BJPsych：偏执在自然人群中的类别构成

　　精神病症候似乎形成了一个正常体验个信仰的连续体，并可能建立在普通人际化情感交往上。《英国精神病学杂志》（The British Journal of Psychiatry）6月在线刊登的一项研究的结果显示，偏执连续体蕴含精神障碍的病因学、机理及治疗的线索，同时证实了其与正常体验及情感进程间缺乏明确的区分标准。

　　研究者假设偏执在自然人群中呈指数分布和分级排列，且迫害妄想是建立在不信任、人际敏感和牵连观念等普通认知上的，并且对以上假设进行了验证。

　　研究调查项目选自美国《精神疾患诊断与统计手册》（DSM-IV）轴II障碍（SCID-II）临床定式检查调查问卷，及全英第二次精神疾病发病率调查（n=8580）使用的精神病筛查问卷。采用验证性因素分析、潜类别分析及因素混合建模分析对偏执发展过程中的一个假定层级进行检测。

　　结果发现，以发生率来界定不同种类的偏执，发生率范围从小于2%到接近30%。研究项目的总体评分依从一个几乎完美的指数分布（r=0.99）。四个先验一阶因素得到了证实（人际敏感、不信任、牵连观念及被害妄想）。这些映射为独立受访者的四个类别：1、一种罕见的严重的被害妄想状态，受访者确认存在包括偏执在内的所有项目因素；2、一种拟正常状态，受访者确认存在不常见的人际敏感、不信任和牵连观念，但无被害妄想；3、两种中性状态，以与不信任或牵连观念等项目的相对高认可度为特点。

The structure of paranoia in the general population
Background
Psychotic phenomena appear to form a continuum with normal experience and beliefs, and may build on common emotional interpersonal concerns.
Aims
We tested predictions that paranoid ideation is exponentially distributed and hierarchically arranged in the general population, and that persecutory ideas build on more common cognitions of mistrust, interpersonal sensitivity and ideas of reference.
Method
Items were chosen from the Structured Clinical Interview for DSM-IV Axis II Disorders (SCID-II) questionnaire and the Psychosis Screening Questionnaire in the second British National Survey of Psychiatric Morbidity (n = 8580), to test a putative hierarchy of paranoid development using confirmatory factor analysis, latent class analysis and factor mixture modelling analysis.
Results
Different types of paranoid ideation ranged in frequency from less than 2% to nearly 30%. Total scores on these items followed an almost perfect exponential distribution (r = 0.99). Our four a priori first-order factors were corroborated (interpersonal sensitivity; mistrust; ideas of reference; ideas of persecution). These mapped onto four classes of individual respondents: a rare, severe, persecutory class with high endorsement of all item factors, including persecutory ideation; a quasi-normal class with infrequent endorsement of interpersonal sensitivity, mistrust and ideas of reference, and no ideas of persecution; and two intermediate classes, characterised respectively by relatively high endorsement of items relating to mistrust and to ideas of reference.
Conclusions
The paranoia continuum has implications for the aetiology, mechanisms and treatment of psychotic disorders, while confirming the lack of a clear distinction from normal experiences and processes.