Decision support aids with anthropomorphic characteristics influence trust and performance in younger and older adults

This study examined the use of deliberately anthropomorphic automation on younger and older adults' trust, dependence and performance on a diabetes decision-making task. Research with anthropomorphic interface agents has shown mixed effects in judgments of preferences but has rarely examined effects on performance. Meanwhile, research in automation has shown some forms of anthropomorphism (e.g. etiquette) have effects on trust and dependence on automation. Participants answered diabetes questions with no-aid, a non-anthropomorphic aid or an anthropomorphised aid. Trust and dependence in the aid was measured. A minimally anthropomorphic aide primarily affected younger adults' trust in the aid. Dependence, however, for both age groups was influenced by the anthropomorphic aid. Automation that deliberately embodies person-like characteristics can influence trust and dependence on reasonably reliable automation. However, further research is necessary to better understand the specific aspects of the aid that affect different age groups. Automation that embodies human-like characteristics may be useful in situations where there is under-utilisation of reasonably reliable aids by enhancing trust and dependence in that aid. Practitioner Summary: The design of decision-support aids on consumer devices (e.g. smartphones) may influence the level of trust that users place in that system and their amount of use. This study is the first step in articulating how the design of aids may influence user's trust and use of such systems.     

Medication schemas and memory for automated telephone messages

The present study investigated whether older and younger adults use a schema to organize and remember spoken reminder messages for taking medication. Previous research has shown that older and younger adults share preferences for organizing printed instructions for taking medication, suggesting a shared schema. Older and younger participants in Experiment 1 of the present study used a similar schema to organize medication reminder messages. This finding suggests that the medication schema generalizes across communication purpose (to remind or to instruct) as well as across patient age. Medication reminder messages were better understood and remembered when organized to match this schema, whether the reminders were presented as automated telephone messages (Experiment 2) or in printed form (Experiment 3). Schema-compatible organization especially helped people draw inferences from the messages, suggesting that organization helps older and younger adults construct a situation model of the medication-taking task from the messages. Potential applications of organized messages include increasing the impact of automated systems for delivering health services.     

The role of trust in automation reliance

A recent and dramatic increase in the use of automation has not yielded comparable improvements in performance. Researchers have found human operators often underutilize (disuse) and overly rely on (misuse) automated aids (Parasuraman and Riley, 1997). Three studies were performed with Cameron University students to explore the relationship among automation reliability, trust, and reliance. With the assistance of an automated decision aid, participants viewed slides of Fort Sill terrain and indicated the presence or absence of a camouflaged soldier. Results from the three studies indicate that trust is an important factor in understanding automation reliance decisions. Participants initially considered the automated decision aid trustworthy and reliable. After observing the automated aid make errors, participants distrusted even reliable aids, unless an explanation was provided regarding why the aid might err. Knowing why the aid might err increased trust in the decision aid and increased automation reliance, even when the trust was unwarranted. Our studies suggest a need for future research focused on understanding automation use, examining individual differences in automation reliance, and developing valid and reliable self-report measures of trust in automation.     

Effects of age, speech rate, and environmental support in using telephone voice menu systems

Age differences in the use of telephone menu systems were investigated in two experiments. Participants from three age groups (younger: 18-39; middle-aged: 40-59; older: 60+ years) were required to obtain specified information or perform some action using simulated voice menu systems. Measures reflecting task performance, menu navigation, and subjective responses were collected. The focus in Experiment 1 was on examining the effect of speech rate. Data from 196 participants indicated age differences in performance, especially for complex problems. There was no effect of speech rate on any of the performance measures. Experiment 2 examined two types of support devices: a screen phone and a graphical aid. Data from 114 participants indicated that the screen phone provided some benefits in navigational efficiency. In terms of performance, the older participants benefited more from the graphical aid and the younger participants performed better with the screen phone. Actual or potential applications of this research include guidance in the use of support devices that can reduce memory demands and the identification of appropriate speech rates.     

Automation failures on tasks easily performed by operators undermine trust in automated aids

OBJECTIVE: We tested the hypothesis that automation errors on tasks easily performed by humans undermine trust in automation. BACKGROUND: Research has revealed that the reliability of imperfect automation is frequently misperceived. We examined the manner in which the easiness and type of imperfect automation errors affect trust and dependence. METHOD: Participants performed a target detection task utilizing an automated aid. In Study 1, the aid missed targets either on easy trials (easy miss group) or on difficult trials (difficult miss group). In Study 2, we manipulated both easiness and type of error (miss vs. false alarm). The aid erred on either difficult trials alone (difficult errors group) or on difficult and easy trials (easy miss group; easy false alarm group). RESULTS: In both experiments, easy errors led to participants mistrusting and disagreeing more with the aid on difficult trials, as compared with those using aids that generated only difficult errors. This resulted in a downward shift in decision criterion for the former, leading to poorer overall performance. Misses and false alarms led to similar effects. CONCLUSION: Automation errors on tasks that appear "easy" to the operator severely degrade trust and reliance. APPLICATION: Potential applications include the implementation of system design solutions that circumvent the negative effects of easy automation errors.     

Using icons to convey medication schedule information

We examined older adult comprehension and memory for medication schedules conveyed by different types of visual icons as well as text. Three icons were compared: a timeline, a pair of 12 h clocks (one for AM and one for PM hours) and a 24 h clock. In Experiment 1, older and younger participants paraphrased and then recalled schedules that were conveyed by the three icons or by text. Text and timeline schedules were paraphrased more accurately than either clock icon. Paraphrase errors suggested that subjects had trouble integrating schedule information across the two 12 h clocks. Analysis of paraphrase times showed that the text schedule was paraphrased most quickly, followed by the timeline, the 24 h clock and the 12 h clock. No differences were found for the accuracy of recalling the icon and text schedules. Experiment 2 examined free and cued recall after limited study time by older adults. Because text superiority in Experiment 1 may have reflected greater familiarity with text than with icons, recall was examined across four trials in Experiment 2. Text was recalled most accurately, followed by the timeline, the 24 h clock and the 12 h clock. Study-test trials did not influence recall. Text schedules may have been generally more effective than the icons because of their greater familiarity. The timeline may have been the most effective icon because it was more compact and familiar than the clock icons used in the study. The findings suggest that including such icons in medication instructions requires training.     

Understanding sources of user variability in computer-based data entry performance

The pervasive use of computers in work settings implies that an increased number of workers, with varying levels of skills and abilities, will be performing computerbased tasks. This study investigated the impact of age, cognitive abilities, and computer experience on the performance of a real world data entry task. One hundred and ten subjects, ranging in age from 20 - 75 years, performed the task for nine hours following task training. The results indicated that abilities such as visuo-spatial skills, motor skills and processing speed had a significant impact on performance as did age and prior computer experience. With respect to age, the older participants completed less work than the younger and middle-aged subjects. Age differences in psychomotor skills and processing speed appeared to be important factors underlying age effects. In fact, the data indicated that after controlling for differences in these abilities age was no longer a significant predictor of work output. Further, after controlling for differences in work output the older people made fewer errors than the younger people. Overall the data suggest that older people will be at a disadvantage in the performance of computer-based data entry work to the extent to which speed of responding is emphasized. However, if speed of responding is not a critical element of performance they will be able to achieve comparable levels of performance to that of younger people.     

Understanding sources of user variability in computer-based data entry performance

The pervasive use of computers in work settings implies that an increased number of workers, with varying levels of skills and abilities, will be performing computerbased tasks. This study investigated the impact of age, cognitive abilities, and computer experience on the performance of a real world data entry task. One hundred and ten subjects, ranging in age from 20 - 75 years, performed the task for nine hours following task training. The results indicated that abilities such as visuo-spatial skills, motor skills and processing speed had a significant impact on performance as did age and prior computer experience. With respect to age, the older participants completed less work than the younger and middle-aged subjects. Age differences in psychomotor skills and processing speed appeared to be important factors underlying age effects. In fact, the data indicated that after controlling for differences in these abilities age was no longer a significant predictor of work output. Further, after controlling for differences in work output the older people made fewer errors than the younger people. Overall the data suggest that older people will be at a disadvantage in the performance of computer-based data entry work to the extent to which speed of responding is emphasized. However, if speed of responding is not a critical element of performance they will be able to achieve comparable levels of performance to that of younger people.     

Automation in future air traffic management: effects of decision aid reliability on controller performance and mental workload

Future air traffic management concepts envisage shared decision-making responsibilities between controllers and pilots, necessitating that controllers be supported by automated decision aids. Even as automation tools are being introduced, however, their impact on the air traffic controller is not well understood. The present experiments examined the effects of an aircraft-to-aircraft conflict decision aid on performance and mental workload of experienced, full-performance level controllers in a simulated Free Flight environment. Performance was examined with both reliable (Experiment 1) and inaccurate automation (Experiment 2). The aid improved controller performance and reduced mental workload when it functioned reliably. However, detection of a particular conflict was better under manual conditions than under automated conditions when the automation was imperfect. Potential or actual applications of the results include the design of automation and procedures for future air traffic control systems.     

Touch a screen or turn a knob: choosing the best device for the job

Input devices enable users to interact with systems. In two experiments, we assessed whether and how task demands and user age influenced task performance for a direct input device (touch screen) and an indirect input device (rotary encoder). In Experiment 1, 40 younger (18-28 years) and 40 middle-aged to older adults (51-65 years) performed tasks using controls such as sliders, up/down buttons, list boxes, and text boxes while using a system. The optimal input device to facilitate performance was dependent on the task being performed and the age of the user. In Experiment 2, touch screen use was assessed for 20 younger (19-23 years) and 20 older adults (51-70 years). Task demands were manipulated through button size, movement distance, direction, and type of movement. Performance was moderated by the age of the user and by task demands. Actual or potential applications of this research include guidance for the optimal selection of input devices for different user populations and task characteristics.     

Light pen use and practice minimize age and hand performance differences in pointing tasks

We contrasted performance with mouse and light pen input devices for younger, middle-aged, and older adults (N = 72) who were experienced mouse users. Participants used both preferred and nonpreferred hands to perform a menu target selection task. The light pen minimized age differences in performance relative to the mouse. Older adults were more lateralized on a handedness test than young adults and were less efficient using their nonpreferred hand. With practice, older adults improved their response time more than other age groups did. The mouse was rated as more acceptable and easier to use than the light pen across trials, despite the performance advantage of the light pen for all age groups. Usability ratings correlated moderately with performance. A benefit-cost analysis indicated that the more efficient light pen might cover its greater initial cost within 11 months for an older adult and within 23 months for a younger adult. Actual or potential applications of this research include advising older adults to persist with practice for new input devices, advising those who must switch to their non-preferred hand to select a direct positioning device, and providing a methodology for determining the potential payback interval when switching to a faster, though more expensive, input device.     

The effect of risk on trust attitude and trust behavior in interaction with information and decision automation

Situational risk has been postulated to be one of the most important contextual factors affecting operator’s trust in automation. However, experimentally, it has received only little attention and was directly manipulated even less. To close this gap, this study used a virtual reality multi-task environment where the main task entailed making a diagnosis by assessing different parameters. Risk was manipulated via the altitude, the task was set in including the possibility of virtually falling in case of a mistake. Participants were aided either by information or decision automation. Results revealed that trust attitude toward the automation was not affected by risk. While trust attitude was initially lower for the decision automation, it was equally high in both groups at the end of the experiment after experiencing reliable support. Trust behavior was significantly higher and increased during the experiment for the decision automation supported group in the form of less automation verification behavior. However, this detrimental effect was distinctly attenuated under high risk. This implies that negative consequences of decision automation in the real world might have been overestimated by studies not incorporating risk.

     

Misuse of automated decision aids: Complacency, automation bias and the impact of training experience

The present study investigates automation misuse based on complacency and automation bias in interacting with a decision aid in a process control system. The effect of a preventive training intervention which includes exposing participants to rare automation failures is examined. Complacency is reflected in an inappropriate checking and monitoring of automated functions. In interaction with automated decision aids complacency might result in commission errors, i.e., following automatically generated recommendations even though they are false. Yet, empirical evidence proving this kind of relationship is still lacking. A laboratory experiment (N=24) was conducted using a process control simulation. An automated decision aid provided advice for fault diagnosis and management. Complacency was directly measured by the participants’ information sampling behavior, i.e., the amount of information sampled in order to verify the automated recommendations. Possible commission errors were assessed when the aid provided false recommendations. The results provide clear evidence for complacency, reflected in an insufficient verification of the automation, while commission errors were associated with high levels of complacency. Hence, commission errors seem to be a possible, albeit not an inevitable consequence of complacency. Furthermore, exposing operators to automation failures during training significantly decreased complacency and thus represents a suitable means to reduce this risk, even though it might not avoid it completely. Potential applications of this research include the design of training protocols in order to prevent automation misuse in interaction with automated decision aids.     

Using a checklist-based electronic calculation aid and contextual cues to assist medication dose calculation and calculation resumption after interruptions

ObjectivesTo examine whether (1) the use of a checklist-based electronic calculation aid enhanced medication dose calculation and reduced the negative effects of interruptions on calculation, and (2) the use of contextual cues facilitated the resumption of calculation after an interruption.MethodsSixty students in healthcare majors participated in two computer-based laboratory experiments. Experiment 1 examined the effects of the calculation aid and interruptions on calculation error rate, calculation completion time, and perception outcomes. Experiment 2 assessed the effects of contextual cues on resumption error rate, calculation error rate, calculation completion time, and perception outcomes.ResultsIn Experiment 1, calculation error rates were lower for participants who received the calculation aid versus those who did not, and for uninterrupted calculations versus interrupted calculations, although the differences were not statistically significant.The participants spent significantly less time completing the calculation task with the use of the calculation aid than without the use of the calculation aid, and in the case without interruptions than in the case with interruptions. In Experiment 2, the use of contextual cues associated with previous actions significantly reduced the resumption error rate and the completion time of the medication dose calculation. Both experiments showed that the use of the calculation aid and contextual cues was associated with positive attitudes toward the aid and cues, reduced mental effort, and/or higher confidence in task performance.ConclusionsThe use of the checklist-based electronic calculation aid and contextual cues facilitated medication dose calculation and resumption after interruptions and thus has the potential to improve medication safety and work efficiency in healthcare.     

Age differences in visual search for traffic signs during a simulated conversation

The effects of divided attention were examined in younger adults (M = 23 years) and older adults (M = 64 years) who searched for traffic signs in digitized images of traffic scenes. Sign search was executed under single-task and dual-task conditions in scenes containing either small or large amounts of visual clutter. For both age groups, clutter and the secondary task had additive effects on search accuracy, speed, and oculomotor involvement. Compared with the younger adults, older adults were less accurate, especially with high-clutter scenes, were slower to decide that a target sign was not present, and exhibited a marginally greater divided-attention effect on reaction times. They exhibited longer fixations in the divided-attention condition, in which they also showed a disproportionate reduction in recognition memory for the content of the secondary task. Actual or potential applications of this research include methods for evaluating the distraction of conversations and safety implications of conversation on visual search behavior.     

A framework for explaining reliance on decision aids

This study presents a framework for understanding task and psychological factors affecting reliance on advice from decision aids. The framework describes how informational asymmetries in combination with rational, motivational and heuristic factors explain human reliance behavior. To test hypotheses derived from the framework, 79 participants performed an uncertain pattern learning and prediction task. They received advice from a decision aid either before or after they expressed their own prediction, and received feedback about performance. When their prediction conflicted with that of the decision aid, participants had to choose to rely on their own prediction or on that of the decision aid. We measured reliance behavior, perceived and actual reliability of self and decision aid, responsibility felt for task outcomes, understandability of one's own reasoning and of the decision aid, and attribution of errors. We found evidence that (1) reliance decisions are based on relative trust, but only when advice is presented after people have formed their own prediction; (2) when people rely as much on themselves as on the decision aid, they still perceive the decision aid to be more reliable than themselves; (3) the less people perceive the decision aid's reasoning to be cognitively available and understandable, the less people rely on the decision aid; (4) the more people feel responsible for the task outcome, the more they rely on the decision aid; (5) when feedback about performance is provided, people underestimate both one's own reliability and that of the decision aid; (6) underestimation of the reliability of the decision aid is more prevalent and more persistent than underestimation of one's own reliability; and (7) unreliability of the decision aid is less attributed to temporary and uncontrollable (but not external) causes than one's own unreliability. These seven findings are potentially applicable for the improved design of decision aids and training procedures.     

Manual dexterity of older Mexican American adults: a cross-sectional pilot experimental investigation

This paper reports results from an experimental pilot study performed to quantify the manual dexterity of older Mexican American adults. The Purdue pegboard test, a two-arm coordination test, and a hand-tool dexterity test were used in this study. To enable cross-sectional comparisons of manual dexterity measures of older Mexican American adults with young Mexican American adults, these tests were administered to 18 older Mexican American adults aged 63–85 (mean age: 71.3 years, SD: 7.0 years), recruited from senior recreation centers in El Paso, and eighteen young adults aged 21–32 (mean age: 25.6 years, SD: 3.8 years) recruited from the student body at the University of Texas at El Paso. For the Purdue pegboard test, the number of pegs placed in 30 s using the preferred hand, the non-preferred hand, and both hands were first individually monitored. Then, scores on an assembly task using the Purdue pegboard were obtained. For the two-arm coordination test, participants were required to trace a star pattern with a stylus using both hands. The time for task completion and the number of errors made during task performance were monitored. For the hand-tool dexterity test, participants were required to use common hand tools and remove nuts and bolts from one side of a wooden upright, and to assemble nuts and bolts in the corresponding holes on the other side of the upright. The time taken for task completion was recorded. Since modified Levene's test showed equality of variances, two sample t-tests, comparing the mean responses of older adults with the mean responses of young adults for each individual test, were conducted. Results indicate that responses for the older adults were statistically significant different (p<0.001) from young adults for all Purdue pegboard tasks. On the average, older adults performed significantly slower (p<0.001) than young adults on the two-arm coordination test, and committed more errors before task completion (p<0.05). Older adults also took longer to complete the hand-tool dexterity task compared to their younger counterparts (p<0.05). In addition to the t-tests, manual dexterity performance measures from older adults were regressed with age to determine the cross-sectional age effects on manual dexterity measures. Results indicate that all Purdue pegboard performance measures were significantly affected by age (p<0.05). The time to complete the two-arm coordination test was significantly linearly related to age (p<0.05). However, the number of errors committed by older adults in the performance of the two-arm coordination test was not significantly linearly related to age. Time to complete the hand-tool dexterity was also significantly linearly related to age (p<0.05). Accommodating age-related changes in manual dexterity is important for job design in industry, especially in industries employing older adults requiring significant assembly and hand-tool use.

Relevance to industry

Given the aging of the industrial workforce, it is important to understand how manual dexterity is affected by age, so that jobs requiring significant manual dexterity for task initiation, task performance and task completion are designed to fit older adult dexterity levels.     

Age-related differences in warning symbol comprehension and training effectiveness: effects of familiarity, complexity, and comprehensibility

Age-related changes in selective attention, inhibitory efficiency, and the ability to form new associations suggest that older adults may have greater difficulty with more complex and less comprehensible symbols. We examined comprehension of symbols varying in terms of ratings of familiarity, complexity, and comprehensibility, by younger (aged 18-35) and older (aged 55-70) adults. It was found that older adults have greater difficulty than younger adults in comprehending warning symbols and that accident scenario training improves comprehension. Regression analyses indicated that familiarity and comprehensibility were important in determining performance on the pre-training comprehension test by both younger and older adults. However, training eliminated the effects of stimulus characteristics for younger adults, while older adults' comprehension continued to be significantly influenced by comprehensibility. We suggest that symbol design incorporates cues to knowledge to facilitate the linkage between new knowledge (i.e. the warning symbol) and relevant knowledge in long-term memory. Statement of Relevance: Symbol characteristics play an important role in age-related differences in warning symbol comprehension. To optimise comprehension by older adults, symbols should have a clear relationship with areal-world referent. Alternatively, symbol design could incorporate cues to knowledge to facilitate the linkage between new knowledge and relevant knowledge in long-term memory.     

Imaginal technology and management information processing: a review of the applied literature

The present study examined the reactions of older and younger workers to the situation of encountering an error during computer-based work. It was expected that older workers would have a stronger negative emotional reaction to such an error due to a combination of age-related factors. In both a questionnaire and an observational study among 134 office workers this was found to be the case. This age relationship remained after controlling for differences in computer experience, attitudes to new technology, education and the number of errors made by participants during a typical computer-based work session. More detailed analyses showed that in response to an error situation, older workers compared to younger ones stated they were significantly less likely to try and solve the problem entirely on their own; this was also partly supported by the observational data. In terms of the available options for helping rectify errors, older workers reported that they were more often likely to use written documentation and rely less on asking other workers. The implications of the findings are discussed in terms of interventions to ameliorate the impact of errors in computer-based work on an older workforce.