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Adolescents increasingly use the Internet for communication, education, entertainment, and other purposes in varying degrees. Given their vulnerable age, they may be prone to Internet addiction.
Our aim was to identify possible differences in the purpose of Internet use among adolescents with respect to age subgroup, country of residence, and gender and the distribution of Internet addiction across age subgroups. Another aim was to determine if there is a correlation between the purpose of Internet use and age and if this interaction influences the level of addiction to the Internet.
The study included a simple random sample of 1078 adolescents—534 boys and 525 girls—aged 11-18 years attending elementary and grammar schools in Croatia, Finland, and Poland. Adolescents were asked to complete an anonymous questionnaire and provide data on age, gender, country of residence, and purpose of Internet use (ie, school/work or entertainment). Collected data were analyzed with the chi-square test for correlations.
Adolescents mostly used the Internet for entertainment (905/1078, 84.00%). More female than male adolescents used it for school/work (105/525, 20.0% vs 64/534, 12.0%, respectively). Internet for the purpose of school/work was mostly used by Polish adolescents (71/296, 24.0%), followed by Croatian (78/486, 16.0%) and Finnish (24/296, 8.0%) adolescents. The level of Internet addiction was the highest among the 15-16-year-old age subgroup and was lowest in the 11-12-year-old age subgroup. There was a weak but positive correlation between Internet addiction and age subgroup (
Adolescents aged 15-16 years, especially male adolescents, are the most prone to the development of Internet addiction, whereas adolescents aged 11-12 years show the lowest level of Internet addiction.
Adolescence can be defined as the period between puberty and adulthood, usually between the ages of 11 and 18 years. Events during this period greatly influence a person's development and can determine their attitudes and behavior in later life [
Study participants were 11- to 18-year-old students who attended regular public schools. They comprised a simple random representative sample of adolescents. Using a table of random samples, we selected the city of Split in Croatia, the town of Pakość in Poland, and the city of Turku in Finland. To select schools, we used the method of random numbers, always respecting the structure of education. In Split, four schools per 100 students were randomly selected, while two schools per 100 students were randomly selected in each of Pakość and Turku (see
Elementary and high schools in Croatia, Poland, and Finland randomly selected for the study.
School location | School name and address |
Poljišani Elementary School, Viška 12 | |
Blatine-Škrape Elementary School, Kržice 2 | |
Third Gymnasium |
|
First Gymnasium School, Teslina 10 | |
Szkoła Podstawową im. Powstańców Wielkopolskich w Pakości, Błonie 2 | |
Gimnazjum im.Ewarysta Estkowskiego w Pakości, ul.Szkolna 44 | |
Raunistulan koulu, Teräsrautelan koulu /Suikkilan yksikkö, Talinkorventie 16 | |
Turun suomalaisen yhteiskoulun lukio, Kauppiaskatu 17 |
The study was approved by respective ministries of education in Croatia, Poland, and Finland and ethics committees of the schools. The schools were sent an invitation to participate in the study, with the assurance of complete student privacy protection. Informed consent was obtained from each student and their parents or guardians.
The questionnaire was developed in Google Docs format and sent to schools in an electronic form along with instructions and contact information of the researchers. The title page instructed the students to fill out the questionnaire fully and truthfully. They were informed that their participation was anonymous and voluntary and that the data would be used for research purposes only. General and particular importance of the research was also explained. Furthermore, the students were notified of the type and duration of the procedures used and informed of the confidentiality of the data gathered and the protection of privacy of the participants. The students were free to refuse participation or to withdraw from the study at any time without explanation. Having been notified of all the particulars, they proceeded to fill out the questionnaire.
Our research systematically analyzed all significant variables necessary for scientific research. The survey consisted of three parts. A standardized procedure of double translation was applied to each part for each country and its language. The initial step was defined by taking the general data and demographic measures. Demographic parameters used in the research included age, gender (1=female, 2=male), country of residence, and purpose of Internet use (eg, school/work or entertainment). Participants were asked to appraise whether they use the Internet more often for entertainment or educational purposes.
Specific aspects that have been included in a more detailed analysis of research on Internet addiction have been assessed in previous studies. These include assessing Internet addiction using Young’s Internet Addiction Test (IAT) [
For statistical analysis, SPSS Statistics for Windows version 17.0 (SPSS Inc) was used. For data analysis, three groups of methods were used: descriptive statistical analysis (ie, relative numbers, median, and measures of dispersion), inferential statistical analysis (ie, chi-square test,
Distribution of adolescents (pooled data) with respect to gender, age, country of residence, and purpose of Internet use (in percentages).
A total of 1078 adolescents from Croatia, Poland, and Finland participated in the research (see
The representative sample included 534 boys and 525 girls; gender was unknown for 19 participants. The average age of participants was 14.9 years (SD 1.9, range 11-18), with an average discrepancy of 1.9 years, which is a small dispersion (variance coefficient 13%). Since participants were predominantly 15-year-olds, both the median and mode values were 15 years. There were more participants from Croatia than from either of the other two countries. A large majority of participants used the Internet for entertainment purposes (905/1078, 84.00%), whereas only a small proportion used it for school/work (172/1078, 16.00%).
We found a statistically significant relationship between the purpose of Internet use and gender (χ21=11.3; n=1042;
Female participants used the Internet for school- or work-related purposes (105/525, 20.0%) much more than their male counterparts (64/534, 12.0%). However, when the analyses of this correlation between gender and the purpose of Internet use were carried out separately for each country, the results became more revealing (see
A statistically significant relationship was found for Croatian participants (χ21=26.8; n=476;
We found a statistically significant correlation between the country of residence and the purpose of Internet use (χ22= 27.3; n=1048;
Number of interviewed adolescent participants according to gender and purpose of Internet use (n=1042).
Purpose of Internet use, n | ||||
Entertainment | School/work | Total | ||
Male | 459 | 65 | 524 | |
Female | 414 | 104 | 518 | |
Total | 873 | 169 | 1042 |
Correlation between gender and purpose of Internet use for each country.
Country | χ2 | df | n | |
Croatia | 26.8 | 1 | 476 | <.001 |
Poland | 0.2 | 1 | 291 | .65 |
Finland | 0.2 | 1 | 275 | .63 |
Number of interviewed adolescent participants according to their country of residence and purpose of Internet use (n=1048).
Purpose of Internet use, n | ||||
Entertainment | School/work | Total | ||
Croatia | 400 | 78 | 478 | |
Poland | 225 | 70 | 295 | |
Finland | 254 | 21 | 275 | |
Total | 879 | 169 | 1048 |
There was a statistically significant correlation between age and the level of Internet addiction (χ26=19.7; n=919;
Contingency table (4 × 2 format) showing correlation between age of adolescent participants and Internet addiction.
Variables | Analyzed group | n | χ2 | df | |
Age of adolescents (4 groups) |
Male participants | 469 | 16.9 | 3 | .001 |
Age of adolescents (4 groups) |
Female participants | 447 | 0.5 | 3 | .93 |
Age of adolescents (4 groups) |
Participants from Croatia | 397 | 5.8 | 3 | .12 |
Age of adolescents (4 groups) |
Participants from Poland | 270 | 3.8 | 3 | .29 |
Age of adolescents (4 groups) |
Participants from Finland | 252 | 1.1 | 3 | .81 |
Age of adolescents (4 groups) |
Participants who used the Internet for school/work | 145 | 7.4 | 3 | .06 |
Age of adolescents (4 groups) |
Participants who used the Internet for entertainment | 760 | 8.4 | 3 | .04 |
In a correlation analysis, age was considered as a continuous independent variable and Internet addiction as a dependent ordinal variable. A nonparametric method was used to calculate the Spearman coefficient of correlation of .08 for n=1033 and with
In describing the analysis data obtained through the described model, the Levene test of variance equality has to be mentioned first, as it has established that variances were not homogenous (
The obtained results (see
Comparing the eight mean values among themselves, we are able to determine the lowest and the highest level of Internet addiction. The lowest level of Internet addiction was found among the youngest age group who used the Internet for school, whereas adolescents between the ages of 15 and 16 years who used the Internet for school had the highest level of Internet addiction (see
A single-factor variance analysis (
The average overall score was 37.8 (SD 12.3). There was a statistically significant difference between the four averages (
Adolescents aged 15-16 years who also used the Internet for school had the highest level of Internet addiction (see
The analysis data obtained through the described model.
Source variation | The sum of squares | df | The middle square | ||
Factor 1: the purpose of Internet use | 220.152 | 1 | 220.152 | 1.54 | .22 |
Factor 2: age | 6686.400 | 3 | 2228.800 | 15.61 | <.001 |
Interaction: the purpose of Internet use x age | 2286.327 | 3 | 762.109 | 5.33 | .001 |
Summary results of descriptive statistical analysis with analysis of variance.
Age group (years) | Purpose of Internet use | Mean (SD) |
School/work | 32.5 (9.5) | |
Entertainment | 32.8 (9.4) | |
School/work | 34.8 (9.1) | |
Entertainment | 38.2 (10.9) | |
School/work | 46.5 (20.2) | |
Entertainment | 39.3 (11.9) | |
School/work | 38.2 (11.1) | |
Entertainment | 35.9 (11.9) |
Results of the
Age group (years) | n | Internet addiction, mean (SD) | ||
11-12 | 115 | 32.4 (9.5) | ||
13-14 | 267 | 37.6 (10.7) | ||
15-16 | 323 | 40.4 (13.9) | ||
17-18 | 205 | 36.4 (12.0) | 14.46 | .001a |
aStatistical significance at 0.1%.
Results of the Bonferroni post hoc test (
Age group (years) | Age group (years), |
||
13-14 | 15-16 | 17-18 | |
11-12 | .001a | <.001a | .03b |
13-14 | .004b | >.99 | |
15-16 | .001a |
aStatistical significance at 0.1%.
bStatistical significance at 5%.
Comparison of the average values (points) of Internet addiction in adolescent participants of different age.
The objective of our study was to investigate if there were differences among adolescents in Croatia, Poland, and Finland regarding the purpose of their Internet use with respect to their age subgroup and gender. Our findings showed that a majority of adolescents used the Internet for entertainment and only one-sixth of them used it for school/work. Female adolescents used the Internet for school/work significantly more than did their male counterparts. The use of the Internet for school was most frequent among Polish adolescents, followed by Croatian adolescents, and least common among Finnish adolescents. Lenhart and Madden found similar results in their study, reporting that male adolescents in America use the Internet for functional and entertainment activities much more than female adolescents who use it for educational and social activities to a much higher degree [
Our study did not manage to clarify the relationship between the different developmental phases of adolescence and the growing number of Internet addicts. Another limitation of this study is that we have no specific clinical criteria to determine which children aged 15-16 years are the most sensitive and most vulnerable to Internet addiction. Thus, the current findings increase our understanding of the relationships between Internet addiction and different developmental phases of adolescence.
The primary purpose of Internet use among the 1078 participants was entertainment (905/1078, 84.00%) while the secondary purpose was school/work (172/1078, 16.00%). A total of 20.0% (105/525) of female adolescents used the Internet for school/work, which was significantly more than the males (64/534, 12.0%). Croatian participants (78/486, 16.0%) used the Internet for school/work significantly less than did the Polish participants (71/296, 24.0%); the Finnish participants used it for school/work the least (24/296, 8.0%). The percentage of moderate and serious Internet addicts increased with age. Most adolescent Internet addicts were in the middle stage of adolescence (ie, the 15-16-year-old age group). Furthermore, the purpose of Internet use had no effect on the level of Internet addiction. Age was a significant predictor of the level of Internet addiction as was the interaction between the purpose of Internet use and age. After comparing the eight mean values between themselves, we learned that the level of Internet addiction was the lowest among the youngest group (11-12 years) that used the Internet for school. They also had the lowest rate of Internet use for entertainment. The highest level of Internet addiction was found among the group of 15-16-year-olds. This group had the highest rate of Internet use for school, but also for entertainment. In the 13-14-year-old age group, 38.2% (116/303) of adolescents used the Internet for school and 34.2% (104/303) for entertainment. In the 17-18-year-old age group, 38.2% (91/237) of adolescents used the Internet for school/work and 35.9% (85/237) used it for entertainment.
Diagnostic and Statistical Manual of Mental Disorders
Internet Addiction Test
The authors would like to acknowledge the schools that participated in this research: Poljišani Elementary School (Split, Croatia), Blatine-Skrape Elementary School (Split, Croatia), First Gymnasium School (Split, Croatia), Third Gymnasium School (Split, Croatia), Raunistulan koulu, Teräsrautelan koulu/Suikkilan yksikkö (Turku, Finland), Turun suomalaisen yhteiskoulun lukio (Turku, Finland), Szkoła Podstawowa im. Powstancow Wielkopolskich w Pakość i (Pakość, Poland), and Gimnazjum im. Ewerysta Estkowskiego w Pakość i (Pakość, Poland).
None declared.