This study was carried out at an inpatient clinic in Norway. A six- week long treatment programme included intensive group therapy, but also five hours of individual therapy, given as motivational interviewing (MI). Thirty-one patients were randomized either to receive five individual sessions of hypnotherapy instead of MI (N=16) or to be in the control group (N=15). The treatment method for the hypnotherapy group was Erickson's (permissive) hypnosis. At baseline all the participants were diagnosed using a psychiatric interview and filled in the Alcohol Use Identification Test (AUDIT), Time-line-follow-back (TLFB) for alcohol use, Hopkins Symptoms Check List (HSCL-25) for monitoring mental distress and Traumatic Life Events Questionnaire. AUDIT, TLFB and HSCL-25 were re-administered at follow-up after one year.

This study was designed as a parallel study, where two groups were compared: one receiving treatment as usual (motivational interviewing) and the intervention (hypnotherapy group). With difference in treatment effect as great as 40% we would have needed 46 participants to achieve p=0.05. We had initially planned to recruit as many as 50 individuals, but many were sceptical to the novel treatment. Four persons withdrew from the hypnotherapy group either before or after first treatment because of uncertainty. This did not affect randomization and they are not represented in the results.

Participants in the study were recruited from patients admitted to a six week long inpatient treatment programme at Vangseter Clinic in Norway in 2016. Only individuals who suffered from AUD were included in this study. The treatment programme consisted of the following elements: 5 hours of group therapy 5 days a week, a 2-3 day long family visit, where a family therapy session was also included, some obligatory group activities, like trips to museums or walks in nature, and lastly, informal activities, such as barbecues, watching movies together or discussions in the hall. All this was thought to contribute to the therapy of the patients. From the second week of the program the patients were expected to have one hour of additional individual therapy a week. It was conducted as motivational interviewing (MI), totaling five hours. MI is one of the most popular and effective modern treatments. As a brief intervention, MI appears to be at least as effective as, and possibly more effective than, other treatment methods. As an alternative to the MI sessions the patients enrolled in the study could receive five individual hour-long sessions of hypnotherapy.

Patients were informed about the study, were given time to consider, and if they volunteered to participate then signed a consent form. Thirty-one individuals, who took part in this randomized controlled trial (RCT), were assigned at random to receive either hypnotherapy (N=16) or to be in the control group (N=15).

At the beginning of the second week of treatment (baseline) all the participants were administered Mini International Neuro-psychiatric Interview (MINI) psychiatric interview to be able to diagnose mental problems other than AUD. Exclusion criteria were having psychotic episodes, a recent severe other psychiatric diagnosis or recent drug abuse other than alcohol.

In addition, all patients filled in the Alcohol Use Identification Test (AUDIT) and a Time-line-follow-back (TLFB) for registration of number of standardized alcohol units consumed and alcohol-related problems during the previous month. They also filled in the Hopkins Symptoms Check List (HSCL-25) to measure their level of mental distress. Mental distress was given as a global average of the HSCL-25 denoted Global Severity Index (GSI). The Traumatic Life Events Questionnaire was used to register traumatic life experiences. AUDIT, TLFB and HSCL-25 were re-administered one year later as a follow-up.

The intervention consisted of hypnotherapy given as five one-hour sessions over 5 weeks as individual therapy instead of motivational interviewing. The treatment method was Erickson's (permissive) hypnosis. Each treatment session began with a conversation about the patient's past life events, present situation, alcohol problem and his or her thoughts about it. To be able to use visualisation, patients were always asked when and where they bought alcohol, and how it was consumed. During the first part of the treatment session the theme of the hypnotic intervention was formulated, and then hypnotic trance was induced. The induction method was mostly a combination of relaxation and breathing exercises with mental pictures of a peaceful place. Once the trance was induced, the patient was asked to visualize mastery of a selected situation. This situation was tailored according to the patient's needs. It could include, for example, abstaining from alcohol at a party, passing an alcohol shop without going inside, or mastering another problematic issue, such as staying relaxed and calm in the presence of other people. When indicated, the events of the past were a subject of hypnotic intervention as well.

Data were analysed using Statistical Package for the Social Sciences (SPSS; IBM statistics) version 25, using simple bivariate analysis (Student's T-test or chi-square test), comparing the intervention group and the control group. Level of significance was set to p < 0.05, but even higher values were considered as the risk of type II statistical errors would be substantial in the small randomized controlled trial.

Inclusion Criteria:

• Only individuals who suffered from AUD were included in this study.

Exclusion Criteria:

• Exclusion criteria were having psychotic episodes, a recent severe other psychiatric diagnosis or recent drug abuse other than alcohol.