The Swedish psychologist and university professor Heinz Leymann developed the LIPT questionnaire. LIPT stands for Leymann Inventory of Psychological Terror.
The LIPT questionnaire lists 45 mobbing actions at the workplace. A person is regarded as being bullied if one or more of the 45 actions happen at least once per week over a period of at least one year. Alternative mobbing definitions require a shorter period of at least 3–6 months and the frequent occurrence of more than one action.
The effects of the actions on the mobbing victim are divided into five categories:
The 45 mobbing actions are derived by Leymann from 300 individual interviews in the years of 1981 to 1984. After 1984 the interviews did not find further actions and ended.