The purpose of this study was to generate a suitable tool to estimate the prevalence, characteristics and cultural connotations  of sleep paralysis in Taiwan. Although the idea of Gui ya chuang (鬼壓床-sleep paralysis) is very common in Taiwan, the concept of sleep paralysis as a distinct sleep disorder is rather uncommon for the average Taiwanese person. At present there was no suitable scale or questionnaire to evaluate sleep paralysis in Taiwan. The study translated and validated The Waterloo Unusual Sleep Experiences Questionnaire (WUSEQ) in order to develop a questionnaire suitable for the Taiwanese population. The sample of the research was comprised of 311 Taiwanese people whose age was within 20-80. The result of principal axis factoring of Chinese version of WUSEQ (C-WUSEQ) indicated that the constructs of C-WUSEQ has good to acceptable internal consistency. We found three constructs which fit to the theory of hallucination experience items - intruder, incubus, and vestibular-motor hallucinations. The items of each constructs could separately explain 15.45%, 11.47%, and 10.67% of each categories. In summary, the present study shows C-WUSEQ is a suitable tool to deep down recognizing sleep paralysis and associated issues.

Introduction 1
Literature review 3
Pathology 3
Prevalence 4
Pharmacological and Psychological approaches to treatment 6
Cultural connotations 7
The Waterloo Unusual Sleep Experiences Questionnaire (WUSEQ) 8
Methods 11
Translation 11
Discussion-Group 11
Validation 11
Participants 12
Instruments 13
Statistical analysis 13
Results 15
Participants 15
Reliability and Validity 17
Sleep paralysis Frequency and Intensity of hallucinations 19
Sleep position in sleep paralysis or normal sleep 27
Occurrence time of sleep paralysis 28
Factors which the participants consider as plausible causes of sleep paralysis 30
The diagnosis of the participants 31
Discussion 33
Study limitations 35
Future directions 35
References 37
Appendix A 41
Appendix B 55

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