Clinical Research Unit for Anxiety and Depression, School of Psychiatry, University of New South Wales, St Vincent's Hospital, Sydney, Australia.
Int Psychogeriatr. 2012 Feb;24(2):231-42. doi: 10.1017/S1041610211001852. Epub 2011 Sep 21.
Old age respondents may differ systemically in their responses to measures of psychological distress over and above their actual latent distress levels when compared to younger respondents. The current study aimed to investigate the potential for age-related bias(es) in the Kessler 6 Psychological Distress Scale (K6) items.
Data from the 2007 Australian National Survey of Mental Health and Wellbeing were analyzed using Item Response Theory to detect the presence of item bias in each of the K6 items. The potential for item bias was assessed by systematically comparing respondents classed as young (16-34 years), middle aged (35-64 years), and old aged (65-85 years). The significance and magnitude of the item bias between the age groups was assessed using the log-likelihood ratio method of differential item functioning.
After statistical adjustment, there were no biases of significant magnitude influencing the endorsement of K6 items between young and middle-aged respondents or between middle-aged and old age respondents. There was a bias of significant magnitude present in the endorsement of the K6 item addressing levels of fatigue between young and old age respondents.
Despite the identification of significant item bias in the endorsement of K6 items between the age groups, the magnitude and influence of the bias on total K6 scores is likely to have little influence on the overall interpretation of group data when comparing psychological distress across the lifespan. Researchers should be cautious, however, when examining individual levels of fatigue related to psychological distress in older individuals.
与年轻受访者相比，老年受访者在回答心理困扰测量时，除了实际的潜在困扰水平外，可能在系统上存在差异。本研究旨在调查 Kessler 6 心理困扰量表（K6）项目中与年龄相关的偏差（s）的可能性。
使用项目反应理论对 2007 年澳大利亚国家心理健康和幸福感调查的数据进行分析，以检测 K6 各项中是否存在项目偏差。通过系统比较被归类为年轻（16-34 岁）、中年（35-64 岁）和老年（65-85 岁）的受访者，评估项目偏差的可能性。使用差异项目功能的对数似然比方法评估年龄组之间项目偏差的显著性和大小。
经过统计调整，在年轻和中年受访者之间或中年和老年受访者之间，没有显著大小的偏差影响 K6 项目的认可。在年轻和老年受访者对疲劳程度的 K6 项目认可方面存在显著的偏差。
尽管在年龄组之间 K6 项目的认可方面存在显著的项目偏差，但偏差对总 K6 分数的大小和影响可能对跨生命周期比较心理困扰时的总体组数据解释影响不大。然而，当研究人员检查与老年人心理困扰相关的个体疲劳水平时，应谨慎行事。
