Intrasubject Design Research Articles

ADHD Rating Scale-IV en una muestra escolar española: datos normativos y consistencia interna para maestros, padres y madres

The ADHD Rating Scale-IV (ADHD RS-IV) is one of the most use scales for attention deficit hyperactivity disorder (ADHD), because has cut-off point regarding age, gender and setting, but the normalization data is based on American school samples. Evaluation of cut-off point of ADHD-RS-IV for parents and teachers in a Spanish sample. The study used the score of ADHD-RS-IV from a prevalence study of ADHD in school children of 6-12 years. Using an intrasubject design between the three evaluators (parents and teachers) and the results of each subscale (IN, H/I, and TOT) according to gender and age factors. Then, we analyzed the reliability and internal consistency for each subscale and evaluator. There are no significant differences between the father and the mother; but there are between teachers, and father and/or mother scores. In relation to gender factor, boys' score is higher on inattention and hyperactivity-impulsivity than girls'. Our results show a reversal tendency in comparison with the American samples, in our case parents' scores were significantly higher than teachers'. The use and normalization of the ADHD RS-IV will need to account not only for age, gender and setting but also for socio-cultural aspects.

Sex differences in cardiac and autonomic response to clinical and experimental pain in LBP patients

Rehabilitation professionals are currently using heart rate (HR) in order to assess the sincerity of effort in certain evaluations. It has been shown that a relation exists between HR and pain but no study has measured cardiac response during both clinical and experimental pain among a patient population using an intra-subject design. Thirty patients with low back pain (LBP) participated in this study including 16 men. Clinical pain was induced by applying a postero-anterior pressure (PA) on a painful lumbar segment for 15 and 30 s in order to reproduce the patient’s typical LBP at an intensity ranging between 50 and 70/100. Experimental pain was induced with a 15 s thermal stimulus at a temperature which reproduced the same pain intensity as the 15 s PA. For both reproduced clinical pain durations, we observed a rise in HR ranging between 8.5% and 12.67%. However, unlike men, women’s cardiac response failed to show a constant rise in HR during the 30 s PA. For all subjects, the rise in HR was much lower during the experimental pain condition ( p < 0.001), reaching only 5%. On the other hand, galvanic skin responses were significantly higher during the experimental pain condition ( p < 0.001). During this same condition, women also had a greater rise in galvanic skin responses than men ( p = 0.04). Finally, a significant correlation was found between both types of pain. These results suggest that pain induced during a clinical evaluation will produce a significant HR augmentation. However, heart rate variability analysis showed greater sympathetic cardiac regulation for men. The sex differences observed in this study call for caution when interpreting HR during pain assessment.

From methodology to data analysis: Prospects for the n = 1 intrasubject design

The target article is important not only for black-box studies, but also for those interested in tracing cognitive processing and/or subjective experience (via systematic self-observation). I provide two examples taken from my own research. I then proceed to discuss how best to analyze data from the n = 1 study, which has a factorial design.

Blood Glucose Discrimination Training: The Role of Internal and External Cues

The effects of observing internal and external events on blood glucose (BG) discrimination were assessed in eight patients with type 1 diabetes using an intrasubject design. During baseline condition, participants estimated their BG, then measured and recorded it (feedback-only procedure) three times a day. Participants were then divided randomly into two groups. Both were submitted to internal cue (IC) and external cue (EC) training conditions in a balanced order, and then both cues were presented together in combined cues (CC) training conditions. Under IC, participants observed and recorded their symptoms before estimating BG. Under EC, they observed and recorded environmental events prior to BG estimation. In CC conditions, participants paid attention to both internal and external cues before the estimate-feedback routine. BG estimation accuracy improved after either IC or EC conditions. When the two types of cues were combined, only two participants improved their BG estimation accuracy. The remainder did not, probably because they had already attained high accuracy levels (ceiling effect).

The effect of paroxetine on 5-HT(2A) receptors in depression: an [(18)F]setoperone PET imaging study.

In the cortex of animals, serotonin (5-HT) levels increase after several weeks of treatment with selective serotonin reuptake inhibitors (SSRIs). Studies using an intrasubject design to examine the effects of SSRI treatment on 5-HT(2A) receptors in the cortex of drug-free depressed patients are needed. In theory, agonist stimulation of 5-HT(2A) receptors could be relevant to SSRI treatment by promoting neuronal growth and survival as well as direct elevation of mood. The objective of this study was to evaluate the effect of 6 weeks of paroxetine treatment on 5-HT(2A) receptors in depressed patients. After a medication-free period of at least 3 months, 19 depressed patients were treated for 6 weeks with paroxetine, 20 mg/day. The authors used [(18)F]setoperone and positron emission tomography to assess 5-HT(2A) receptor binding potential in the patients before and after treatment and in 19 age-matched healthy subjects. 5-HT(2A) binding potential declined with age in all cortical regions in the depressed and healthy subjects. There was a significant interaction between age and treatment effect on 5-HT(2A) binding potential in all cortical regions. Subjects aged 20 to 30 years had a 10% decrease in 5-HT(2A) binding potential after treatment, whereas subjects aged 30 to 40 had no change. No regional differences in 5-HT(2A) binding potential between depressed and healthy subjects were found. 5-HT(2A) receptors down-regulate in young depressed subjects after treatment with paroxetine, but this down-regulation attenuates with age. This suggests that over 6 weeks paroxetine treatment increases 5-HT agonism on 5-HT(2A) receptors in the cortex of young patients with depression.

Quantitative assessment of response shift in QOL research

Two assumptions which characterize the measurements of quality life (QOL) studies, are questioned by the present report: First, the assumption that QOL is the same thing for all subjects, is usually related to health problems and can easily be measured across subjects. Second, when this assumption is given up by introducing subjective base-rates in an intra-subject (before-after) design, researchers still tend to assume that no response shifts occur on the QOL scales, e.g., that these scales maintain the same meaning and values for subjects over time and interventions. In our study we found that QOL had different subjective interpretations [1--4]. While for some certain issues in their family-life determined their quality of life, for others these were issues at their workplace or of their health conditions. Second, when QOL was tested against a subjective base-line (for each individual according to their choices of domains), about eleven percent of the hypertensives and normotensives showed a clear response shift of scale-calibration over the period of one year. When the scores of these subjects were excluded, the significance of certain previously reported results changed. For example, the significant difference between normotensives and hypertensives concerning the change in their subjective evaluation of QOL over the year and their initial depression became more significant, while similar changes in their evaluation of sexual impairment and control at their work-place became insignificant. These results suggest that response shifts have to be traced and quantified, before one can claim any results (or lack of results) in 'before-after' designs, concerning subjective meaningful issues like quality of life.

Progesterone Reduces Immobility in Rats Forced to Swim

Background Among its behavioral actions, progesterone reduces anxiety in several species including humans; however, any antidepressant-like properties remain to be explored. Methods In the present study, Wistar rats received injections (i.p.) of progesterone (0.20–3.0 mg/kg) 24 and 2 h before being submitted to the forced swim, a test in which antidepressants regularly reduce immobility and exert few or no actions on locomotor activity. In order to discard the cumulative effects of progesterone and a possible effect from the repetition of the swimming test, all animals received one of several progesterone doses in a different sequence following a completely randomized experimental intrasubject design. Results Ovariectomy did not modify immobility in the forced swim test as compared to control tests practiced before surgery. A dose of 0.80 mg/kg strongly reduced the total time of immobility in forced swim test ( p <0.001), but did not modify locomotor activity. In a drug-free control test applied 1 week after the last injection of progesterone, immobility returned to the higher values observed in the control tests. Conclusions From these results, it is concluded that progesterone may possess some antidepressant-like activity.

The Generalisation of Cognitive Behavioural Marital Therapy in Behavioural, Cognitive and Physiological Domains

The limited effectiveness of cognitive behavioural marital therapy (CBMT) for some couples may be due to a failure to achieve generalized changes in behavioural, cognitive or physiological responses during marital interaction. In the present study an intra-subject replication design across five maritally distressed couples assessed changes associated with CMBT in behaviour, cognitions, and physiological arousal during marital communication. These response domains were assessed weekly in both clinic and home settings. Introduction of CBMT was associated with clear reductions in behavioural negativity in both settings for all couples, some variable cognitive changes across couples and settings, but no consistent change in physiological arousal across couples or settings. Physiological responding was asynchronous with behaviour and cognition. Further research is needed on the significance of physiological arousal in marital distress, and the importance of changes in physiological responding during marital interaction to marital therapy outcome.

Using Computers to Increase the Social Interactions of Preschoolers with Disabilities at Community-based Sites

Integrated programs promote social skill development for children with disabilities. Environments promoting social interactions between children are necessary to facilitate such development. The following study demonstrates that the combination of two environments, the community-based preschool classroom and the computer, results in an increase in positive peer-to-peer interactions, higher social participation, and more verbal initiations by children with disabilities. Social interactions of young children with disabilities were measured while using computers with nondisabled peers. A rotating ''focal-child'' observation system was used to study the effect, of interventions on five children with disabilities within the mainstreamed preschool setting. Four specific behaviors were scored during interactions using interval recordings. An intrasubject replication design was employed within a multiple treatment reversal form. Results support the validity of the computer procedures as ones which enhance social interaction rates of young children with disabilities. The implications of these findings are discussed.

EMG-activated feedback alarms for the treatment of nocturnal bruxism: current status and future directions.

This article reviews published research on the use of EMG-activated feedback paradigms to modify nocturnal bruxism. The first three sections review naturalistic trials, laboratory studies, and comparisons of feedback paradigms with alternative treatment/management approaches. The fourth section overviews several sources of theoretical guidance for further research and delineates some substantive directions. The final section identifies major scientific shortcomings that are common in the literature and offers some correctives. The empirical reviews suggest that nocturnal bruxing feedback is beneficial and competitive with other approaches, particularly when the feedback serves to occasion behaviors that require wakefulness. The theoretical overview points to classical learning theories, biofeedback theories, and theories concerning the etiology of bruxism as guideposts for continued research. The methodological narrative calls for adequately detailed scientific reporting, for increased operational commonality across experiments, and for innovative integrations of actuarial and intrasubject research designs.

A Methodology for the Quantitative Synthesis of Intra-Subject Design Research

Investigators using quantitative synthesis methodology have as yet been unable to include the results from single-case experiments in their analyses, in large part because of the lack of a suitable statistical methodology. The development of a regression model that can be used to generate effect sizes for both changes in slope and changes in level occurring as a result of the treatment intervention is outlined. Analysis of lag one autocorrelation among the residuals suggests that serial correlation is not a serious problem. The regression approach provides a satisfactory fit of the data, and may thus provide a basis for the generation of effect sizes from single-case experimental data.

An intrasubject replication strategy for evaluating occlusal splint therapy.

AbstractOkeson and others have proposed that statistical comparisons between groups of treated and untreated patients be used to evaluate the effectiveness of occlusal splint therapy. This article argues that valid between-groups comparisons cannot be made by most clinicians and that such comparisons do not satisfactorily guide the treatment of individual patients. An intrasubject replication design strategy is then offered as a model for clinicians to use in evaluating splint-therapy effects in individual cases.

Intrasubject experimental designs in osteopathic medicine: Applications in clinical practice

Intrasubject experimental designs in osteopathic medicine: Applications in clinical practice

Review articles for continuing education in pharmacology

The efficacy of educational review articles as alternatives to traditional continuing education courses in pharmacology was evaluated using pre-tests and post-tests and an intrasubject cross-over design. There was a significant improvement (p less than 0.001) from pre-test to post-test in a group of 44 subjects who read an article reviewing the clinical pharmacology of nitrous oxide. This observation suggests that educational review articles may be useful as adjuncts to traditional sources of information for continuing education in pharmacology.

Microanalysis of action and fear arousal as a function of differential levels of perceived self-efficacy.

Two experiments combining intergroup and intrasubject designs were conducted to test the hypothesis that self-percepts of efficacy operate as cognitive mediators of coping behavior and fear arousal. Differential levels of self-efficacy were induced in phobic subjects through either inactive mastery or modeling. Their coping behavior and accompanying fear arousal were then measured. In the next phase, self-efficacy was successively raised to designated levels within the same subjects, whereupon their behavior and fear arousal were again measured. Coping behavior corresponded closely to instated self-percepts of efficacy, with higher levels of perceived self-efficacy being accompanied by greater performance attainments. The efficacy-action relationship was replicated across different modes of efficacy induction, different types of behavioral dysfunctions, and in both intergroup and intrasubject comparisons. The hypothesis that fear arousal stems largely from perceived coping inefficacy also received support from the findings. As subjects' self-efficacy level was raised, they experienced progressively less anticipatory and performance distress while coping with threats. Results of a third experiment using cardiac acceleration and elevation in blood pressure as indicants of arousal further corroborate the generality of the relationship between perceived coping inefficacy and stress reactions.

Stimulus control over sex-typed play in cross-gender identified boys

Discriminative stimulus control over masculine and feminine sex-typed play behaviors was investigated in five boys, aged 5–8 yr, with “childhood crossgender identification.” Reliable observational measures of play were obtained with two sets of toys: (a) “dress-up toys” (girls' apparel vs boys' apparel), and (b) “affect toys” (maternal-nurturance play vs masculine-aggression play). With an ABA reversal intrasubject design, certain stimulus conditions (e.g., presence of father, mother, male, or female stranger) were found to be discriminative for reliable changes in sex-typed play. Sex-typed play was found to vary as a function of the social stimulus situation and as a function of the type of play response required. All children played predominantly feminine while alone in the playroom. While no single environmental stimulus was consistently discriminative for masculine play across children, at least one stimulus condition was found for each subject under which he played predominantly masculine.

Intra-subject controlled time-out (social isolation) in the modification of self-injurious behaviour.

This study deals with the controlling of self-injurious behaviour in a profoundly retarded girl. The main therapeutic tool, social isolation, was carried out under normal ward conditions and was statistically evaluated in an intra-subject design without reversal conditions. The procedure reduced the self-injurious behaviour to a near-zero level.

Behavioral treatment of deviant sex-role behaviors in a male child.

This study demonstrated reinforcement control over pronounced feminine behaviors in a male child who had been psychologically evaluated as manifesting "childhood cross-gender identity". The clinical history of the subject paralleled the retrospective reports of adult transsexuals, including (a) cross-gender clothing preferences, (b) actual or imaginal use of cosmetic articles, (c) feminine behavior mannerisms, (d) aversion to masculine activities, coupled with preference for girl playmates and feminine activities, (e) preference for female role, (f) feminine voice inflection and predominantly feminine content in speech, and (g) verbal statements about the desire or preference to be a girl. The subject was treated sequentially in the clinic and home environments by his mother, trained to be his therapist. The mother was taught to reinforce masculine behaviors and to extinguish feminine behaviors, by using social reinforcement in the clinic and a token reinforcement procedure in the home. During this treatment, his feminine behaviors sharply decreased and masculine behavior increased. The treatment effects were found to be largely response-specific and stimulus-specific; consequently, it was necessary to strengthen more than one masculine behavior and weaken several feminine behaviors, in both clinic and home settings. A multiple-baseline intrasubject design was used to ensure both replication and identification of relevant treatment variables. Follow-up data three years after the treatment began suggests that the boy's sex-typed behaviors have become normalized. This study suggests a preliminary step toward correcting pathological sex-role development in boys, which may provide a basis for the primary prevention of adult transsexualism or similar adult sex-role deviation.

The behavioral treatment of a "transsexual" preadolescent boy.

Behavioral treatment procedures were developed to suppress feminine sex-typed behaviors and to increase masculine sex-typed behaviors in an 8-year-old boy with “childhood cross-gender identity.” The boy's clinical history paralleled the retrospective reports of adult transsexuals, including (1) feminine voice inflection and predominantly feminine content in speech, (2) verbal self-reference as “sissy” and “fag” and statements about his preference to be a girl, (3) feminine hand and arm gestures and “swishy” gait, (4) an aversion to masculine play activities, (5) a strong preference for girl playmates and taking a feminine role in play and role-playing, and (6) improvised cross-dressing. With a multiple-baseline intrasubject design across stimulus environments and across behaviors, the subject was treated sequentially in the clinic, at home, and in the school. The boy's mother was trained to administer a token economy program in the home, and the school teacher was taught to apply a response-cost procedure in the classroom. The initial treatment effects were found to be largely response specific and stimulus specific, necessitating treatment for a number of behaviors in the three major environments. Followup data 12 months after treatment termination suggest that the boy's sex-typed behaviors have become essentially normalized. This treatment holds promise for correcting pathological gender identity development in boys and for relieving the associated emotional adjustment problems.