Participants viewed a simulated crime and attempted an identification from an 8-person target-present or target-absent lineup. The authors examined identification confidence-accuracy relations, contrasting a control condition (n = 310) with 2 manipulations designed to improve confidence scaling. Before indicating confidence, participants reflected on encoding and identification test conditions (n = 316) or suggested hypotheses about why their identification decision might have been wrong (n = 318). Confidence-accuracy correlations were weak and did not differ across conditions. However, for positive identifications, confidence and accuracy were well calibrated in the experimental conditions, although not in the control condition; similar patterns were observed for lineup rejections. Explanations for calibration differences in terms of discrimination difficulty, (mis)match between encoding and test stimuli, and the availability of confidence cues were advanced.

Data are reported from 3,213 research eyewitnesses confirming that accurate eyewitness identifications from lineups are made faster than are inaccurate identifications. However, consistent with predictions from the recognition and search literatures, the authors did not find support for the "10-12-s rule" in which lineup identifications faster than 10-12 s maximally discriminate between accurate and inaccurate identifications (D. Dunning & S. Perretta, 2002). Instead, the time frame that proved most discriminating was highly variable across experiments, ranging from 5 s to 29 s, and the maximally discriminating time was often unimpressive in its ability to sort accurate from inaccurate identifications. The authors suggest several factors that are likely to moderate the 10-12-s rule.

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Purpose. Children who witness crimes are sometimes asked to view a photospread lineup to see if they can identify the culprit. Here, we examined the effectiveness of two manipulations designed to assist in overcoming the tendency of child eyewitnesses to choose from lineups, a tendency that manifests in false identifications from target‐absent lineups. Methods. Children aged around 12 years (N = 432) were randomly assigned to control, Not Sure, or accuracy motivation conditions in order to examine both target‐absent and ‐present identification test performance across multiple sets of stimulus materials. Results. The Not Sure option did not affect false alarms or hit rates, but the combination of accuracy motivating conditions and the Not Sure option reduced guessing, with overall rates of false identifications falling by 12.2%. The latter effect was much stronger under some stimulus conditions but not detectable under others, indicating that the manipulations could improve but not impair performance. While there were beneficial effects at the group level, the manipulation did not produce a general change in individual children's decision strategies. Conclusions. Eyewitness identification test manipulations that reliably reduce false alarms, without lowering hits, by child witnesses have not yet been identified. Here, we showed how a simple‐to‐implement accuracy motivation manipulation reduces false alarms under some conditions, while also highlighting the importance of evaluating the efficacy of interventions across varied encoding and test conditions. However, developing a procedure that can produce a generalized improvement in decision making at the individual level remains a major challenge for eyewitness researchers.

A . K EA S T A ND T .V . R I LE Y. 1997. The 'string' test has been described as a test for the initial characterization of Vibrio spp., in particular, to differentiate between Vibrio and Aeromonas spp. Despite early literature questioning the validity of the test, its use has continued to be recommended. In this study, 49 Vibrio spp., 32 Aeromonas spp. and 47 enteric Gram-negative bacilli were tested and it was found that four genera gave a positive 'string' test, including Vibrio, Aeromonas, Pseudomonas and Klebsiella. The sensitivity and specificity of the test for separating Vibrio spp. from other Gram-negative bacilli were 86% and 70%, respectively. Hence the use of the string test in the initial characterization of Vibrio spp. should be supported by appropriate confirmatory tests.