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L Clark Johnson

Publications and source records attributed to L Clark Johnson.

18 recordsLinked to original sources
PubMed2006

Methodological issues associated with group intervention research.

Interventions using a group format can be powerful treatment modalities. However, a review of nursing journals most likely to report the conduct of group research by nurses showed that less than 1% of nursing research reports used this approach and that none accounted for group-level effects in the analysis. This article discusses methodological issues inherent in group intervention research. We begin by offering examples of variables that can be incorporated into group research. We then present some challenges that researchers must address in collecting data when group formats are used. We end with recommendations for conducting group intervention research and by addressing issues associated with interpreting and reporting results.

Analysis of Variance↗
PubMed2006

Functional magnetic resonance imaging in nursing research.

Functional magnetic resonance imaging (fMRI) is a powerful noninvasive neuroimaging technique nurse scientists can use to investigate the structure and cognitive capacities of the brain. A strong magnetic field and intermittent high-frequency pulses cause protons in body tissues to release energy, which can be recorded and processed into images that are sensitive to specific tissue characteristics. Although temporal and spatial resolution constraints define an upper limit to the precision of magnetic resonance (MR) scanners, the primary index of neuronal activity, hemodynamic response, can be efficiently estimated. Characteristics of the experimental environment, the hypothesis of interest, and the physiology of the cognitive process under investigation provide guidance for the design and limit available options. The processing of functional data to remove unwanted variability is briefly described as are the techniques used to estimate statistical effects and control for the rate of false positives in the results. A detailed applied example of nursing research is included to demonstrate the practical application of the theory, methods, and techniques being discussed. A glossary of key terms is also provided.

Adult↗
PubMed2005

Replicable functional magnetic resonance imaging evidence of correlated brain signals between physically and sensory isolated subjects.

OBJECTIVES: Previous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) experiments have suggested that correlated neural signals may be detected in the brains of individuals who are physically and sensorily isolated from each other. Functional MRI and EEG methods were used in the present study in an attempt to replicate these findings. DESIGN/SETTINGS: Subjects were electrically and magnetically shielded because of the characteristic surroundings of the scanner room. During the experiment, the nonstimulated subject was placed in the scanner with sensory isolating goggles covering the subject's eyes. The stimulated subject was placed 30 feet away and sat in front of a video monitor that presented an alternating schedule of six stimulus-on/stimulus-off conditions. The stimulus- on condition consisted of a flickering checkerboard pattern whereas the stimulus-off condition consisted of a static checkerboard. Stimulus-on/-off conditions were presented in the sequence on/off/on/off/on/off. The duration of these intervals was randomly assigned but consistently provided a total of 150 seconds of flicker and 150 seconds of static. Sessions were repeated twice to assess possible replication of the phenomenon. OUTCOME MEASURES: Changes in fMRI brain activation (relating to blood oxygenation) and EEG signals were measured in the nonstimulated subjects. Changes occurring during stimulus-on conditions were statistically compared to changes occurring during the stimulus-off conditions. RESULTS: Statistically significant changes in fMRI brain activation and EEG signals were observed when comparing the stimulus-on condition to the stimulus-off condition in nonstimulated subjects (p < 0.001, corrected for multiple comparisons). For fMRI, these changes were observed in visual brain areas 18 and 19 (Brodmann areas). One of the subjects replicated the results. CONCLUSIONS: These data replicate previous findings suggesting that correlated neural signals may be detected by fMRI and EEG in the brains of subjects who are physically and sensorily isolated from each other.

Adult↗
PubMed2004

Electroencephalographic evidence of correlated event-related signals between the brains of spatially and sensory isolated human subjects.

OBJECTIVE: To determine whether correlated event-related potentials (ERPs) can be detected between the brains of spatially and sensory isolated human subjects. DESIGN AND SETTING: Simultaneous digitized electroencephalograms (EEGs) were recorded from the occipital area in pairs of human subjects placed in sound attenuated rooms separated by 10 meters. One person relaxed in one of the rooms while the other received visual stimulation while in the other room. Prior to each experiment, members of the pair were randomly designated as sender and receiver. Sessions were subsequently repeated with subjects reversing their roles. Previous to each session, the sender was instructed "to attempt sending an image/thought." The receiver was instructed "to remain open to receive any image/thought from his/her partner." Alternating stimulus-on/stimulus-off conditions were presented throughout the session to the sender, while a stimulus-off condition was presented to the receiver. SUBJECTS: Thirty-seven (37) female, and 23 male subjects (n = 60; 30 pairs) participated in the study. Subjects knew each other well and claimed to have previous experience of being emotionally/psychologically connected to one another. OUTCOME MEASURES: A Runs test was applied to compare EEG "hits" in the receiver's EEG during the sender' stimulus-on condition versus sender's stimulus-off conditions. Test results at p < 0.01 were considered evidence of correlated brain signals. Pairs in whom at least one member had significant results were invited back for replication. RESULTS: Of the 60 subjects tested, 5 (4 women/1 man) showed significantly higher brain activation (p < 0.01) during their sending partner's stimulus-on condition as compared to stimulus-off condition. Using the Stouffer z meta-analytic method all receiver EEG results across all 60 subjects were combined by transforming the individual session p values into z scores. Data analyses showed overall significant results for EEG data recorded during the flickering condition (z =-3.28, p = 0.0005) as well as nonsignificant results for data recorded during the static condition (z = 0.35, p = 0.64). Four pairs participated in a replication experiment during which one pair replicated the effect. CONCLUSIONS: These results indicate that in some pairs of human subjects a signal may be detected in the brain of a distant member of the pair when the brain of the other member is visually stimulated. These data support the findings of similar studies performed in seven laboratories reported in the peer-reviewed literature since 1963. Research in this area should now proceed with investigation of its physical and biologic mechanism, its generalizability to varying populations and relationships, and its clinical application.

Adult↗
PubMed2004

First record: a methodological approach to counter sampling bias.

One goal of survey research is to optimize sampling procedures so that the collected data will produce accurate population estimates. In this context, sampling bias is a primary threat to a study's validity. If individuals who do not respond are a random sample of the population, then the estimates obtained from such a subsample are unbiased. However, as the percentage of nonrespondents increases, the assumption of unbiased estimation becomes increasingly tenuous. At this point an investigator has two choices: delete all subjects who have not provided data as part of the first data collection, or allow a respondent's point of entry to define his baseline measures for the study. No previous discussion of the latter option has been noted in the methods literature. Therefore the authors have termed this approach to baseline the "first record". Conditions under which the "first record" technique would be appropriate or inappropriate are discussed.

Bias↗
PubMed2003

The prevalence of PTSD following the violent death of a child and predictors of change 5 years later.

In this study, we examined the violent death bereavement trajectories of 173 parents by following them prospectively for 5 years after their children's deaths by accident, suicide, homicide, or undetermined causes. Using latent growth curve methodology, we examined how the initial level of PTSD and the rate of change over time were influenced by 9 predictors: the deceased children's causes of death, parents' gender, self-esteem, 3 coping strategies, perceived social support, concurrent levels of mental distress, and an intervention offered in early bereavement. Six of the nine factors predicted initial levels of PTSD; however, only parents' gender and perceived social support predicted change in PTSD over the 5-year time frame. Five years postdeath, 3 times as many study mothers (27.7%) met diagnostic criteria for PTSD and twice as many study fathers (12.5%) met diagnostic criteria for PTSD compared with the normative samples.

Adaptation, Psychological↗
PubMed2003

Bereaved parents' outcomes 4 to 60 months after their children's deaths by accident, suicide, or homicide: a comparative study demonstrating differences.

In this article, the authors revisit a controversial issue in the bereavement field: Does one violent cause of death of a child influence parents' outcomes more than another? To address this question, we observed 173 parents prospectively 4, 12, 24, and 60 months after their children's deaths by accident, suicide, or homicide. Quantitative and qualitative research methods were used to examine the influence of three types of a child's violent death and time since death upon 4 parent outcomes (mental distress, post-traumatic stress disorder [PTSD], acceptance of the child's death, and marital satisfaction). The results showed a significant interaction for the bereavement Group x Time effect for acceptance of death, a significant main effect for time for all four outcomes, and a significant main effect for group (homicide) for PTSD. Nearly 70% of the parents reported that it took either 3 or 4 years to put their children's death into perspective and continue with their own lives; however the child's cause of death did not significantly influence parents' sense of timing in this regard. Clinical and research implications of the findings are discussed.

Accidents↗
PubMed2003

Finding meaning in a child's violent death: a five-year prospective analysis of parents' personal narratives and empirical data.

Finding meaning in the death of a loved one is thought to be extremely traumatic when the circumstances surrounding the death is perceived to be due to negligence, is intentional, and when the deceased suffered extreme pain and bodily harm immediately prior to death. We addressed this assumption by obtaining personal narratives and empirical data from 138 parents 4, 12, 24, and 60 months after an adolescent's or young adult child's death by accident, suicide, or homicide. Using the Janoff-Bulman and Frantz's (1997) framework of meaning-as-comprehensibility and meaning-as-significance, the purposes were to identify the time course to find meaning, present parents' personal narratives describing finding meaning in their experiences, identify predictors of finding meaning, and compare parents who found meaning versus those who did not on five health and adjustment outcomes. The results showed that by 12 months post death, only 12% of the study sample had found meaning in a child's death. By 60 months post death, 57% of the parents had found meaning but 43% had not. Significant predictors of finding meaning 5 years post death were the use of religious coping and support group attendance. Parents who attended a bereavement support group were 4 times more likely to find meaning than parents who did not attend. Parents who found meaning in the deaths of their children reported significantly lower scores on mental distress, higher marital satisfaction, and better physical health than parents who were unable to find meaning. Recommendations for future research are made.

Adaptation, Psychological↗
PubMed2003

Challenging the myths about parents' adjustment after the sudden, violent death of a child.

PURPOSE: To examine three commonly held myths: (a) a child's death by suicide results in the worst parental outcomes compared with other causes of violent death, (b) divorce is not only more common among bereaved than nonbereaved married couples, it might be inevitable, and (c) "letting go and moving on" is an essential bereavement task needed for a satisfactory adjustment following the violent death of a child. DESIGN AND METHODS: Review of empirical evidence and critical reviews, review of Internet resources available to the general public, and the inclusion of original data obtained from a longitudinal, prospective study conducted by the authors. FINDINGS: Conclusive evidence was found to dispel two of the three myths, but sufficient evidence was not found to draw conclusions about the third myth regarding parents' adjustment to a child's suicidal death. CONCLUSIONS: Myths in regard to parental bereavement are resistant to disconfirming evidence and they appear to persist among professional practitioners and the general public despite contrary empirical evidence.

Accidents↗
PubMed2003

A process for consolidation of redundant nursing documentation forms.

Form redundancy can lead to duplicate documentation which can be the source of patient and staff frustration, as well as data errors. A data-driven systematic process for consolidation of the multiple redundant forms used in various patient care areas across a health care delivery system is proposed and tested using the 21 intake forms currently used by a regional HMO.

Documentation↗
PubMed2003

One size does not fit all: interpreting laboratory data in pediatric patients.

Results of laboratory tests for kidney stone risk factors are reported based on adult reference ranges and are not readily interpretable in children. We have developed a solution which converts laboratory output to appropriate pediatric patient-adjusted relative units, compares results using age-specific reference ranges, and flags out-of-range values. The example presented demonstrates how clinicians with technical skills can use existing computer resources to develop effective solutions to problems they experience in clinical practice.

Child↗
PubMed2003

Smaller and faster: using a handheld computer to support a bedside vascular access team.

An application for a handheld computer was developed to support the Vascular Access team in an academic medical center. The development involved workflow analysis and usability testing centered on the users. The application interfaced with the desktop to generate the documentation needed for the charts and to populate the database used to track productivity, volume, outcomes, etc. Post-implementation evaluations provided feedback to validate the utility of the system to support workflow of the team.

Catheterization, Central Venous↗
PubMed2002

Patterns of mental distress following the violent death of a child and predictors of change over time.

We observed 173 parents bereaved by the violent death of an adolescent or young adult child. Data were collected 4, 12, 24, and 60 months postdeath. Using latent growth modeling, we examined how initial levels of mental distress and the rate of change over time are influenced by nine predictors: parents' gender, self-esteem, three coping strategies, perceived social support, negative life stressors, posttraumatic stress disorder (PTSD) symptoms, and an intervention offered in the early bereavement period. The results support a multiple-risk and -protective factor model of loss accommodation. Parents' gender, self-esteem, and affective and repressive coping were predictive of changes in mental distress over time. Although parents' initial levels of PTSD were the best predictor of baseline mental distress, they did not predict reductions in distress 5 years later. Theoretical, empirical, and clinical implications are discussed.

Accidents↗
PubMed2002

Bereaved parents' use of individual, family, and community resources 4 to 60 months after a child's violent death.

We recruited a community-based sample of 261 parents bereaved by the violent deaths of their 12- to 28-year-old children. Parents were observed over time, and data were collected from several sources. The findings showed that of six individual, family, and community resources examined, none of the resources seemed to improve parents' outcomes either 1 or 5 years later. Implications of the findings are discussed.

Accidents↗
PubMedDate not supplied

Instrument development and evaluation of domestic preparedness training for first responders.

INTRODUCTION: In the wake of domestic terrorists attacks on 11 September 2001 and subsequent bioterrorist events employing anthrax, there no longer can be any debate about the potential for attacks employing Nuclear, Biological, or Chemical (NBC)/Weapons of Mass Destruction (WMD). As one way of acknowledging this long-standing threat and, in a concerted effort to mitigate the effects of possible future domestic NBC/WMD terrorist attacks, the US Department of Defense (DOD) and other US governmental agencies already had mounted an effort to provide Domestic Preparedness Training for First Responders in urban centers throughout the USA. METHODS: A paper and pencil questionnaire specifically designed to evaluate the effectiveness of Domestic Preparedness Training for Emergency First Responders has been developed. An earlier version of this instrument was piloted with a convenience sample of firefighters and paramedics (n = 78) in a northwest state. Based on replies to the pilot questionnaire, a pool of 27 items based on the objectives and content of the NBC/WMD Domestic Preparedness Awareness and Operations courses (plus additional background and appraised competency items) were selected for inclusion in a Domestic Preparedness Questionnaire (DPQ). RESULTS: This paper first describes the essential psychometric properties of the DPQ based on replies from baseline and follow-up samples (n = 206 and n = 246 respectively) of urban firefighters and paramedics employed by a metropolitan city in a northwest state. The DPQ was employed to evaluate the outcomes of Domestic Preparedness training provided to a sample of urban fire-service personnel. The DPQ documented significant improvements in a group of "DP trained"-urban firefighters (n = 80) both in their awareness and operations content knowledge as well as in their perceived competencies to respond to acts of biological, chemical, or nuclear terrorism "in their own community" at four months post-training. A comparison group of "Not DP-trained" firefighters (n = 78) showed no statistically significant changes on these DPQ indices, suggesting that the documented improvements in the "DP-trained" firefighters on the DPQ were not due to "test reactivity" or to "historical" factors. CONCLUSION: The findings suggest that the DPQ has adequate inter-item and test-retest reliability, possesses concurrent validity, and appears to be a sensitive measure of the Domestic Preparedness Training provided for urban firefighter and paramedic First Responders.

Bioterrorism↗
PubMedDate not supplied

Suicide ideation among parents bereaved by the violent deaths of their children.

Suicidal behaviors of parents bereaved by a child's suicide have received considerable attention by researchers, but deaths by other violent causes have not. We observed 175 bereaved parents for five years following three types of violent death: accidents, homicides, and suicides. The results showed that the incidence of suicidal ideation (SI) among the study parents was 13% (n = 34) over the 5 years and 9% (n = 24) at the initial data collection four months after the death of an adolescent or young adult child. Comparisons of study parents grouped by the presence or absence of SI showed that after corrections were made for the number of t-tests conducted, statistically significant differences on three of four outcome variables remained (mental distress, depression, and posttraumatic stress disorder [PTSD], but not on acceptance of the child's death). The groups also differed significantly on four of seven mediating variables examined. The hypothesis that parents whose children died by suicide would report the highest incidence of suicidal ideation was not supported. Regression analyses showed that SI was a significant predictor of depression one year, but not five years, after the violent death of a child. The hypothesis that SI would predict both depression and PTSD one year postdeath was not supported. Clinical and policy recommendations are offered.

Accidents↗
PubMedDate not supplied

A process for consolidation of redundant documentation forms.

Forms capturing redundant data can lead to duplicate documentation. This can be a source of patient and staff frustration, as well as data errors. The definition of a process aimed at examining the data captured on forms documenting similar aspects of patient care is necessary to avoid this problem of duplicate documentation. A data-driven systematic process for consolidation of the multiple redundant forms used in various patient care areas across a healthcare delivery system is proposed and tested using the 21 intake forms currently used by a regional Health Maintenance Organization (HMO). The analytic and subsequent reporting processes used in this project provide a systematic method of forms consolidation that can be applied to other settings.

Abstracting and Indexing↗