Accuracy in discriminating blood glucose levels in a sample of children with type 1 diabetes

The present study explores accuracy in estimating blood glucose levels (BGL) in children with type 1 diabetes and analyzes the kinds of symptoms and cues which they use to estimate their BGL. Forty two children with type 1 diabetes completed a SI/IC-3 scale consisting of 28 items (22 symptoms and 6 feelings), indicating those which they perceived at the time and their intensity. They estimated their BGL and gave reasons for their estimation, before having a blood glucose level analysis performed. The results indicated great variability in the accuracy of estimating BGL. They showed failures in the correct discrimination of symptoms of hypoglycemia as well as the presence of false beliefs regarding indicative symptoms of hyperglycemia, and the absence of symptoms as an indicator for euglycemia, beliefs which provoke different and frequent errors in the estimation of BGL. Correct use of external signs is shown to be related to correct estimations of normal BGL, as well as hypoglycemia and hyperglycemia. We discuss the implications these results could have on designing psychological intervention procedures for diabetics in the form of training programs to discriminate BGL accurately, taking into account these findings and previous studies completed in the same field.     

Measuring patterns of change in personality assessments: an annotated application of latent growth curve modeling

Latent growth curve (LGC) modeling within the framework of structural equation modeling (SEM) is now highly regarded as one of the most powerful and informative approaches to the analysis of longitudinal data (see, e.g., Curran & Hussong, 2003). Whereas LGC modeling enables researchers to test for differences in developmental trajectories across time, conventional repeated measures analyses do not provide this opportunity. Nonetheless, a review of studies reported in most psychology journals reveals scant application of this methodological approach. One possible explanation for this limited use of LGC modeling is a lack of knowledge related to its application. The intent of this article, then, is to address this deficiency by presenting an annotated application of LGC modeling to health psychology data. Based on a sample of 405 Hong Kong Chinese women who recently underwent breast cancer surgery, we walk the readers through SEM modeling procedures that test for differences in both the initial status and rate of change in Psychological Morbidity and Social Adjustment at 1, 4, and 8 months postsurgery. We interpret findings from both a methodological and a substantive perspective.     

Self-regulation and recall: growth curve modeling of intervention outcomes for older adults

Memory training has often been supported as a potential means to improve performance for older adults. Less often studied are the characteristics of trainees that benefit most from training. Using a self-regulatory perspective, the current project examined a latent growth curve model to predict training-related gains for middle-aged and older adult trainees from individual differences (e.g., education), information processing skills (strategy use) and self-regulatory factors such as self-efficacy, control, and active engagement in training. For name recall, a model including strategy usage and strategy change as predictors of memory gain, along with self-efficacy and self-efficacy change, showed comparable fit to a more parsimonious model including only self-efficacy variables as predictors. The best fit to the text recall data was a model focusing on self-efficacy change as the main predictor of memory change, and that model showed significantly better fit than a model also including strategy usage variables as predictors. In these models, overall performance was significantly predicted by age and memory self-efficacy, and subsequent training-related gains in performance were best predicted directly by change in self-efficacy (text recall), or indirectly through the impact of active engagement and self-efficacy on gains (name recall). These results underscore the benefits of targeting self-regulatory factors in intervention programs designed to improve memory skills.     

Effects of a checklist on self-assessment of blood glucose level by a memory-impaired woman with diabetes mellitus

This study evaluated effects of a checklist on the accuracy of self-assessment of blood glucose level by a diabetic woman with memory impairments caused by viral encephalitis. The checklist consisted of 54 steps for operating an electronic glucometer, which the subject performed in sequence and checked off when completed. Following introduction of the checklist, the percentage of steps completed correctly increased in simulated and actual blood glucose tests and yielded clinically useful information.     

Lactate threshold prediction by blood glucose and rating of perceived exertion in people with type 2 diabetes

The validity of rating of perceived exertion (RPE) in predicting lactate threshold during an incremental test was analyzed in 15 men with type 2 diabetes (M age = 53.4 yr., SD = 12.9). Blood glucose, lactate, and minute ventilation (VE)/VO2 responses identified the lactate, ventilatory, and glucose thresholds. Workloads (W) corresponding to RPEs 12, 13, 14, and 15 were determined. Second-order polynomials fit to VE/W and [lac]/W ratios corresponding to RPEs of 9-10, 12-13, and 16-17 also identified workloads above which there was an overproportional increase in VE and [lac]. These workload breakpoints did not differ, although at RPE 12 underestimated and at RPE 15 overestimated lactate threshold. RPE 13 and 14 and the responses of VE/W and [lac]/W to submaximal exercise accurately predicted lactate threshold.     

Cognitive development of lead exposed children from ages 6 to 15 years: an application of growth curve analysis.

The effect of lead exposure on cognitive growth patterns was assessed in a longitudinal study of 196 children. Performances on tests of verbal comprehension and perceptual organization (Vocabulary & Block Design, Wechsler Intelligence Scales for Children) were measured at ages 6.5, 11 and 15 years. Growth curve analyses revealed that the quadratic model best described the relationship between test scores and age. Children with higher lead levels, as measured at age 15 years, demonstrated lower verbal comprehension scores over time and greater decline in their rate of Vocabulary development at age 15 years, as compared to children with lower lead levels. Lead exposure was not significantly associated with growth in perceptual organization test scores. Socioeconomic status and maternal intelligence were statistically significantly associated with growth patterns for both test scores, independent of the effects of lead. The findings suggest that lead negatively impacts the developmental progression of specific cognitive skills from childhood through adolescence.     

Neurodevelopmental outcomes of Ugandan infants with HIV infection: an application of growth curve analysis.

Neurodevelopmental outcomes of human immunodeficiency virus Type 1 (HIV-1)-infected infants of non-drug-using mothers were assessed in a controlled, prospective study from birth to 24 months with 3 groups: 61 infants of HIV-infected mothers, 234 uninfected infants of HIV-infected mothers (seroreverters), and 115 uninfected infants of uninfected mothers. Compared with seroreverters and uninfected infants, HIV-infected infants demonstrated lower mental and motor development on the Bayley Scales and greater deceleration in their rate of motor development. HIV-infected infants with abnormal neurologic exams had lower motor and mental test scores and lower rates of motor Bayley Scales scores than their HIV-infected counterparts with normal neurologic exams. Contrary to prediction, no group differences in mean performance or growth rates were found on visual information processing on the Fagan Test of Infant Intelligence.     

Attentional bias toward fear-related stimuli: an investigation with nonselected children and adults and children with anxiety disorders

Research investigating anxiety-related attentional bias for emotional information in anxious and nonanxious children has been equivocal with regard to whether a bias for fear-related stimuli is unique to anxious children or is common to children in general. Moreover, recent cognitive theories have proposed that an attentional bias for objectively threatening stimuli may be common to all individuals, with this effect enhanced in anxious individuals. The current study investigated whether an attentional bias toward fear-related pictures could be found in nonselected children (n=105) and adults (n=47) and whether a sample of clinically anxious children (n=23) displayed an attentional bias for fear-related pictures over and above that expected for nonselected children. Participants completed a dot-probe task that employed fear-related, neutral, and pleasant pictures. As expected, both adults and children showed a stronger attentional bias toward fear-related pictures than toward pleasant pictures. Consistent with some findings in the childhood domain, the extent of the attentional bias toward fear-related pictures did not differ significantly between anxious children and nonselected children. However, compared with nonselected children, anxious children showed a stronger attentional bias overall toward affective picture stimuli.     

The effects of a modeling film on social isolation in preschool children: A methodological investigation

Children in a Headstart program N=113) were assessed on two occasions using a naturalistic observation system and peer sociometric measures. Thirtytwo children were selected by O'Connor's (1969, 1972) convergent criteria of teacher rankings and being below 15% peer interaction frequency. Half of the children saw an experimental modeling film designed to teach children how to initiate entry into peer groups and half of the children saw a control film. The present investigation included methodological elements left uncontrolled in previous investigations. Results indicated no significant multivariate Fratios for treatment main effects, sociometric main effects, or treatment by sociometric interactions. This failure to replicate previous results with the O'Connor film raises serious methodological criticisms of previous work with socially withdrawn children.The author wishes to acknowledge the help of Jonni Gonso, Brian Rasmussen, and Phil Schuler in carrying out the data collection for this study. Thanks are also due for the invitation to do the research and the patience shown by the staff of Headstart, Bloomington, Indiana.     

Effects of video modeling on social initiations by children with autism

We examined the effects of a video modeling intervention on social initiation and play behaviors with 3 children with autism using a multiple baseline across subjects design. Each child watched a videotape showing a typically developing peer, and the experimenter engaged in a simple social interactive play using one toy. For all children, social initiation and reciprocal play skills were enhanced, and these effects were maintained at 1- and 3-month follow-up periods.     

Associations of blood glucose control with self-efficacy and rated anxiety/depression in type II diabetes mellitus patients

We investigated the possible relations of hemoglobin A1c (HbA1c) level, a parameter of blood glucose control with scores on anxiety, depression, and self-efficacy for 113 outpatients (55 men and 58 women) with type II diabetes mellitus. The relation between the HbA1c level and the self-efficacy scores as well as with the ratings of anxiety and depression was evaluated. A significant relation was found for the HbA1c level with the scores; however, self-efficacy and anxiety and depression showed no association. These results suggest that HbA1c can be maintained at better levels by increasing self-efficacy of diabetic patients.     

Implicit processing of emotional words by children with Post-Traumatic Stress Disorder: An fMRI investigation

Background/ObjectiveIn the last decade, socio-political violence in Colombia (South America) has created an environment of extreme/chronic stress. In this study, brain imaging technology (fMRI) and behavioral task performance were used to measure potential deficits in executive functioning for emotional processing in Colombian children.MethodParticipants (22 Post-Traumatic Stress Disorder, PTSD and 22 neurotypical, NT) were asked to perform a word task with implicit emotional salience, which required them to report the color of the ink in which a positive, negative or neutral word was printed.ResultsMixed design analysis of variance showed no group differences in accuracy for determining ink color when presented as a positive or neutral word. However, PTSD children were significantly less accurate (negative words) and notably slower (both positive and negative words) at determining ink color when presented in the context of an emotional word. PTSD processing of positive and negative words was associated with hypoactivation in the superior and middle frontal gyri of the right hemisphere in comparison to NT children.ConclusionsThese results may reflect a deficit in executive functioning for emotionally laden stimuli, perhaps induced as a by-product of their traumatic experiences.     

Selecting a linear mixed model for longitudinal data: repeated measures analysis of variance, covariance pattern model, and growth curve approaches

With increasing popularity, growth curve modeling is more and more often considered as the 1st choice for analyzing longitudinal data. Although the growth curve approach is often a good choice, other modeling strategies may more directly answer questions of interest. It is common to see researchers fit growth curve models without considering alterative modeling strategies. In this article we compare 3 approaches for analyzing longitudinal data: repeated measures analysis of variance, covariance pattern models, and growth curve models. As all are members of the general linear mixed model family, they represent somewhat different assumptions about the way individuals change. These assumptions result in different patterns of covariation among the residuals around the fixed effects. In this article, we first indicate the kinds of data that are appropriately modeled by each and use real data examples to demonstrate possible problems associated with the blanket selection of the growth curve model. We then present a simulation that indicates the utility of Akaike information criterion and Bayesian information criterion in the selection of a proper residual covariance structure. The results cast doubt on the popular practice of automatically using growth curve modeling for longitudinal data without comparing the fit of different models. Finally, we provide some practical advice for assessing mean changes in the presence of correlated data.     

A step away from impaired well-being: a latent growth curve analysis of an intervention with activity trackers among employees

ABSTRACT

The present study evaluated the effectiveness of a workplace intervention combining activity trackers (behavioural approach) with an online coach (cognitive approach) in order to increase employees’ number of steps and improve their impaired well-being (i.e., emotional strain and negative affect). To analyse the intervention’s effectiveness, the study applied latent growth curve modelling. Moreover, we tested whether work-related and personal resources (i.e., job control and self-efficacy) moderated the intervention’s effectiveness and whether an increase in number of steps was associated with an improvement in impaired well-being. During the intervention, data were collected at six measurement points from 108 mainly low active employees. The results revealed that employees increased their number of steps until the second intervention week; this increase was not moderated by job control or self-efficacy. Moreover, the intervention was effective in decreasing emotional strain and negative affect over the course of the intervention. Further analyses showed that the increase in number of steps was related to the decrease in negative affect, whereas no such association was found for the increase in number of steps and the decrease in emotional strain. In conclusion, the findings showed that our intervention was effective in improving physical activity and impaired well-being among employees.     

Identifying trajectories of adolescent smoking: an application of latent growth mixture modeling.

The goal of the current study was to identify discrete longitudinal patterns of change in adolescent smoking using latent growth mixture modeling. Five distinct longitudinal patterns were identified. A group of early rapid escalators was characterized by early escalation (at age 13) that rapidly increased to heavy smoking. A pattern characterized by occasional puffing up until age 15, at which time smoking escalated to moderate levels was also identified (late moderate escalators). Another group included adolescents who, after age 15, began to escalate slowly in their smoking to light (0.5 cigarettes per month) levels (late slow escalators). Finally, a group of stable light smokers (those who smoked 1-2 cigarettes per month) and a group of stable puffers (those who smoked only a few puffs per month) were also identified. The stable puffer group was the largest group and represented 25% of smokers.     

Facilitating cognitive performance in children: A comparison of strategy modeling and strategy modeling with overt self-verbalization

Children, 3, 4, 5, 6, 8, and 10 years old, were randomly divided into three training conditions—a strategy modeling condition, a strategy modeling with overt self-verbalization condition, and a control condition. The subjects in the two modeling conditions were given training on four cognitive tasks, a signal task, a match-to-standard task, a paired-associates task, and a twenty-questions task. A 6 (age) × 2 (sex) × 3 (treatment) × 2 (trial) analysis of variance was performed on each of the dependent variables associated with each of the four tasks. The results of these analyses indicate that both modeling conditions facilitated performance on the signal and match-to-standard tasks for all six age groups. However, the two modeling procedures facilitated performance on the paired-associates and twenty-questions tasks only in the three older age groups. Since the two modeling procedures did not differ in effectiveness, it was suggested that strategy modeling without overt self-verbalization is the more practical and efficient procedure for facilitating cognitive performance in normal children.     

Growth curve models for indistinguishable dyads using multilevel modeling and structural equation modeling: the case of adolescent twins' conflict with their mothers

Growth modeling is a useful tool for studying change over time, and it is becoming increasingly popular with developmental researchers. There is a considerable methodological literature surrounding growth modeling for individuals; however, far less attention has been focused on growth models for pairs of related individuals (i.e., dyads). In this article, the authors consider dyadic growth models for those cases where there are no relevant variables that can empirically distinguish between dyad members (e.g., same-sex twins or best friends). The authors describe how researchers can estimate growth models for indistinguishable dyads using both multilevel modeling and structural equation modeling. Although both approaches can be used to estimate the same underlying models, the authors focus on practical similarities and differences between the two approaches. They illustrate modeling issues using an overtime study of adolescent twins' conflict with their mothers, a substantively important topic given the enduring interest in parent-child relationships during adolescence.     

EMG and motor performance changes with practice of a forearm movement by children

The purpose of this research was to investigate changes in the control of movement, using EMG and kinematic variables, over practice by children. Children in three age groups, 7, 9, and 11 yr., performed 60 trials of an elbow-flexion movement. Correct movements consisted of a 60 degrees angular movement of the forearm in 800 msec. The analysis of biceps brachii and triceps brachii muscle EMG activity, movement displacement and timing error, and movement velocity patterns indicated changes in motor performance with practice. All age groups improved performance with practice and also exhibited a decrease in biceps EMG activity with practice. Only movement-time error and time to peak triceps muscle activity differed between the age groups. The 11-yr.-old group significantly altered the timing of the antagonistic response to stop the movement over the practice session. This change is suggested to be related to the greater information-processing ability of these children and the development of appropriate movement strategies to perform the movement task successfully. Other changes observed in the EMG data appear similar to changes observed in studies of adults.