Pleskac Timothy J, Wallsten Thomas S, Wang Paula, Lejuez C W
Department of Psychology, Michigan State University, East Lansing, MI 48824, USA.
Exp Clin Psychopharmacol. 2008 Dec;16(6):555-64. doi: 10.1037/a0014245.
Sequential risk-taking tasks, especially the Balloon Analogue Risk Task (BART), have proven powerful and useful methods in studying and identifying real-world risk takers. A natural index in these tasks is the average number of risks the participant takes in a trial (e.g., pumps on the balloons), but this is difficult to estimate because some trials terminate early because of the consequences of those risks (e.g., when the desired number of balloon pumps exceeds the explosion point). The standard corrective strategy is to use an adjusted score that ignores such event-terminated trials. Although previous data supports the utility of this adjusted score, the authors show formally that it is biased. Therefore, the authors developed an automatic response procedure, in which respondents state at the beginning of each trial how many risks they wish to take and then observe the sequence of events unfold. A study comparing this new automatic and the original manual BART shows that the automatic procedure yields unbiased statistics whereas maintaining the BART's predictive validity of substance use. The authors also found that providing respondents with the expected-value-maximizing strategy and complete trial-by-trial feedback increased the number of risks they were willing to take during the BART. The authors interpret these results in terms of the potential utility of the automatic version including shorter administration time, unbiased behavioral measures, and minimizing motor involvement, which is important in neuroscientific investigations or with clinical populations with motor limitations.
序贯冒险任务，尤其是气球模拟风险任务（BART），已被证明是研究和识别现实世界中冒险者的有力且有用的方法。这些任务中的一个自然指标是参与者在一次试验中承担风险的平均次数（例如，给气球打气的次数），但这很难估计，因为有些试验会因这些风险的后果而提前终止（例如，当所需的气球打气次数超过爆炸点时）。标准的校正策略是使用一个调整分数，该分数忽略此类因事件而终止的试验。尽管先前的数据支持这个调整分数的效用，但作者正式表明它存在偏差。因此，作者开发了一种自动反应程序，在该程序中，被试在每次试验开始时说明他们希望承担多少风险，然后观察事件的发展序列。一项比较这种新的自动版和原始手动版BART的研究表明，自动程序产生无偏差的统计数据，同时保持了BART对物质使用的预测效度。作者还发现，向被试提供期望值最大化策略和完整的逐次试验反馈会增加他们在BART期间愿意承担的风险数量。作者从自动版的潜在效用方面解释了这些结果，包括更短的施测时间、无偏差的行为测量以及将运动参与最小化，这在神经科学研究或对有运动限制的临床人群中很重要。
