Analysis of clustered data in community psychology: With an example from a worksite smoking cessation project

Although it is common in community psychology research to have data at both the community, or cluster, and individual level, the analysis of such clustered data often presents difficulties for many researchers. Since the individuals within the cluster cannot be assumed to be independent, the use of many traditional statistical techniques that assumes independence of observations is problematic. Further, there is often interest in assessing the degree of dependence in the data resulting from the clustering of individuals within communities. In this paper, a random-effects regression model is described for analysis of clustered data. Unlike ordinary regression analysis of clustered data, random-effects regression models do not assume that each observation is independent, but do assume data within clusters are dependent to some degree. The degree of this dependency is estimated along with estimates of the usual model parameters, thus adjusting these effects for the dependency resulting from the clustering of the data. Models are described for both continuous and dichotomous outcome variables, and available statistical software for these models is discussed. An analysis of a data set where individuals are clustered within firms is used to illustrate fetatures of random-effects regression analysis, relative to both individual-level analysis which ignores the clustering of the data, and cluster-level analysis which aggregates the individual data. Preparation of this article was supported by National Heart, Lung, and Blood Institute Grant R18 HL42987-01A1, National Institutes of Mental Health Grant MH44826-01A2, and University of Illinois at Chicago Prevention Research Center Developmental Project CDC Grant R48/CCR505025.     

关于麻醉后监测治疗室的伦理思考

麻醉后监测治疗室(post-anesthesia care unit,PACU)中医学高新技术设备对确保手术后患者的安全发挥极其重大的作用,然而PACU中也产生许多危机与伦理冲突。为了PACU的良性发展,我们认为如下伦理准则必须遵循:科学认定准则、最佳选择准则、精益求精准则、无伤准则、患者自主准则。     

The Great Mother and the Terrible Mother: mimesis,alterity and attachment in adolescence

This paper discusses attachment, the longing for familiarity and sameness (mimesis), the search for difference and separateness (alterity) and the problem with the Other¹ seen through the lens ofthe individuation process in adolescence. These are explored with reference to relational aspects and Levinas and Girard's divergent views of the Other. The relational space, which in Phillip Bromberg's (2003) words is ‘uniquely relational, but still uniquely individual’ and in which analyst and patient ‘stand together in the space between realities’, might under exceptional circumstances be transformed into ‘a twilight space where the impossible becomes possible’ (p. 573). I will sketch a developmental trajectory starting from primitive states, in which the presence of the Other,as a separate entity cannot be tolerated and where the patient strives for total mimesis. Should the analyst prematurely shatter this illusion, she becomes an alien ‘Other’; a wolf in sheep's clothing. I trace the current psychoanalytic paradigm shift to an emphasis on the co‐creation of meaning in the interpersonal space and explore what alterity consists of and how much of the other's unknowability can be tolerated and respected without a translation into one's own idiom. The clinical vignettes illustrate aspects of therapy which normally lie outside the analytical remit and are culled from an inpatient setting and private practice.     

The segment as the minimal planning unit in speech production: Evidence based on absolute response latencies

A minimal amount of information about a word must be phonologically and phonetically encoded before a person can begin to utter that word. Most researchers assume that the minimum is the complete word or possibly the initial syllable. However, there is some evidence that the initial segment is sufficient based on longer durations when the initial segment is primed. In two experiments in which the initial segment of a monosyllabic word is primed or not primed, we present additional evidence based on very short absolute response times determined on the basis of acoustic and articulatory onset relative to presentation of the complete target. We argue that the previous failures to find very short absolute response times when the initial segment is primed are due in part to the exclusive use of acoustic onset as a measure of response latency, the exclusion of responses with very short acoustic latencies, the manner of articulation of the initial segment (i.e., plosive vs. nonplosive), and individual differences. Theoretical implications of the segment as the minimal planning unit are considered.     

Labor supply and consumption of food in a closed economy under a range of fixed- and random-ratio schedules: tests of unit price

The behavioral economic concept of unit price predicts that consumption and response output (labor supply) are determined by the unit price at which a good is available regardless of the value of the cost and benefit components of the unit price ratio. Experiment 1 assessed 4 pigeons' consumption and response output at a range of unit prices. In one condition, food was available according to a range of fixed-ratio schedules, whereas in the other condition, food was available according to a range of random-ratio schedules. Consistent with unit price predictions, consumption and response output were approximately equivalent across schedule types within the lower range of unit prices. However, at Unit Prices 64 (ratio value = 192) and greater, considerably more consumption and response output were observed in the random-ratio condition. Experiment 2 replicated these findings with 4 pigeons using the rapid demand curve assay procedure that is commonly used in the behavioral economics literature. Findings are integrated with two mathematical models of behavior under variable reinforcer delays.     

Second-order schedules of token reinforcement with pigeons: implications for unit price

Four pigeons were exposed to second-order schedules of token reinforcement, with stimulus lights serving as token reinforcers. Tokens were earned according to a fixed-ratio (token-production) schedule, with the opportunity to exchange tokens for food (exchange period) occurring after a fixed number had been produced (exchange-production ratio). The token-production and exchange-production ratios were manipulated systematically across conditions. Response rates varied inversely with the token-production ratio at each exchange-production ratio. Response rates also varied inversely with the exchange-production ratio at each token-production ratio, particularly at the higher token-production ratios. At higher token-production and exchange-production ratios, response rates increased in token-production segments closer to exchange periods and food. Some conditions were conducted in a closed economy, in which the pigeons earned all their daily ration of food within the session. Relative to comparable open-economy conditions, response rates in the closed economy were less affected by changes in token-production ratio, resulting in higher levels of food intake and body weight. Some of the results are consistent with the economic concept of unit price, a cost-benefit ratio comprised of responses per unit of food delivery, but most are well accounted for by a consideration of the number of responses required to produce exchange periods, without regard to the amount of reinforcement available during those exchange periods.     

Sensory sensitivity after acquired brain injury: A systematic review

Patients with acquired brain injury frequently report experiencing sensory stimuli as abnormally under- (sensory hyposensitivity) or overwhelming (sensory hypersensitivity). Although they can negatively impact daily functioning, these symptoms are poorly understood. To provide an overview of the current evidence on atypical sensory sensitivity after acquired brain injury, we conducted a systematic literature review. The primary aim of the review was to investigate the behavioural and neural mechanisms that are associated with self-reported sensory sensitivity. Studies were included when they studied sensory sensitivity in acquired brain injury populations, and excluded when they were not written in English, consisted of non-empirical research, did not study human subjects, studied pain, related sensory sensitivity to peripheral injury or studied patients with a neurodegenerative disorder, meningitis, encephalitis or a brain tumour. The Web of Science, PubMed and Scopus databases were searched for appropriate studies. A qualitative synthesis of the results of the 81 studies that were included suggests that abnormal sensory thresholds and a reduced information processing speed are candidate behavioural mechanisms of atypical subjective sensory sensitivity after acquired brain injury. Furthermore, there was evidence for an association between subjective sensory sensitivity and structural grey or white matter abnormalities, and to functional abnormalities in sensory cortices. However, further research is needed to explore the causation of atypical sensory sensitivity. In addition, there is a need for the development of adequate diagnostic tools. This can significantly advance the quantity and quality of research on the prevalence, aetiology, prognosis and treatment of these symptoms.     

THE EFFECTS OF INTERSPERSED MAINTENANCE TASKS ON ACADEMIC PERFORMANCE IN A SEVERE CHILDHOOD STROKE VICTIM

We examined the effects of task-sequencing variables on the academic performance of an 8-year-old severe stroke victim. Within a multiple baseline design, previously acquired (maintenance) task trials were systematically interspersed at designated points in treatment among new (acquisition) task trials. The results showed improvements in both academic responding and subjective ratings of motivation in each of four treated areas (spelling, reading, word-finding, and memory). Social validation data obtained from standardized school placement examinations suggested marked improvement in a variety of related areas of academic functioning. Results suggest that children suffering severe strokes may be capable of learning more than has previously been suspected, and that behavioral treatments may improve such children's functioning.     

You never know where you are going until you know where you have been: Disorganized search after stroke

Disorders in spatial exploration can be expressed in a disorganized fashion of target cancellation. There is debate regarding whether disorganized search is related to stroke in general, to right brain damage or to unilateral spatial neglect (USN) in particular. In this study, 280 stroke patients and 37 healthy control subjects performed a computerized shape cancellation test. We investigated the number of perseverations and several outcome measures regarding disorganized search: Consistency of search direction (best r), distance between consecutive cancelled targets and intersections with paths between previous cancelled targets. We compared performance between patients with left and right brain damage (L, R) and with and without USN (USN+, USN?), resulting in four subgroups: LUSN?, RUSN?, LUSN+, and RUSN+. Higher numbers of intersections were found for the left brain‐ and right brain‐damaged patients with USN and for the right brain‐damaged patients without USN, compared to healthy control subjects. Furthermore, right brain‐damaged patients with USN showed a higher number of intersections compared to right brain‐damaged patients without USN and compared to left brain‐damaged patients with USN. To conclude, disorganized search was most strongly related to the neglect syndrome, and patients with more severe USN were even more impaired.     

The Hong Kong version of the Oxford Cognitive Screen (HK-OCS): validation study for Cantonese-speaking chronic stroke survivors

This study reports the validation of the Hong Kong version of Oxford Cognitive Screen (HK-OCS). Seventy Cantonese-speaking healthy individuals participated to establish normative data and 46 chronic stroke survivors were assessed using the HK-OCS, Albert’s Test of Visual Neglect, short test of gestural production, and Hong Kong version of the following assessments: Western Aphasia Battery, MMSE, MoCA, Modified Barthel Index, and Lawton Instrumental Activities of Daily Living scale. The validity of the HK-OCS was appraised by the difference between the two participant groups. Neurologically unimpaired individuals performed significantly better than stroke survivors on the HK-OCS. Positive and significant correlations found between cognitive subtests in the HK-OCS and related assessments indicated good concurrent validity. Excellent intra-rater and inter-rater reliabilities, fair test–retest reliability, and acceptable internal consistency suggested that the HK-OCS had good reliability. Specific HK-OCS subtests including semantics, episodic memory, number writing, and orientation were the best predictors of functional outcomes.