The recent development of Internet-based smart instruments has brought about a groundbreaking change in the society. In South Korea, according to the report of Korea Communications Commission, the smartphone users have been estimated to be over 20 million, and according to Statistics Korea, roughly over half of 40 million people (15-year-olds) carry smartphones, which means that smart instruments have spread considerably [1].
It is surprising that a tiny smartphone is built on a mobile computing platform with a more advanced computing ability and connectivity. Modern smartphone models serve to combine the functions of portable media players, low-end compact digital cameras, pocket video cameras, and GPS navigation units. Lately, smartphones typically have the functions of high-resolution touch screens, Web browsers that can access and properly display standard Webpages, and high-speed data access via Wi-Fi and mobile broadband. These advantages have brought enormous convenience to the modern society, but considering that smartphones are sharing most aspects of the Internet, the addiction to smartphones is highly likely to cause physical and psychosocial problems as well as Internet addiction [2]–[4].
Adverse results caused by the overuse of smartphones can be easily seen in today's society. For example, pedestrians viewing smartphone videos when crossing the street, without checking the traffic signal, are in danger of getting hit by cars; fumbling with one's smartphone while driving may cause car accidents; and elementary-school-aged children are highly likely to be addicted to smartphone games as well as to Internet video games [5]. In addition, students cannot concentrate in class, and the average cost of mobile-phone usage is increasing [1].
In a survey conducted by Stanford University in 2010, it was found that in 200 iPhone-using students, the Apple smartphone (a typical smartphone brand) can be rather addictive for both its recent adoptees and its long-time users, and many users relied on iPhone as a part of their lifestyle. All in all, 10% of the participants were fully addicted to their iPhone, 34% ranked themselves almost addicted to it, and 6% said they were not addicted to it at all. Further, 75% admitted to sleeping next to their iPhone, and 69% reported that they were more likely to forget their wallet than their iPhone. Although the admission of severe addiction was not very high among the side effects of iPhone addiction, with 41% saying it would be “a tragedy” to lose their iPhone and 22% saying that it is “dangerously alluring,” the rates still indicated the addictive power of smartphones [6].
Moreover, media reports suggest that people are becoming more attached to their smartphones, with ensuing social difficulties. A Website called “Crackberry.com” includes an online forum for “abusers” to admit their “addiction,” and a notice board for Blackberry “users and abusers,” where thousands of users discuss their addicted smartphone use. These self-report evidences indicate that a large number of users may be experiencing unwanted reliance on their smartphones [7].
“Addiction” is defined in the dictionary as: (1) a functional abnormality of the body caused by food or pharmaceutical toxins; (2) a pathologic condition that one cannot tolerate without the continuous administration of alcohol or drugs; and (3) the status of not being able to rationally judge or distinguish due to certain ideas or objects. “Addiction,” however, commonly handled by neuropsychiatric departments, is a phenomenon that manifests tolerance, withdrawal symptoms, and dependence, accompanied by social problems [8], [9]. The term was once limited to drugs or substances, but it is now also applied to gambling, Internet, gaming, mobile-phone usage, and other behavioral addictions [10].
The project “Development of a Korean Smartphone Addiction Proneness Scale” carried out by National Information Society Agency aimed to shed light on the concept and perception of smartphone addiction. In the project, each subject group was assessed, and the subjects were divided into the high-risk group, the low- to medium-risk group, and the general group. According to the results report, the smartphone addiction rates of the high-risk group and of the low- to medium-risk group were 2.2 and 9.3%, respectively, in adolescents, and 1.0 and 6.7%, respectively, in adults [11]. This indicates that the smartphone-related problems are too critical to be neglected. The project, however, provided only a simple assessment, differentiating between dependence and abuse, based on psychiatric diagnosis. As such, there is an urgent need to develop a diagnostic scale for smartphone addiction.
As it has been hypothesized that smartphone addiction has many aspects that are similar to those of Internet addiction, and as such, the Internet addiction criteria must be considered when developing smartphone addiction criteria. As Internet addiction has brought about a series of negative results due to the rapid development of the IT industry and of its increasing usage rate, it has become a popular issue, and many researches have been conducted on it. Kimberly S. Young was the first researcher to have established a basis for Internet addiction criteria, which has been widely quoted since then. In South Korea, a Korean self-diagnostic program for Internet addiction (K-scale) resulted from a joint research effort by Korea Agency for Digital Opportunities and Seoul National University [12]–[15]. K-scale was developed from Kimberly Young's scale of 20 questions into a 40-item scale.
Despite the importance of the smartphone-related problems, at the time of this study, there had been no studies focusing on this issue. Hence, the purpose of this study was to develop a self-diagnostic scale that could distinguish smartphone addicts. Based on K-scale and the smartphone's characteristics, the first smartphone addiction scale (SAS) was developed. Then, after revising the scale via factor analysis, the final SAS was completed.