It is well recognized that depression and anxiety are closely associated, but nonetheless, they may be associated with distinct causes and consequences. For example, anxiety and depression are associated with different effects on information processing. This paper argues that experiments should not study anxiety or depression in isolation, but should measure both variables. It is argued that this methodological step is both important and commonly overlooked. Even when both depression and anxiety are measured, methodological difficulties can confuse their effects. Common difficulties in choice of measures and in participant selection criteria are discussed, and recommendations are made for overcoming them. The argument is made drawing from illustrations within the experimental cognitive literature, but conclusions and recommendations are equally applicable outside this area.

中文翻译：

---

焦虑和抑郁：为什么以及如何衡量他们各自的影响。

众所周知，抑郁症和焦虑症密切相关，但它们可能与不同的原因和后果有关。例如，焦虑和抑郁与对信息处理的不同影响相关。本文认为，实验不应孤立地研究焦虑或抑郁，而应同时测量这两个变量。有人认为，这种方法学步骤既重要又被普遍忽视。即使同时测量了抑郁和焦虑，方法论上的困难也可能混淆其效果。讨论了措施选择和参与者选择标准中的常见困难，并提出了克服这些困难的建议。该论点是根据实验性认知文献中的插图得出的，