Editors can lead researchers to confidence intervals, but can't make them think: statistical reform lessons from medicine

Since the mid-1980s, confidence intervals (CIs) have been standard in medical journals. We sought lessons for psychology from medicine's experience with statistical reform by investigating two attempts by Kenneth Rothman to change statistical practices. We examined 594 American Journal of Public Health (AJPH) articles published between 1982 and 2000 and 110 Epidemiology articles published in 1990 and 2000. Rothman's editorial instruction to report CIs and not p values was largely effective: In AJPH, sole reliance on p values dropped from 63% to 5%, and CI reporting rose from 10% to 54%; Epidemiology showed even stronger compliance. However, compliance was superficial: Very few authors referred to CIs when discussing results. The results of our survey support what other research has indicated: Editorial policy alone is not a sufficient mechanism for statistical reform. Achieving substantial, desirable change will require further guidance regarding use and interpretation of CIs and appropriate effect size measures. Necessary steps will include studying researchers' understanding of CIs, improving education, and developing empirically justified recommendations for improved statistical practice.     

Evaluation of the Computerized Assessment System for Psychotherapy Evaluation and Research (CASPER) as a measure of treatment effectiveness with psychiatric inpatients

Assessment procedures to evaluate inpatient treatment effectiveness can provide information to inform clinical practice. The Computerized Assessment System for Psychotherapy Evaluation and Research (CASPER) represents a standardized approach to assess patients' target problems that combines elements of individualized and nomothetic approaches. Although previous evaluations of CASPER with other patient populations have been encouraging, its use as a measure of change with an inpatient population has not been examined. In this study, 75 psychiatric inpatients completed CASPER and the Behavior and Symptom Identification Scale-32 (BASIS-32) at hospital admission and discharge. Results supported the concurrent validity of CASPER as a measure of pre- and posttreatment functioning and suggested that CASPER may provide a sensitive measure of change during inpatient treatment. Findings also supported the notion that patients' ratings of the extent to which their treatment focused on the problems they identified as a high priority were related to their overall treatment satisfaction.     

The Impact of the Built Environment on Children’s School Conduct Grades: The Role of Diversity of Use in a Hispanic Neighborhood

A population-based study examined the relationship between diversity of use of the built environment and teacher reports of children’s grades. Diversity of use of the built environment (i.e., proportion of a block that is residential, institutional, commercial and vacant) was assessed for all 403 city blocks in East Little Havana, Miami—a Hispanic neighborhood. Cluster analysis identified three block-types, based on diversity of use: Residential, Mixed-Use, and Commercial. Cross-classified hierarchical linear modeling was used to examine the impact of diversity of use, school, gender, and year-in-school on academic and conduct grades for 2857 public school children who lived in these blocks. Contrary to popular belief, mixed-use blocks were associated with optimal outcomes. Specifically, follow-up analyses found that a youth living on a residential block had a 74% greater odds of being in the lowest 10% of conduct grades (conduct GPA <2.17) than a youth living on a mixed-use block. In fact, an analysis of the population attributable fraction suggests that if the risk associated with residential blocks could be reduced to the level of risk associated with mixed-use blocks, a 38% reduction in Conduct GPAs <2.17 could be achieved in the total population. These findings suggest that public policy targeting the built environment may be a mechanism for community-based interventions to enhance children’s classroom conduct, and potentially related sequelae.     

Nonconscious temporal cognition: Learning rhythms implicitly

Two experiments demonstrate that people can implicitly learn rhythms. Participants responded to a series of fast-paced beeps by pressing a key as soon as possible after each beep. They were not told that the duration (180, 450, or 1,125 msec) between each keypress and the next beep was specified by a repeating sequence. In both experiments, participants responded significantly faster to predictable, sequenced timing than to random timing but did not show more knowledge of the sequence than did control participants on explicit memory measures. This dissociation was obtained even with an explicit memory test in Experiment 2 that maintained the same context and response metric as the implicit task to maximize the transfer of relevant knowledge. Implications for temporal cognition are discussed.     

Duration processing in children as determined by time reproduction: implications for a few seconds temporal window

From research carried out over recent years using different experimental paradigms, it has become apparent that central information processing is temporally segmented into sequential units of a few seconds. This segmentation presumably reflects a neuronal process of temporal integration (TI) which automatically binds successive events into temporal units. Support for such TI comes, for example, from studies on temporal reproduction where standards up to approximately 2-3 s are reproduced veridically. Using this paradigm of temporal reproduction, we investigated the effect of normal cognitive development of sensory modality and of the range of presented standards on TI. Sixty children aged 6-7, 9-10 and 13-14 years reproduced visual or auditory standard durations ranged from 1 to 5.5 s or from 1 to 3 s. The results showed that durations of approximately 2 s were reproduced correctly, whereas those longer than 2.5 s were under-reproduced in the three age groups. For standards shorter than 2 s substantial age-related differences were revealed: the youngest group displayed significant over-reproduction comparing to older subjects. These observations indicate that the upper limit for TI is a stable feature across the different age groups. Furthermore an age-related modulation within the temporal window of the operating TI seems to be linked to cognitive development.     

Visual aids and structured criteria for improving visual inspection and interpretation of single-case designs

Because behavior analysis is a data-driven process, a critical skill for behavior analysts is accurate visual inspection and interpretation of single-case data. Study 1 was a basic study in which we increased the accuracy of visual inspection methods for A-B designs through two refinements of the split-middle (SM) method called the dual-criteria (DC) and conservative dual-criteria (CDC) methods. The accuracy of these visual inspection methods was compared with one another and with two statistical methods (Allison & Gorman, 1993; Gottman, 1981) using a computer-simulated Monte Carlo study. Results indicated that the DC and CDC methods controlled Type I error rates much better than the SM method and had considerably higher power (to detect real treatment effects) than the two statistical methods. In Study 2, brief verbal and written instructions with modeling were used to train 5 staff members to use the DC method, and in Study 3, these training methods were incorporated into a slide presentation and were used to rapidly (i.e., 15 min) train a large group of individuals (N = 87). Interpretation accuracy increased from a baseline mean of 55% to a treatment mean of 94% in Study 2 and from a baseline mean of 71% to a treatment mean of 95% in Study 3. Thus, Study 1 answered basic questions about the accuracy of several methods of interpreting A-B designs; Study 2 showed how that information could be used to increase the accuracy of human visual inspectors; and Study 3 showed how the training procedures from Study 2 could be modified into a format that would facilitate rapid training of large groups of individuals to interpret single-case designs.     

One size does not fit all: Exploring how the five-factor model facets predict disordered eating behaviours among adolescent and young adult males and females

There is a wealth of research that has highlighted the relationship between personality and eating disorders. It has been suggested that understanding how subclinical disordered eating behaviours are uniquely associated with personality can help to improve the conceptualization of individuals with eating disorders. This study aimed to explore how the facets of the Five-Factor Model (FFM) predicted restrictive eating, binge eating, purging, chewing and spitting, excessive exercising and muscle building among males and females. An online survey assessing disordered eating behaviours, FFM and general psychopathology was completed by 394 females and 167 males aged between 16 and 30 years. Simultaneous equations path models were systematically generated for each disordered eating behaviour to identify how the FFM facets, body dissatisfaction and age predicted behaviour. The results indicated that each of the six disordered behaviours were predicted by a unique pattern of thinking, feeling and behaving. Considerable differences between males and females were found for each path model, suggesting differences between males and females in the personality traits that drive disordered eating behaviours. It was concluded that it is important to take personality into account when treating males and females who engage in disordered eating behaviours.     

Depressive thoughts limit working memory capacity in dysphoria

Dysphoria is associated with persistence of attention on mood-congruent information. Longer time attending to mood-congruent information for dysphoric individuals (DIs) detracts from goal-relevant information processing and should reduce working memory (WM) capacity. Study 1 showed that DIs and non-DIs have similar WM capacities. Study 2 embedded depressive information into a WM task. Compared to non-DIs, DIs showed significantly reduced WM capacity for goal-relevant information in this task. Study 3 replicated results from Studies 1 and 2, and further showed that DIs had a significantly greater association between processing speed and recall on the depressively modified WM task compared to non-DIs. The presence of inter-task depressive information leads to DI-related decreased WM capacity. Results suggest dysphoria-related WM capacity deficits when depressive thoughts are present. WM capacity deficits in the presence of depressive thoughts are a plausible mechanism to explain day-to-day memory and concentration difficulties associated with depressed mood.     

What are the combined effects of negative emotions and illness cognitions on self-care in people with type 2 diabetes? A longitudinal structural equation model

Objective: To explore whether negative emotions mediate the effect of diabetes cognitions on diabetes self-care and conversely whether diabetes cognitions mediate the effect of negative emotions on diabetes self-care.

Design: Longitudinal observational study in adults with type 2 diabetes.

Main outcome measures: Self-reported depression and anxiety (Diabetes Wellbeing Questionnaire), cognitions (Illness Perceptions Questionnaire-Revised; Beliefs about Medicines Questionnaire), and diabetes self-care (Summary of Diabetes Self-Care Activities Scale) were completed at baseline and six months. Analyses used structural equation modelling.

Results: Baseline medication concerns were associated with elevated symptoms of depression and anxiety at follow-up, but emotions did not mediate medication concern’s effect on diabetes self-care. Baseline depression and anxiety symptoms were associated with specific diabetes cognitions over time, but these cognition domains did not mediate emotion’s effect on diabetes self-care. Personal control remained independent of emotions and was associated with diabetes self-care over time.

Conclusions: Negative emotions did not act directly or alongside cognitions to influence diabetes self-care. The reciprocal relationship between diabetes cognitions and emotions suggests cognitive restructuring, in addition to other mood management intervention techniques would likely improve the emotional wellbeing of adults with type 2 diabetes. Likewise, personal control beliefs are likely important intervention targets for improving self-care.