Friis S, Larsen T K, Melle I, Opjordsmoen S, Johannessen J O, Haahr U, Simonsen E, Rund B R, Vaglum P, McGlashan T
Division of Psychiatry, Ullevål University Hospital, Oslo, Norway.
Acta Psychiatr Scand. 2003 Jan;107(1):3-9. doi: 10.1034/j.1600-0447.2003.02600.x.
To identify and discuss methodological pitfalls that may help explain why many questions around early detection (ED) and duration of untreated psychosis (DUP) are still unsolved.
This paper concentrates on pitfalls in the following areas: sampling, measurement and data analyses.
The main problems seem to be:
Referral bias, exclusion of patients, patient refusal, and patients lost to follow-up.
Reliability, which is particularly cogent for multisite investigations, and validity, which includes: Start of illness, start of psychosis, diagnoses, start of treatment, the relationship between ED and DUP and choice of outcome measures. Data Analyses: Overlooking threshold effects of DUP, improper control for baseline scores, and lack of control for confounders.
Methodological pitfalls may bias ED studies. Several pitfalls are unavoidable, but proper design and quality assurance can reduce their impact. Researchers ought to identify the pitfalls, and to estimate and discuss their influence.
识别并探讨可能有助于解释为何围绕早期发现（ED）和未治疗精神病持续时间（DUP）的诸多问题仍未得到解决的方法学陷阱。
本文聚焦于以下领域的陷阱：抽样、测量和数据分析。
主要问题似乎包括：
转诊偏倚、患者排除、患者拒绝以及失访患者。
可靠性（对于多中心研究尤为关键）和有效性，有效性包括：疾病起始、精神病起始、诊断、治疗起始、ED与DUP之间的关系以及结局测量指标的选择。数据分析：忽视DUP的阈值效应、对基线分数控制不当以及未对混杂因素进行控制。
方法学陷阱可能使ED研究产生偏差。一些陷阱难以避免，但合理的设计和质量保证可降低其影响。研究人员应识别这些陷阱，并评估和讨论其影响。
