Informant-Based Determinants of Symptom Attenuation in Structured Child Psychiatric Interviews

Informant-related determinants of item attenuation, that is, the drop-off in symptom endorsement rates at retest, were examined in an enriched community subsample of 245 parent–child pairs drawn from the National Institute of Mental Health Methods for Epidemiology of Child and Adolescent Mental Disorders Study. Youngsters and their parents were interviewed with the Diagnostic Interview Schedule for Children (Version 2.3; DISC-2.3) on two occasions with a mean test–retest interval of 12 days. Item attenuation rates were high for both informants, with adults failing to confirm 42% and children 58% of baseline responses at retest. Stepwise regressions revealed that item attenuation at DISC-P retest was higher for adult informants who were younger, and who reported on older and less impaired children. On the DISC-C, attenuation was higher for children who were less impaired, rated as doing worse in school, and who had a longer test–retest interval. These results are broadly consistent with past studies examining the determinants of attenuation and test–retest reliability and have implications for the design and use of structured diagnostic instruments.     

Diversity and substitutability of adjunctive activities under fixed-interval schedules of food reinforcement

Six rats received food contingent on pressing a lever on fixed-ratio 1, fixed-interval 30-second, and fixed-interval 60-second schedules, with concurrent access to a drinking spout, a running wheel, and a block of wood. Drinking, running, and chewing were monitored automatically, and these and other activities were observed directly during selected sessions. Because all sessions ended after delivery of 60 pellets, total time available for activities other than eating increased over the three schedules. Time spent contacting the lever and visiting the food tray increased in proportion to total available time, whereas the time spent in other activities changed in a complex manner such that drinking was the dominant adjunctive behavior in the 30-second condition, and running or chewing the dominant adjunctive behavior in five of six rats in the 60-second condition. General activity and grooming also occupied significant amounts of time. In a subsequent part of the experiment, running and chewing were prevented, and the majority of other activities, especially drinking and grooming, increased. The results show that (a) FI schedules of food reinforcement are accompanied by a wide variety of adjunctive activities; (b) the preferred activity differs according to the schedule duration; and (c) the extent to which activities substitute for one another is limited by the tendency for different activities to occupy different parts of the interreinforcement interval.     

Behaviour of Rats During Selfinitiated Pauses in Feeding and Drinking, and During Periodic Response-Independent Delivery of Food and Water

In Experiment I rats deprived of either food or water were given free access to food or water respectively, and their behaviour was observed during self-imposed pauses in feeding or drinking. In Experiment II food or water were delivered according to fixed-time 30-s and fixed-time 60-s schedules, and the behaviour of the rats was observed during the interreinforcement intervals imposed by these schedules. In both experiments the temporal pattern of those activities that occurred during pauses in eating differed from the pattern of activities occurring during pauses in drinking; and with both food and water the temporal pattern of activities during self-imposed pauses in consummatory behaviour in Experiment I proved a good predictor of the pattern of activities during schedule-imposed interreinforcement intervals in Experiment II. This suggests that intermittent schedules permit the occurrence of those activities that are normally closely associated with the consummatory behaviour in question. In Experiment II certain activities that occurred towards the end of the interreinforcement interval were found to be enhanced relative to baseline level, but there was no enhancement of activities occurring near the beginning of the interval. This is contrary to Staddon's (1977) account of schedule-induced behaviour, and suggests that schedule-induction is not as common as has sometimes been supposed.     

Some relationships between behavioral and traditional assessment

Psychometric principles and procedures were developed within the context of traditional approaches to assessment. In order to illustrate the frequent, if not uniform, applicability of these principles to behavior assessment, we first discuss the differences and similarities between traditional and behavioral assessment. We then point out ways in which, given the nature of behavior assessment, attention to certain psychometric principles and procedures would expedite the development of more adequate behavior assessment devices and procedures.     

Are schedule-induced drinking and displacement activities causally related?

The acquisition of schedule-induced drinking was studied in hungry rats given food according to an intermittent (fixed-time 45-s) schedule, in three separate experiments. Rate of acquisition of induced drinking was not affected by making the rats thirsty as well as hungry (Experiment I), nor by offering them a palatable saline solution instead of water (Experiment II). Thirst and palatability did affect the asymptotic level of induced drinking. Increasing the level of food deprivation (Experiment III) increased both the rate of acquisition of induced drinking and its asymptotic level. Thus, rate of acquisition of induced drinking was found to depend more on causal factors relevant to feeding than on causal factors relevant to drinking, while asymptotic level of drinking was affected by both types of causal factor. This suggests that the occurrence of induced drinking does not depend primarily on a disinhibition mechanism of the type thought to underlie displacement activities, and hence does not support the idea that induced drinking is a type of displacement activity.     

Most directed forgetting in pigeons can be attributed to the absence of reinforcement on forget trials during training or to other procedural artifacts.

In research on directed forgetting in pigeons using delayed matching procedures, remember cues, presented in the delay interval between sample and comparisons, have been followed by comparisons (i.e., a memory test), whereas forget cues have been followed by one of a number of different sample-independent events. The source of directed forgetting in delayed matching to sample in pigeons was examined in a 2 x 2 design by independently manipulating whether or not forget-cue trials in training ended with reinforcement and whether or not forget-cue trials in training included a simultaneous discrimination (involving stimuli other than those used in the matching task). Results were consistent with the hypothesis that reinforced responding following forget cues is sufficient to eliminate performance deficits on forget-cue probe trials. Only when reinforcement was omitted on forget-cue trials in training (whether a discrimination was required or not) was there a decrement in accuracy on forget-cue probe trials. When reinforcement is present, however, the pattern of responding established during and following a forget cue in training may also play a role in the directed forgetting effect. These findings support the view that much of the evidence for directed forgetting using matching procedures may result from motivational and behavioral artifacts rather than the loss of memory.     

Comparability and validity of computerized adaptive testing with the MMPI-2

The comparability and validity of a computerized adaptive (CA) Minnesota Multiphasic Personality Inventory-2 (MMPI-2) were assessed in a sample of 571 undergraduate college students. The CA MMPI-2 administered adaptively Scales L, E the 10 clinical scales, and the 15 content scales, utilizing the countdown method (Butcher, Keller, & Bacon, 1985). All subjects completed the MMPI-2 twice, with three experimental conditions: booklet test-retest, booklet-CA, and conventional computerized (CC)-CA. Profiles across administration modalities show a high degree of similarity, providing evidence for the comparability of the three forms. Correlations between MMPI-2 scales and other psychometric measures (Beck Depression Inventory; Symptom Checklist-Revised; State-Trait Anxiety and Anger Scales; and the Anger Expression Scale) support the validity of the CA MMPI-2. Substantial item savings may be realized with the implementation of the countdown procedure.     

Scales,diagnoses, and child psychopathology: II. Comparing the CBCL and the DISC against external validators

Using a multimethod multistage screening procedure, the authors interviewed 201 parents and their children with the Diagnostic Interview Schedule for Children (DISC 2.1). In addition, parents completed the Child Behavior Checklist (CBCL) and other survey measures, while their children completed self-report scales. Receiver operating characteristic (ROC) analyses were done to determine optimal cutpoints on the CBCL, referenced to DISC diagnostic caseness. DISC diagnoses, DISC stem symptoms, CBCL scores, and CBCL ROC-cutpoints were compared against external validators, in order to determine the comparative advantages of each approach for assessing child psychopathology. Overall findings suggest that the controversies about best assessment strategies may be artificial: When both assessment approaches are compared using similar methods, they are reasonably comparable. However, highly specific diagnostic categories may show fewer relationships with external validators and may therefore need more systematic validational studies.The opinions and assertions contained in this paper are the private views of the authors and are not to be construed as official or as reflecting the views of the Department of Health and Human Services, the National Institute of Mental Health, the Walter Reed Army Institute of Research, or the Department of the Army.     

Comparability of computerized adaptive and conventional testing with the MMPI-2

A computerized adaptive version and the standard version of the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) were administered 1 week apart to a sample of 155 college students to assess the comparability of the two versions. The countdown method was used to adaptively administer Scales L, F, the I0 clinical scales, and the 15 new content scales. Profiles across administration modalities show a high degree of similarity, providing evidence for the comparability of computerized adaptive and conventional testing with the MMPI-2. Substantial item savings were found with the adaptive version. Future directions in the study of adaptive testing with the MMPI-2 are discussed.