Meaningfully improved mental and behavioral health treatment is an unrealized dream. Across three factorial experiments, inferential tests in prior studies showed a pattern of negative interactions, suggesting that better clinical outcomes may be obtained when participants receive fewer rather than more intervention components. Furthermore, relatively few significant main effects were found in these experiments. Modeling suggested that negative interactions among components may account for these patterns. In this article, we evaluate factors that may contribute to such declining benefit: increased attentional or effort burden; components that produce their effects via the same capacity-limited mechanisms, making their effects subadditive; and a tipping-point phenomenon in which people near a hypothesized tipping point for change will benefit markedly from weak intervention and people far from the tipping point will benefit little from even strong intervention. New research should explore factors that cause negative interactions among components and constrain the development of more effective treatments.

有意义地改善心理和行为健康治疗是一个未实现的梦想。在三个析因实验中，先前研究中的推理测试显示出一种负面相互作用的模式，这表明当参与者接受更少而不是更多的干预成分时，可以获得更好的临床结果。此外，在这些实验中发现的显着主效应相对较少。建模表明，组件之间的负面相互作用可能是造成这些模式的原因。在本文中，我们评估了可能导致这种效益下降的因素：注意力或努力负担增加；通过相同的容量限制机制产生效果的组件，使其效果具有亚累加性；以及一种临界点现象，即接近假设的变革临界点的人们将从弱干预中显着受益，而远离临界点的人们即使从强有力的干预中也几乎受益匪浅。新的研究应该探索导致成分之间产生负面相互作用并限制更有效治疗方法开发的因素。