Hawthorne Graeme, Mouthaan Joanne, Forbes David, Novaco Raymond W
Australian Centre for Posttraumatic Mental Health, Dept. of Psychiatry, University of Melbourne, Melbourne, Australia.
Soc Psychiatry Psychiatr Epidemiol. 2006 Feb;41(2):164-72. doi: 10.1007/s00127-005-0986-y. Epub 2006 Jan 1.
Anger is a key long-term outcome from trauma exposure, regardless of trauma type, and it is implicated as a moderator of response to treatment. It therefore seems important that anger is assessed in both epidemiological studies of trauma sequelae and in intervention evaluation research. This study explored the measurement properties of a recently investigated anger scale, the Dimensions of Anger Reactions (DAR) Scale. In our previous study, the DAR was found to be a measure of trait anger, but although brief, the nine response categories per item may have confused respondents, suggesting fewer response categories may work equally well. Additionally, our previous analysis suggested there were two redundant items within the DAR.
Three samples of Australian veterans were used to investigate the psychometric properties associated with alterations to the response categories of the DAR; veterans who participated in the DAR validation study, those participating in group therapy programmes for post-traumatic stress disorder, and veterans participating in lifestyle programmes. Item response theory analysis was used to explore the internal properties of competing DAR models, and models were assessed against external criteria.
The results showed that the number of item responses in the DAR exceeded channel capacity, and that response bias occurred in the second half of the instrument. We hypothesized that this was due to respondents not discriminating among the many response categories. Based on a modelling exercise in which we reduced the number of DAR items from 7 to 5 and the number of response categories from 9 to 5, validation tests showed that there was no loss of sensitivity, reliability or validity. To avoid confusion with the DAR, we have referred to the revised version of the DAR as the DAR5.
We conclude that the DAR5, which abbreviates the original DAR to half its original length, has similar psychometric properties and is therefore to be preferred especially for use with persons who are under stress, cognitively impaired or less mature. The study findings regarding the optimum number of response categories have implications for the development of other instruments.
愤怒是创伤暴露后的一个关键长期后果，无论创伤类型如何，并且它被认为是治疗反应的一个调节因素。因此，在创伤后遗症的流行病学研究和干预评估研究中评估愤怒似乎都很重要。本研究探讨了最近研究的一种愤怒量表——愤怒反应维度（DAR）量表的测量特性。在我们之前的研究中，发现DAR是一种特质愤怒的测量工具，但尽管简短，每个项目的九个反应类别可能会使受访者感到困惑，这表明较少的反应类别可能同样有效。此外，我们之前的分析表明DAR中有两个冗余项目。
使用三组澳大利亚退伍军人样本，来研究与DAR反应类别改变相关的心理测量特性；参与DAR验证研究的退伍军人、参与创伤后应激障碍团体治疗项目的退伍军人以及参与生活方式项目的退伍军人。项目反应理论分析用于探索竞争的DAR模型的内部特性，并根据外部标准对模型进行评估。
结果表明，DAR中的项目反应数量超过了通道容量，并且在量表后半部分出现了反应偏差。我们假设这是由于受访者无法区分众多反应类别所致。基于一项建模练习，我们将DAR项目数量从7个减少到5个，反应类别数量从9个减少到5个，验证测试表明敏感性、可靠性或有效性均未丧失。为避免与DAR混淆，我们将修订后的DAR版本称为DAR5。
我们得出结论，DAR5将原始DAR缩写至其原始长度的一半，具有相似的心理测量特性，因此尤其适用于处于压力下、认知受损或不太成熟的人群。关于最佳反应类别数量的研究结果对其他工具的开发具有启示意义。
