METHODS AND FINDINGS: We used data on suicides by gases other than domestic gas for Hong Kong, Japan, the Republic of Korea, Taiwan, and Singapore in the years 1995/1996-2011. Similar data for Malaysia, the Philippines, and Thailand were also extracted but were incomplete. Graphical and joinpoint regression analyses were used to examine time trends in suicide, and negative binomial regression analysis to study sex- and age-specific patterns. In 1995/1996, charcoal-burning suicides accounted for <1% of all suicides in all study countries, except in Japan (5%), but they increased to account for 13%, 24%, 10%, 7%, and 5% of all suicides in Hong Kong, Taiwan, Japan, the Republic of Korea, and Singapore, respectively, in 2011. Rises were first seen in Hong Kong after 1998 (95% CI 1997-1999), followed by Singapore in 1999 (95% CI 1998-2001), Taiwan in 2000 (95% CI 1999-2001), Japan in 2002 (95% CI 1999-2003), and the Republic of Korea in 2007 (95% CI 2006-2008). No marked increases were seen in Malaysia, the Philippines, or Thailand. There was some evidence that charcoal-burning suicides were associated with an increase in overall suicide rates in Hong Kong, Taiwan, and Japan (for females), but not in Japan (for males), the Republic of Korea, and Singapore. Rates of change in charcoal-burning suicide rate did not differ by sex/age group in Taiwan and Hong Kong but appeared to be greatest in people aged 15-24 y in Japan and people aged 25-64 y in the Republic of Korea. The lack of specific codes for charcoal-burning suicide in the International Classification of Diseases and variations in coding practice in different countries are potential limitations of this study.
CONCLUSIONS: Charcoal-burning suicides increased markedly in some East/Southeast Asian countries (Hong Kong, Taiwan, Japan, the Republic of Korea, and Singapore) in the first decade of the 21st century, but such rises were not experienced by all countries in the region. In countries with a rise in charcoal-burning suicide rates, the timing, scale, and sex/age pattern of increases varied by country. Factors underlying these variations require further investigation, but may include differences in culture or in media portrayals of the method. Please see later in the article for the Editors' Summary.
Objective: The aim of this study was to develop and assess an equivalent modified FTND scale that measures the nicotine dependency via EC.
Materials and Methods: The investigator developed the equivalent modified FTND scale that scores identical to the original scale, that is, 0-10. The developed scale piloted among 15 EC single users, that is, use only EC verified by carbon monoxide (CO) level of <8ppm. The assessment of the scale was done among 69 EC single users and observed for 1 year to determine their nicotine status.
Results: The modified scale revealed an acceptable Cronbach α value of 0.725. Further test-retest reliability of the scale showed a satisfactory Spearman's rank correlation coefficient value of 0.730 (P > 0.05). A 1-year observation showed that of 69 single users, 11 single users completely stopped nicotine intake, 24 remained as EC single users, 15 shifted to dual-use, and 19 relapsed to TCG. Surprisingly, the EC users who completely stopped nicotine intake after 1 year had a low average nicotine dependence value of 3 that was measured by the modified FTND scale at the baseline.
Conclusion: The modified FTND scale precisely identifies the physical dependence to nicotine via EC. Therefore, as per this study results the modified FTND scale can be applied in any EC-related studies to assess nicotine dependency via EC.