Insomnia in the Patient With Schizophrenic Disorder: Evaluation of a CBT and Psychoeducational Intervention

Insomnia severity was assessed using the Insomnia Severity Index (ISI) (Morin, 1993), a self-applied instrument designed to briefly assess the severity of insomnia in the general population based on the diagnostic criteria of the DSM-IV and the ICSD. A 5-point Likert scale is used to rate each item (0 = no problem; 4 = very severe problem), yielding a total score ranging from 0 to 28. The total score is interpreted as follows: not clinically significant insomnia (0-7); subthreshold insomnia (8-14); moderate insomnia (15-21); and severe insomnia (22-28) This scale has been found to have adequate psychometric properties in studies conducted using English version (Bastien et al, 2001), with internal reliability values (Cronbach's a) between 0.74 and 0.90, and test-retest reliability equal to 0.89 one month after evaluation, 0.77 two months after, and 0.73 three months after. Two validation studies of the Spanish version of the ISI (Fernandez-Mendoza et al., 2012; Sierra et al, 2008)

The quality of sleep has been analysed by The Pittsburgh Sleep Quality Index, which is made up of 19 self-administered questions. The 19 self-rated questions assess a wide variety of factors relating to sleep quality, including estimates of sleep duration and latency and of the frequency and severity of specific sleep-related problems. These I9 items are grouped into seven component scores, each weighted equally on a O-3 scale. The seven component scores are then summed to yield a global PSQI score, which has a range of 0-21; higher scores indicate worse sleep quality (Buysse et al. 1989) . This tool has shown in its English version acceptable measures of internal homogeneity, consistency, and validity were obtained. A global PSQI score greater than 5 yielded a diagnostic sensitivity of 89.6% and specificity of 86.5% in distinguishing good and poor sleepers (Buysse et al. 1989) Tool that has been adapted in its Spanish version (Macias Fernandez and Royuela Rico 1996)

Health-related quality of life (HRQoL) has been assessed using the EuroQol-5D Scale (EQ-5D) (EuroQol Group 1990) a self-applied scale that is quick and easy to administer, yielding a multidimensional description of general health as well as a numerical health profile. The scale is made up of two parts, the EQ-5D descriptive system, 5 dimensions (mobility, self- care, usual activities, pain/discomfort, and anxiety/de- pression), each with 3 levels of severity (value 1 = no problems, value 2 = some problems, value 3 = severe problems) and the visual analogue scale (EQ-VAS) (value 0 = worst and value 100 = best imaginable health status). This scale has been validated in Spain by Xavier Badia (Badia et al. 1999). For psychometric properties, the scale presented a test-retest reliability between 0.86 and 0.90 (van Agt et al. 1994) and a strong correlation with the SF-36 scale. The EQ-5D scale has also been shown to be valid for use with patients with schizophrenia (Prieto et al. 2004)