Some causes listed include deaths also included in more specific subordinate causes (as indicated by the "Group" column), and some causes are omitted, so the percentages may only sum approximately to 100%. The causes listed are relatively immediate medical causes, but the ultimate cause of death might be described differently. For example, tobacco smoking often causes lung disease or cancer, and alcohol use disorder can cause liver failure or a motor vehicle accident. For statistics on preventable ultimate causes, see preventable causes of death.