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D W King

Publications and source records attributed to D W King.

At least 37 records · Page 2Linked to original sources
PubMed2000

A quantifiable alternative to double data entry.

Recent articles in this journal have questioned the effectiveness of double data entry to enhance the quality of clinical trials data entered into the computer from case report forms. Although double data entry is widely used, no definitive agreement has been reached as to how to model and quantify the time/cost involved to perform double data entry and the exact gain in data quality derived from its use. In this paper, an alternative to the verification step of double data entry is described. This alternative procedure involves the verification of a sample of records from the data set created from the single entry of the data into the computer. The sampling procedure used for this alternative procedure is known in the statistical quality control literature as a continuous sampling plan. This type of secondary check of the data has the following advantages: (1) it is easily performed by data entry personnel, (2) the cost/time necessary to perform the check along with the gain in quality of the data set can be computed, and (3) the sampling plan can be constructed to attain data quality goals set by the data management staff. Examples of how to select the parameters for this type of data quality assurance procedure are given in the paper.

Clinical Trials as Topic↗
PubMed2000

Posttraumatic stress disorder and retrospectively reported stressor exposure: a longitudinal prediction model.

There has been recent concern about the degree to which posttraumatic stress disorder (PTSD) symptomatology influences reports of prior exposure to highly stressful life events. In this longitudinal study of 2,942 male and female Gulf War veterans, the authors documented change in stressor reporting across 2 occasions and the association between change and PTSD symptom severity. A regression-based cross-lagged analysis was used to examine the relationship between PTSD symptom severity and later reported stressor exposure. Shifts in reporting over time were modestly associated with PTSD symptom severity. The cross-lagged analysis revealed a marginal association between Time 1 PTSD symptom severity and Time 2 reported stressor exposure for men and suggested that later reports of stressor exposure are primarily accounted for by earlier reports and less so by earlier PTSD symptomatology.

Adult↗
PubMed2000

Prognostic implication of contralateral secondary electrographic seizures in temporal lobe epilepsy.

PURPOSE: Interhemispheric propagation of seizures in temporal lobe epilepsy is frequently noted during intracranial EEG monitoring. We hypothesized that a distinct secondary electrographic seizure (DSES) in the temporal lobe contralateral to primary seizure onset may be an unfavorable prognostic indicator. METHODS: We reviewed intracranial depth electrode EEG recordings, 1-year outcome, and medical records of 51 patients (M 29, F 22: age 15-64 years) who underwent anterior temporal lobectomy during 1988-96. We defined DSES as a seizure that spread to the contralateral temporal lobe and produced distinct contralateral EEG features. The distinct feature was focal involvement of one or two electrode contacts at onset, which starts and evolves independently from the ipsilateral temporal lobe. We considered DSES as the predominant seizure pattern when it occurred in more than one half of the patients' recorded seizures. RESULTS: Only nine of 19 (47%) patients with predominant DSES had a 1-year seizure-free outcome, whereas 27 of 32 (84%) patients without predominant DSES had a 1-year seizure-free outcome (p < 0.01). Bitemporal independent seizures were more common in patients with predominant DSES (9/19 versus 0/32; p < 0.001). CONCLUSION: Our results suggest that distinct contralateral secondary electrographic seizure is a predictor of unfavorable outcome and is also more likely to be associated with bitemporal seizures.

Adolescent↗
PubMed2000

Proton magnetic resonance spectroscopic observations of epilepsia partialis continua in children.

We performed magnetic resonance spectroscopy in three pediatric patients (two boys and one girl, ages 11 to 17 years) with epilepsia partialis continua. Single-voxel proton magnetic resonance spectroscopy was performed on each patient. Data were acquired from voxels of 4 or 8 cm3 from the affected hemisphere and from contralateral homologous regions. The spectral peaks of several metabolites (N-acetyl-aspartate, choline, creatine, and lactate) were measured. Neuropathologic findings revealed Rasmussen's syndrome in two children and gliosis in one. We observed increased lactate-to-creatine ratios and reduced N-acetyl-aspartate-to-creatine ratios in the affected hemispheres in all three children with epilepsia partialis continua. These data support previous reports. The largest increase in the lactate-to-creatine ratio was detected in a patient with Rasmussen's syndrome and ongoing epilepsia partialis continua at the time of measurement. The other two patients had an increase in the lactate-to-creatine ratio and a decrease in the N-acetyl-aspartate-to-creatine ratio in the affected area. The increased lactate-to-creatine ratio was associated with recurrent focal seizures from different underlying pathologies.

Adolescent↗
PubMed2000

Gamma knife radiosurgery as a primary treatment for prolactinomas.

OBJECT: The purpose of this study was to estimate the efficacy of gamma knife radiosurgery (GKS) in controlling tumor growth and endocrinopathy associated with prolactinomas. METHODS: Between 1993 and 1997, 164 of 469 patients with pituitary adenomas treated by GKS harbored prolactinomas. The dose to the tumor margin ranged from 9 to 35 Gy (mean 31.2 Gy), and the visual pathways were exposed to a dose of less than 10 Gy. The mean tumor diameter was 13.4 mm. The mean follow-up time for 128 cases was 33.2 months (range 6-72 months). Tumor control was observed in all but two patients who underwent surgery 18 and 36 months, respectively, after GKS. Clinical cure was achieved in 67 cases. Clinical improvement was noted with a decrease in the hyperprolactinemia after GKS. Nonetheless, in 31 (29%) of 108 patients who were followed for more than 2 years no improvement in serum prolactin levels was demonstrated, although this could be normalized by bromocriptine administration after treatment. Nine infertile women became pregnant 2 to 13 months after GKS and all gave birth to normal children. There was no visual deterioration related to GKS. Five women experienced premature menopause. In these patients there was subtotal disappearance of the tumor and an empty sella developed. CONCLUSIONS: Gamma knife radiosurgery as a primary treatment for prolactinomas can be safe and effective both for controlling tumor growth and for normalization of prolactin hypersecretion. A higher margin dose (> or = 30 Gy) seemed to be associated with a better clinical outcome. Gamma knife radiosurgery may make prolactinomas more sensitive to the bromocriptine.

Humans↗
PubMed2000

Coping with Gulf War combat stress: mediating and moderating effects.

The authors examined relationships between method of coping with combat-related stress and psychological symptoms among Gulf War Army personnel (N = 1,058). Participants were surveyed on return from the Gulf region (Time 1) with the Coping Responses Inventory (R. Moos, 1990) and a measure of combat exposure. Outcomes were symptom measures of posttraumatic stress disorder (PTSD) and depression. At Time 2 (18-24 months) participants completed the same symptom measures and an index of postwar stress. Higher proportions of approach-based coping in the war zone were related to lower levels of psychological symptoms. Combat exposure moderated the effects of coping on Time 1 PTSD. Coping predicted changes in symptoms of depression but not PTSD. Combat exposure affected changes in depression through postwar stress but had a direct negative effect on PTSD.

Adaptation, Psychological↗
PubMed2000

An advanced toothbrush with improved plaque removal efficacy.

PURPOSE: To compare the plaque removal efficacy and safety of a new advanced manual toothbrush, the Oral-B CrossAction, with seven other toothbrushes. MATERIALS AND METHODS: Seven independent, cross-over design clinical studies were conducted using the same examiner who was blind to the identity of the test products and treatment assignments. In each study, approximately 75 healthy adult subjects from a general population brushed with their randomly assigned toothbrush (CrossAction or comparison brush) at Visit 1 for 1 min without supervision or instruction in brushing technique. Subjects returned after a 1-week washout period and brushed with the alternate toothbrush (Visit 2). Plaque was evaluated before and after brushing using the Rustogi Modified Navy Plaque Index. Statistical analyses were conducted by an independent statistician who remained blind to the identity of all test products. RESULTS: Each of the toothbrushes tested provided significant (P < or = 0.0001) reductions in plaque scores after a single brushing. In each of the studies, the CrossAction toothbrush removed significantly (P < or = 0.0001) greater amounts of whole mouth, gingival margin, and approximal plaque than the compared toothbrush. All toothbrushes were found to be safe, with no changes in oral tissues or restorations observed over the course of each study. The results from these studies were consistent, demonstrating that the CrossAction toothbrush significantly enhances the ability of subjects to remove more plaque during normal brushing compared to seven other toothbrushes.

Adult↗
PubMed2000

A 3-month comparative investigation of the safety and efficacy of a new toothbrush: results from two independent clinical studies.

PURPOSE: To compare the efficacy of a new toothbrush featuring a novel brush head design with those of two established toothbrushes by measuring plaque and gingivitis over a period of 12 weeks. MATERIALS AND METHODS: The Oral-B CrossAction toothbrush was compared with the Dr. Best InterDent and Crest DeepSweep toothbrushes in two independent, parallel-group, examiner-blind clinical studies. Each study involved approximately 100 healthy individuals from a general population. At baseline, after 23-25 hrs of no oral hygiene, oral hard and soft tissues were examined and whole mouth, marginal and approximal plaque scores and whole mouth gingivitis scores were recorded. Subjects in the two studies were asked to use their assigned toothbrush twice a day. No instruction in brushing technique or brushing time was given. After a period of 6 weeks and finally after 12 weeks, subjects in the studies were reassessed for oral tissue status, and their plaque and gingival indices were rescored. RESULTS: In each of the two studies, the tested toothbrushes significantly reduced levels of plaque and gingivitis. The CrossAction toothbrush was, however, more effective in reducing both plaque and gingivitis over 12 weeks, the differences in favor of the CrossAction being statistically significant. All the toothbrushes tested in this investigation were found to be safe with no evidence of hard or soft tissue trauma.

Adolescent↗
PubMed1999

Randomized trial of preoperative cimetidine in patients with colorectal carcinoma with quantitative assessment of tumor-associated lymphocytes.

BACKGROUND: Previous studies have suggested that cimetidine, a histamine-2 receptor antagonist with immunostimulatory effects, may improve survival in patients with colorectal carcinoma. This effect may be apparent by an increase in the number of peritumoral lymphocytes. A prospective, double blind, randomized, placebo-controlled trial of a short course of preoperative treatment with cimetidine in patients with colorectal carcinoma was performed to assess the effect of cimetidine on survival and on the number of peritumoral lymphocytes. METHODS: One hundred and twenty-five patients who were scheduled to undergo elective colon or rectal excision for carcinoma were randomized to receive either placebo or cimetidine preoperatively for 5 days. In addition to standard histopathology, immunohistochemistry and computer video image analysis were used to assess the number of peritumoral lymphocytes in an objective manner. Interim survival analysis according to the Kaplan-Meier method was performed. RESULTS: A trend toward a survival advantage in the group of patients receiving cimetidine (800 mg twice daily) compared with the placebo group was observed (P = 0.20, log rank test) that was most marked in patients with replication error negative tumors (P = 0.04). Similarly, in these two groups there was a trend toward an increase in the number of patients with a conspicuous lymphocytic infiltration (P = 0.10, chi-square test). However, there was no difference in the number of peritumoral lymphocytes as measured by image analysis. CONCLUSIONS: Based on the results of the current study, a short course of preoperative treatment with cimetidine does appear to have an effect on patient survival; however, the exact mechanism is unknown. The failure of this study to demonstrate a clear increase in the local lymphocyte response does not exclude an immunologic mechanism of action.

Adjuvants, Immunologic↗
PubMed1999

Partners' ratings of combat veterans' PTSD symptomatology.

The current study examined the concordance of combat veterans' scores on the Mississippi Scale for Combat-Related PTSD, with scores on a parallel version of that instrument completed by partners to assess veterans' symptoms. Further, the study examined the impact of quality of the marital relationship on score concordance. Bivariate and multiple regression were used with a sample of 466 veteran-partner dyads obtained from the National Vietnam Veterans Readjustment Study. There was moderate agreement in symptom reporting between veterans and their partners and little evidence to suggest that the quality of the relationship impacted upon the association between partner and veteran scores.

Combat Disorders↗
PubMed1999

Modeling physical health and functional health status: the role of combat exposure, posttraumatic stress disorder, and personal resource attributes.

This study examined associations of combat exposure and posttraumatic stress disorder (PTSD) with physical health conditions and also incorporated hardiness and social support as mediators and functional health status as an outcome. Data were derived from 1,632 male and female Vietnam veterans who participated in the National Vietnam Veterans Readjustment Study. Path analysis revealed that hardiness and social support operated primarily as intermediary variables between combat exposure and PTSD, and PTSD emerged as the pivotal variable explaining physical health conditions and functional health status. Gender-based differences in means and patterns of associations among variables were found. The results stress the importance of assessing trauma in clinical settings as a meaningful determinant of health outcomes.

Adult↗
PubMed1999

The utilization of colon transit scintigraphy in the diagnostic algorithm for patients with chronic constipation.

We performed a retrospective utilization study covering a four-year period to determine how physicians familiar with colon transit scintigraphy (CTS) use it to manage patients with chronic constipation. Following CTS, there was a change is both frequency and likelihood of diagnosis. The diagnosis was changed in 51% of patients-37% of those considered to have slow transit constipation (STC) before CTS, 43% with obstructed defecation, and 64% with functional bowel disease (FBD). CTS increased the diagnostic likelihood in all groups. Of patients with the diagnosis of STC, 16% were considered "almost certain" before CTS while 83% were considered "almost certain" after CTS. For FBD comparable percentages were 13% and 62%. CTS may play a major role in the diagnostic work-up of patients with chronic constipation, both altering diagnosis and increasing diagnostic certainty.

Adolescent↗
PubMed1999

Posttraumatic stress disorder in a national sample of female and male Vietnam veterans: risk factors, war-zone stressors, and resilience-recovery variables.

Relationships among pretrauma risk factors (e.g., family instability, childhood antisocial behavior), war-zone stressors (e.g., combat, perceived threat), posttrauma resilience-recovery variables (e.g., hardiness, social support), and posttraumatic stress disorder (PTSD) symptom severity were examined. Data from a national sample of 432 female and 1,200 male veterans were analyzed using structural equation modeling. For both genders, direct links to PTSD from pretrauma, war-zone, and posttrauma variable categories were found; several direct associations between pretrauma and posttrauma variables were documented. Although war-zone stressors appeared preeminent for PTSD in men, posttrauma resilience-recovery variables were more salient for women. Researchers, policymakers, and clinicians are urged to take a broad view on trauma and its sequelae, especially regarding possible multiple exposures over time and the depletion and availability of important resources.

Adult↗
PubMed1999

Course and predictors of posttraumatic stress disorder among Gulf War veterans: a prospective analysis.

Rates and predictors of posttraumatic stress disorder (PTSD) over time are not well understood. This study is the first to look at the rates of PTSD immediately following war and 2 years later using a large cohort (N = 2,949) of Gulf War veterans. Using a cut score to indicate presumptive PTSD, 3% of participants exceeded the cutoff at Time 1 compared with 8% at Time 2. Those who exceeded the cutpoint at Time 1 were up to 20 times more likely to exceed the cutpoint at Time 2 than those who did not exceed the cutpoint at Time 1. Women and those with high levels of combat exposure were at increased risk for PTSD at both times. Being young, being single, and having previous combat experience were associated with increased risk at Time 1 only, whereas reservists and enlisted personnel were at increased risk at Time 2 only. These findings indicate that, although low initially, rates of PTSD increased substantially over time.

Adult↗
PubMed1999

Peritonectomy and intraperitoneal chemotherapy in appendiceal and colorectal cancer.

BACKGROUND: Peritoneal spread of gastrointestinal malignancies has been regarded as an incurable disease, and treatment has been aimed at short-term palliation. The use of cytoreductive surgery, including peritonectomy procedures and intraperitoneal chemotherapy, has been proposed with the intention of prolonging survival, and perhaps curing patients with peritoneal carcinomatosis from appendiceal and possibly colon cancers. A series of eight patients who have undergone this procedure at St George Hospital is presented, and the results obtained by other groups are reviewed. METHOD: Eight patients fitted the criteria for peritoneal carcinomatosis between January 1996 and November 1998. In seven patients this was secondary to appendiceal or colon cancer. and one patient had signet ring cancer of the uterus. The surgical treatment involved removing all macroscopic evidence of disease, and this was followed by early postoperative intraperitoneal chemotherapy. RESULTS: The eight patients (seven female, one male) ranged in age from 25 to 67 years. There were seven complications, including two patients with pelvic abscesses, and one patient who developed Tenchkoff catheter occlusion. There were three deaths, one due to pelvic sepsis after 30 days, and the other two were due to metastatic disease. Of the remaining five patients, two have developed recurrence and three remain disease-free. CONCLUSION: The results of peritonectomy and intraperitoneal chemotherapy for appendiceal tumours are encouraging. The role in colorectal cancer is less clear, although there are some reports that suggest a benefit.

Abscess↗
PubMed1999

A comparison of magnetoencephalography, MRI, and V-EEG in patients evaluated for epilepsy surgery.

PURPOSE: To determine the efficacy and relative contribution of several diagnostic methods [ictal and interictal scalp and intracranial EEG, magnetic resonance imaging (MRI), and magnetoencephalography (MEG)] in identifying the epileptogenic zone for resection. METHODS: This was a prospective study using a masked comparison-to-criterion standard. Fifty-eight consecutive patients with refractory partial epilepsy from two university comprehensive epilepsy programs were studied. Patients who were evaluated for and underwent epilepsy surgery were recruited. The main outcome measure was the efficacy of each diagnostic method to identify the resected epileptogenic zone, when referenced to surgical outcome. RESULTS: MEG (52%) was second only to ictal intracranial V-EEG in predicting the epileptogenic zone for the entire group of patients who had an excellent surgical outcome (seizure free or rare seizure). In a subanalysis, for patients who had temporal lobe surgery, this same relation was seen (MEG, 57%, ictal intracranial V-EEG, 62%). With extratemporal resection, ictal (81%) and interictal (75%) intracranial EEG were superior to MEG (44%) in predicting the surgery site in those patients with an excellent outcome. Finally, for all patients who had a good surgical outcome, MEG (52%) was better than ictal (33%) or interictal (45%) scalp VEEG in predicting the site of surgery. CONCLUSIONS: These results indicate that MEG is a very promising diagnostic method and raise the possibility that it may obviate the need for invasive EEG in some cases or reduce the length of scalp EEG evaluation in others.

Adolescent↗
PubMed1999

Differential cognitive effects of carbamazepine and gabapentin.

PURPOSE: The cognitive effects of the newer antiepileptic drugs (AEDs) compared with the older standard AEDs are uncertain. METHODS: We directly compared the cognitive effects of carbamazepine (CBZ) and gabapentin (GBP) in 35 healthy subjects by using a double-blind, randomized crossover design with two 5-week treatment periods. During each treatment condition, subjects received either GBP, 2,400 mg/day, or CBZ (mean, 731 mg/day) adjusted to a dose to achieve midrange standard therapeutic blood levels (mean, 8.3 microg/ml). Subjects were tested at the end of each AED treatment period and in four drug-free conditions [two pretreatment baselines and two post-treatment washout periods (1 month after each AED)]. The neuropsychological test battery included 17 measures yielding 31 total variables. RESULTS: Direct comparison of the two AEDs revealed significantly better performance on eight variables for GBP, but none for CBZ. Comparison of CBZ and GBP to the nondrug average revealed significant statistical differences for 15 (48%) of 31 the variables. Pairwise follow-up analyses of the 15 variables revealed significantly better performance for nondrug average on 13 variables compared with CBZ, and on four compared with GBP. GBP was better than nondrug average on one variable. CONCLUSIONS: Although both CBZ and GBP produced some effects, GBP produced significantly fewer untoward cognitive effects compared with CBZ at the dosages used in this study.

Acetates↗