3 (33.4-41.0) for WoW players. The reliability, as reported by Cronbach alpha (95% CI), was .93 (.90-.96) for poker players and .89 (.87-.91) for WoW players.
Results from unweighted least-square confirmatory factor analysis.
Fit indices | Unweighted least squares | |||
|
Poker players | WoW players | ||
|
IAT20a (n=107) | IAT17b (n=116) | IAT20 (n=460) | IAT17 (n=471) |
Root-mean-square residual | .08 | .07 | .08 | .08 |
Goodness-of-fit index | .97 | .97 | .97 | .97 |
Adjusted goodness-of-fit index | .97 | .97 | .96 | .97 |
Normed-fit index | .96 | .96 | .95 | .96 |
aThe 20-item Internet Addiction Test (IAT20).
bThe 17-item Internet Addiction Test (IAT17).
The 17-item Internet Addiction Test results from principal component analysis.
Items | Estimated factor loadings (95% bootstrap CI) | |
|
Poker players (n=107) | WoW players (n=460) |
1. How often do you find that you stay in-game longer than you intended? | .63 (.49-.73) | .51 (.41-.60) |
2. How often do you neglect household chores to spend more time in-game? | .75 (.64-.84) | .70 (.65-.75) |
Item 3 plus Item 19 | .78 (.68-.86) | .64 (.57-.70) |
5. How often do others in your life complain to you about the amount of time you spend in-game? | .68 (.51-.79) | .54 (.47-.62) |
Item 6 plus Item 8 | .65 (.53-.75) | .64 (.56-.71) |
7. How often do you check your email before something else that you need to do? | .67 (.47-.79) | .69 (.62-.75) |
9. How often do you become defensive or secretive when anyone asks you what you do in-game? | .70 (.48-.82) | .46 (.35-.55) |
10. How often do you block out disturbing thoughts about your life with soothing thoughts about the game? | .76 (.60-.87) | .67 (.60-.73) |
11. How often do you find yourself anticipating when you will go in-game again? | .59 (.42-.72) | .68 (.63-.73) |
12. How often do you fear that life without the game would be boring, empty, and joyless? | .67 (.49-.80) | .59 (.49-.68) |
13. How often do you snap, yell, or act annoyed if someone bothers you while you are in-game? | .61 (.41-.76) | .57 (.48-.65) |
14. How often do you lose sleep due to late-night log-ins? | .63 (.43-.77) | .66 (.59-.71) |
15. How often do you feel preoccupied with the game when offline, or fantasize about being in-game? | .69 (.52-.80) | .67 (.61-.73) |
16. How often do you find yourself saying "just a few more minutes" when in-game? | .64 (.46-.76) | .55 (.47-.62) |
17. How often do you try to cut down the amount of time you spend in-game and fail? | .73 (.55-.85) | .50 (.39-.60) |
18. How often do you try to hide how long you've been in-game? | .79 (.63-.89) | .54 (.45-.62) |
20. How often do you feel depressed, moody, or nervous when you are offline, which goes away once you are back in-game? | .81 (.63-.88) | .69 (.63-.75) |
This study is the first to assess, to our knowledge, the psychometric characteristics, and specifically the factorial structure, of the IAT in online samples of WoW gamers and poker players. The main finding is that the one-factor model of the IAT has good psychometric properties and fits the data well in these samples.
In consideration to both the important discrepancies in the factorial solutions found in the previous studies on the IAT and the inconsistencies in the items included in a given factor in studies with a similar number of factors (
Although heterogeneous results were found regarding the one-factor solution in previously reported studies, it was considered the best factor solution, or as possibly an acceptable factor solution (
As suggested elsewhere [
The modified 17-item IAT scale proposed here (
The problematic loading of Item 4 was also reported in some studies [
The 17-item IAT scale (
As there is an absence of questions related to tolerance in the original IAT, it is then also the case for the proposed data-driven 17-item IAT. A further study may add questions specifically related to tolerance in order to assess the full range of symptoms proposed by the DSM-5 criteria for IGD.
The relatively good coverage of the 17-item IAT of the DSM-5 criteria for IGD is a possible advantage in comparison to other shorter forms of the IAT that lead, for example, to withdrawal of the escape-related item. Unsurprisingly, the 17-item IAT scale and the original IAT do not cover items related to the financial conflict-related items of the DSM-5 criteria for gambling disorder.
One of the strengths of this paper is related to the design of a 17-item IAT scale through a data-driven approach, rather than a priori choices.
Despite the possible lack of items linked to specific Internet use, it appears from this study that the original IAT and the 17-item IAT are interesting assessment tools for disorders related to excessive Internet use. In particular, the results assessed in this study add to the validity of IAT use with specific rewording, such as replacing “Internet” with “game.”
IAT items modified for the 17-item IAT (a time frame should be added to the top of the scale, such as “During the last year, how often….?”):
1. How often do you find that you stay in-game longer than you intended?
2. How often do you neglect household chores to spend more time in-game?
3. How often do you prefer the excitement of the game to intimacy with your partner, or to spend more time in-game over going out with others?
4. How often do others in your life complain to you about the amount of time you spend in-game?
5. How often do your grades or your school work, or your job performance or productivity suffer because of the amount of time you spend in-game?
6. How often do you check your emaila before something else that you need to do?
7. How often do you become defensive or secretive when anyone asks you what you do in-game?
8. How often do you block out disturbing thoughts about your life with soothing thoughts about the game?
9. How often do you find yourself anticipating when you will go in-game again?
10. How often do you fear that life without the game would be boring, empty, and joyless?
11. How often do you snap, yell, or act annoyed if someone bothers you while you are in-game?
12. How often do you lose sleep due to late-night log-ins?b
13. How often do you feel preoccupied with the game when offline, or fantasize about being in-game?
14. How often do you find yourself saying "just a few more minutes" when in-game?
15. How often do you try to cut down the amount of time you spend in-game and fail?
16. How often do you try to hide how long you've been in-game?
17. How often do you feel depressed, moody, or nervous when you are offline, which goes away once you are back in-game?
The main limitations of this study include the representativeness of self-selected samples [
Further studies may test the 17-item IAT among various samples in parallel with other psychopathological and Internet-related behavior assessments, including the use of the DSM-5 proposed criteria and other assessment tools, with possibly different or complementary coverage of the concept of Internet addiction [
Summary of previous studies on the Internet Addiction Test factorial structure.
confirmatory factor analysis
Diagnostic and Statistical Manual of Mental Disorders
Diagnostic and Statistical Manual of Mental Disorders, fifth edition
Internet Addiction Test
17-item Internet Addiction Test
20-item Internet Addiction Test
Internet gaming disorder
minimum average partial
not applicable
principal component analysis
World of Warcraft
None declared.