“Gender” and “Age” of the respondents were obtained from the Basic Resident Register. Age was then divided into the three categories: “Under 20,” “20 to 64,” and “65 and over.” “Community size” of the respondents was obtained from the population statistics disclosed by municipalities listed in the Basic Resident Register and was divided into the four categories: “City designated by government ordinance or Tokyo’s 23 wards,” “City (population of 150,000 and more),” “City (population less than 150,000),” and “Town or village.”

As indicators of the socio economic status of the respondents, data on their “Annual household income” and “Amount of savings” was collected. Respondents who knew their annual household income or amount of savings used a 14-point scale ranging from “Less than 1 million yen” to “13 million yen or more” to answer. If they did not know their annual household income or amount of savings, they were asked to choose “Don’t know.” In the tabulation process, “Annual household income” was divided into five categories: “Don’t know” and four categories ranging from “Less than 3 million yen” to “8 million yen or more.” Similarly, “Amount of savings” was divided into the three categories: “Don’t know,” “Have no savings,” and “Have savings.” As an indicator of educational level, the respondents were asked about their highest educational attainment.

The respondents were asked whether or not they had divorce experience.

Regarding nine types of official gambling games, such as horse racing and the lottery, the respondents were asked how frequently they had played them in the past 12 months. Again, a 4-point scale was used. In the tabulation process, respondents who experienced at least one of the nine gambling games were categorized as “Have experience” and those who had no experience with any of the gambling games were categorized as “No experience.”

The PPDS was developed based on items in gambling disorder scales such as the SOGS, DSM-IV, NODS, PGSI, and G-SAS [9] [10] [11] [12] [13]. It consists of 27 items in 12 categories to measure the three factors of the disorder: motivation, behavior, and consequence (See Table 1). It is designed to ask individuals

who played pachinko/pachislot in the last 12 months about their behavior and experience associated with gambling disorder in that period. Among 27 items, 26 were in the form of a 4-point scale ranging from “Disagree” to “Agree” or from “Never” to “Often.” The remaining item was about borrowing money and was presented in the form of a multiple answer question. The respondents were asked to select all places from which they borrowed money. Responses on the 4-point scales were converted into 1 to 4 points, with “Disagree” and “Never” being 1 point. Responses on the multiple answer question on borrowing money were converted into 0 to 7 points. The score was 0 if the respondents selected “Never borrowed,” but otherwise the number of places from which the respondents borrowed money became the points for that question. The sum of the 4-point scale points and the points for the question on borrowing money were used in the analysis as the Pachinko-pachislot Playing Disorder Scale score (PPDS score). The obtained PPDS score ranged from 26 to 111.

No significant gender difference was found between the Disorder and Non-Disorder Groups. In both groups, male pachinko/pachislot players accounted for more than the female counterparts (χ²(1) = 2.61, n.s., V = .07). No significant age differences were found between the two groups either. There were no particular age groups having high percentages of individuals with gambling disorder (χ²(2) = 0.68, n.s., V = .03). There was also no significant difference in distribution of areas of living (χ²(3) = 3.93, n.s., V = .08). Although some studies reported that the prevalence of gambling disorder was higher for men or younger age groups [14] , there were also study results showing the possibility of gender and age influencing the prevalence at different levels depending on how they interact with other variables. In the case of electronic gambling machines (EGMs), which are similar to pachinko/pachislot machines, no sexual difference was found in the prevalence when the frequency of play was controlled [15]. In a previous gambling disorder study in Japan, Nishimura and Ishida [16] used data from individuals who called a telephone consulting agency to talk about their pachinko addiction to show that men scored significantly higher on the short form of the SOGS for addicted gamblers. When the same callers were divided into problem gamblers and non-problem gamblers using the cut-off value, however, there was no significant sexual difference. In pachinko/pachislot, gender strongly influences the rate of participation, but its influence on the level of disorder seems marginal.

Individuals with gambling disorder and those without showed no differences in the distributions of the two socio-economic status indicators, “Highest educational attainment” and “Annual household income”. (Highest education attainment: χ²(5) = 3.08, n.s., V = .08; Annual household income U = 2380.50, n.s., r = −.07). On the other hand, a significant difference was found in the distribution of “Amount of savings.” The Disorder Group had a higher percentage of individuals who reported they had no savings (χ²(2) = 23.98, p < .001, V = .21). SES, like gender, is considered to be a risk factor for gambling disorder. However, the influence of SES could change with other variables as reported in a previous study where its relationship with gambling disorder became apparent only after other risk factors such as race and marital history were controlled [17].