Non-interpersonal measures

Some measures o f real-life problem-solving have assessed older people’s abilities to carry out everyday tasks. One study looked at food preparation, medication intake and telephone use, and compared performance on actually carrying out the tasks with a pen-and-paper version (Diehl, Willis Schaie, 1995). The measures were designed to all have an element o f inferential reasoning, and they found that increasing age was related to poorer performance. Performance was also related to fluid intelligence ability, which is perhaps not surprising given that the everyday measure was designed to assess reasoning. Indeed, performance was more strongly related to fluid intelligence ability than to age. There were good correlations between the real-life measure and the pen-and-paper measure, indicating that pen- and-paper methodology can potentially provide accurate information about real-life abilities. One issue that was not addressed was whether there were individual

differences in terms o f familiarity o f the tasks. For example, the food preparation tasks involved using a microwave oven and the study does not specify whether all participants were familiar with this method o f cooking.

The study reported above indicates that the nature o f the task may be important. This was addressed in another study that also looked at everyday domains, including medication use, financial planning, and food preparation/nutrition (Allaire and Marsiske, 1999). Within each domain there were various task demands that were designed to separately address reasoning, knowledge, working memory capacity, and declarative memory. They also included standardised measures purported to measure each o f these. They found that all abilities were associated with poorer performance with increasing age, with the exception o f those that were knowledge-based, which they interpreted as consistent with observations that crystallised intelligence is relatively preserved in older people. They also reported that the everyday and standardised measures in each domain were related to each other, although performance on the standardised measures also tended to relate to other domains in the real-life tasks, thus there was less specificity than they had predicted. This study highlights the fact that different results may be achieved depending on the types o f measures used. Overall, they suggested that basic abilities may remain constant during adulthood, but that levels o f competence beyond this, e.g. achieving optimal performance, may decline with age. They did not include a younger group for comparison across the age span.

Salthouse (1990a; 1990b) reviewed studies about age-related performance on practical everyday tasks. He argued that there is evidence that younger people perform better than older people on such tasks as remembering and dialling telephone numbers, and understanding labels on household items, and that declines in these abilities tends to be seen in the fifties and sixties. He also reported that, with regard to learning new skills, older people seem to need more practice than younger people. However, he speculated that perhaps it is the way people perform tasks that changes rather than overall competence. In support o f this, he cited studies looking at activities such as bridge and chess, which show that older people retain the global abilities, in the context o f poorer constituent skills. Thus,

experience may change the procedures by which older people solve everyday problems, and attempting to examine performance by breaking such tasks down into their constituent parts may be giving a biased and unduly pessimistic picture.

Other work has considered occupational skills. Denney (1989) argued that most o f the evidence regarding laboratory problem solving measures indicates that performance begins to decline after early adulthood. However, the general expectation is that middle-aged to older adults will perform better at occupational tasks than younger people. For example, people expect senior positions in fields such as finance, law and surgery to be held by people in the middle-aged to older age ranges, consistent with the greater experience these people have being more important than subtle decrements on laboratory measures. Colonia-Willner (1998) examined the relative importance o f experience and fluid intelligence on occupational performance in a sample o f bank managers. Experience was assessed both in terms o f number o f years in the post, and by use o f a standardised measure looking at ability to rank solutions in hypothetical management scenarios. She found that those people who were judged by the institution to have shown the best performance in their job, tended to be those with the greatest number o f years o f experience at the bank, although there was no difference in age between this group and the ‘nonexperts’. Within the nonexperts, those who were above the median age and who had high scores on the standardised measure o f managerial performance, nevertheless gained lower fluid intelligence scores. She argued that this group showed a normal age-related decrement on fluid intelligence, in the context of intact occupational problem solving ability. Overall, she claimed that practical knowledge can compensate for declines in ability with age. The main problem with making inferences about older people’s real-life abilities from this study is that the age range considered is obviously limited to those below retirement age.