Study on the Psychotherapeutic Treatment of Chronic Nightmares

Nightmare Frequency Questionnaire (NFQ, Krakow et al., 2000) number of nightmares per week. The participant is asked to state the number of nightmares in the last three months, the response is to be given as an absolute frequency per year, month, or week, whichever is applicable. The range is zero to any number the participant states, the maximum number reported was 20.

Nightmare Effects Survey (NES, Krakow et al., 2000) The first item asks whether the person's life is generally affected by nightmares. The remaining eleven items list areas in daily life (sleep, work, relationships, daytime energy, school, mood, sex life, diet, mental health, physical health, and leisure activities) rated on 5-point Likert scales regarding how much they are "adversely or negatively affected by nightmares". The range is 0 to 44, and higher values indicate more effects.

Nightmare Distress Questionnaire (NDQ, Belicki, 1992) The NDQ consists of 13 items rated on 5-point Likert scales. Eleven items pertain to daytime consequences of nightmares (e.g., disliking someone because they were in a nightmare; being afraid to fall asleep for fear of having a nightmare); two items explore interest in professional help and treatment. The range is 13 to 65, and higher values indicate more distress.

self rated: Beck Anxiety Inventory: 21 Items to be rated on 0 to 3 scales, range 0 to 63, higher values indicate higher anxiety in both measures rated by therapist on Hamilton Anxiety Scale: 14 Items to be rated on 5-point-scales from "not at all" to "very strong", range 0 to 56

self rated: Beck Depression Inventory II, 21 Items to be rated on 0 to 3 scales, range 0 to 63 rated by therapist on Hamilton Depression Scale, 21 Items to be rated on 0-2 or 0-4 scales, range 0-66, higher values indicate higher depression in both measures

Landeck Inventory for the Assessment of Sleep Disorders (LISST, Weeß, 2002): This is a screening instrument for sleep disorders, only the item measuring dream recall and the 8-item sleep quality subscale were used. Both use 6-point Likert scales. The sleep quality subscale score range is 0 to 40, and higher values indicate lower sleep quality.

Selbstwirksamkeitsskala (General self efficacy, Jerusalem & Schwarzer, 1998) This 10-item measure contains statements such as "I am confident that I could deal efficiently with unexpected events" or "I can usually handle whatever comes my way" rated on 4-point Likert scales. The scale was used to operationalize mastery. Its range is 10 to 40, with higher values indicating higher self-efficacy.

Symptom Checklist 90-R The SCL measures a wide variety of psychopathological symptoms. The Global Severity Index (GSI) was used. Its range is 0 to 4, with higher values indicating more and/or more intense symptoms.