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C Black

Publications and source records attributed to C Black.

At least 91 records · Page 5Linked to original sources
PubMed1997

International applicability of the VF-14. An index of visual function in patients with cataracts.

PURPOSE: There is increased recognition that a rigorous approach to functional assessment should complement the assessment of clinical status. The authors compare the reliability, validity, and responsiveness to clinical change of a visual function index (VF-14) in non-U.S. and in U.S. patients with cataracts. DESIGN: An observational longitudinal study was performed. PARTICIPANTS: One thousand four hundred seven first eye cataract surgery patients were recruited in four international sites: Manitoba (Canada), Denmark, Barcelona (Spain), and the United States. INTERVENTION: Patients were evaluated before cataract surgery and at a 4-month postoperative follow-up visit. Patients completed the preoperative interview and the clinical examination (766 in the United States, 152 in Manitoba, 291 in Denmark, and 198 in Barcelona), and 91.3% of those (1284) also completed the 4-month postoperative follow-up interview and were evaluated postoperatively by an ophthalmologist. MAIN OUTCOME MEASURES: The authors used the following measures: the visual function index (VF-14), the Sickness Impact Profile (SIP), global measures of patients' trouble and satisfaction with vision, and best-corrected visual acuity (VA) in each eye. RESULTS: The VF-14 showed a high internal consistency reliability level in all sites (Cronbach's alpha coefficients > or = 0.84). Correlation of preoperative visual function index scores with the Vision-Related SIP was strong (r = -0.68 in non-U.S. and r = -0.57 in U.S. patients) and with VA in the eye with better vision was moderate (r = 0.40 and r = 0.27, respectively), the pattern of relationships being very similar among U.S. and non-U.S. patients. In patients with only first-eye surgery who reported that their initial trouble with vision had improved, the amount of change in visual function as assessed by the VF-14 (effect size) was large (1.01 for the non-U.S. patients and 1.17 for the U.S. patients). CONCLUSIONS: The non-U.S. versions of the visual function index (VF-14) analyzed are as reliable, valid, and responsive to clinical change as the original U.S. version. These versions are appropriate for international studies of cataract patients outcomes and possibly in routine clinical practice.

Aged↗
PubMed1997

Patients' acceptance of waiting for cataract surgery: what makes a wait too long?

The patient's perspective about waiting for elective surgery is an important consideration in the management of waiting lists, yet it has received little attention to date. This study was undertaken to assess the acceptability of personal waiting times from the perspective of patients, and to examine waiting time and patient characteristics associated with the perception that a wait for cataract surgery is too long. The international prospective study was conducted in three sites with explicit waiting systems: Manitoba, Canada; Denmark; and Barcelona, Spain. Patients over the age of 50 years were recruited consecutively from ophthalmologists' practices at the time of their enlistment for first-eye cataract surgery. Anticipated waiting time, opinions about personal waiting time, and patients' visual and health characteristics were identified by means of telephone interviews. The 550 patients interviewed at the time of enlistment for surgery anticipated waits varying from < 1 to 24 months. Clinical visual acuity measures were obtained from patients' ophthalmologists/cataract surgeons. Results indicated that anticipated waiting time was the strongest predictor of patients' tolerance of waiting for cataract surgery. Patient dissatisfaction increased with the duration of the anticipated wait. Patients in all three sites were accepting of waits of three months or less, and considered waits exceeding six months to be excessive. Response to waits between three and six months varied across study sites. Patients with low tolerance for waiting had greater self-reported difficulty with vision, as assessed by a Cataract Symptom Score and expressed trouble with vision. Patients' acceptance of waiting was not associated with clinical visual acuity measures or socio-demographic characteristics. The patient perspective on acceptability of waiting times for cataract surgery suggests that restricting waiting times to less than six months and preferably less than three months and utilizing self-reported measures of visual difficulty in prioritizing patients may contribute to improved management of waiting systems. Patients are more tolerant of their personal waiting times than responses to questions about waiting for elective surgery in general would indicate, and appear to accept waiting times that are longer than those identified as reasonable by specialists.

Aged↗
PubMed1997

Anxiety and depression in patients receiving implanted cardioverter-defibrillators: a longitudinal investigation.

OBJECTIVE: The implantable cardioverter-defibrillator (ICD) has dramatically improved survival rates following sudden cardiac death episodes. However, researchers have devoted little attention to the psychosocial consequences of living with the device. The current study used a longitudinal design to evaluate the impact of adaptation to the ICD on incidence and severity of anxiety and depression. METHOD: ICD recipients were administered standardized anxiety and depression questionnaires as well as questions evaluating quality of life related to the ICD in two consecutive yearly assessments. A preliminary evaluation of potentially important theoretical variables, such as the perceived predictability and controllability of shock onset was also conducted. RESULTS: One-third of the study population (N = 38) had clinically significant levels of anxiety, depressed mood, and fear of symptoms of autonomic arousal. These negative affective states persisted over time, with 40 to 63 percent of subjects continuing to have ongoing difficulties over a one-year time period. Anxiety about the ICD firing was closely associated with the occurrence of depression, while avoidance of activities was associated with anxiety. "Worry" about the ICD and a belief that ICD firing can be predicted were associated with anxiety sensitivity. CONCLUSIONS: Depressive and anxiety states in ICD recipients may be frequent, clinically significant, and resistant to spontaneous resolution. Early signs of anxiety and depression in ICD recipients should be evaluated. Implications for future research are discussed.

Adaptation, Psychological↗
PubMed1997

Characterization of antinucleolar antibody reactivity in patients with systemic sclerosis and their relatives.

OBJECTIVE: To study the prevalence and specificity of antinucleolar antibodies (ANoA) in patients with systemic sclerosis (SSc), their spouses, and their first-degree relatives, and to investigate whether SSc family members have greater frequency of ANoA than expected. METHODS: The sera of 58 SSc probands, 4 first-degree relatives with SSc, 215 first-degree relatives without SSc, and 24 spouses were screened for ANoA by indirect immunofluorescence (IF), and nucleolar antigens were characterized by immunoprecipitation (IP) of 35S methionine labeled K562 cell extracts. Sera from 118 randomly chosen family members without SSc were separately compared with 120 age and sex matched blood donor controls. RESULTS: Antinucleolar reactivity was detected by IF in 25 patients with SSc (40.3%), in 33 non-SSc relatives (15.3%), and in 4 spouses (16.7%). Twenty-four sera had autoantibodies to defined nucleolar antigens by IP (seven Pm-Scl, ten RNA polymerase (pol) I, four U3 RNP, three Th RNP), and all were from patients with SSc (38.7%). No serum had more than one type of nucleolar-specific autoantibody. Four sera had autoantibodies to topoisomerase I (topo I) and RNA pol II, one of which also recognized RNA pol I and RNA pol III. Antinucleolar IF was significantly more common in the unaffected first-degree relatives of patients with SSc (18.1%) than in controls (8.3%; p < 0.05). A small number of sera from both relatives and controls recognized bands by IP, none of which was identified as a SSc-specific autoantigen. CONCLUSION: Although antinucleolar reactivity is more common in the first-degree relatives of patients with SSc than controls, SSc associated ANoA are only present in patients with the disease, and appear to be mutually exclusive.

Antibodies, Antinuclear↗
PubMed1997

Practices associated with cataract surgery in Canada: results of a national survey.

OBJECTIVE: To examine Canadian ophthalmologists' reported practices related to cataract surgery. DESIGN: Mailed questionnaire survey. SETTING: Canada. PARTICIPANTS: Random sample of 698 ophthalmologists from the mailing list of the Canadian Ophthalmological Society. Of the 528 eligible ophthalmologists 353 completed the questionnaire (response rate 67%). A total of 276 respondents were classified as cataract surgeons (performed at least one cataract operation in the preceding year [1992]) and were included in the study. OUTCOME MEASURES: Reported use of preoperative ophthalmic tests, surgical technique, cataract anesthesia (including type of block and who administers it) and postoperative care. RESULTS: Most of the preoperative tests examined either were so routine as to be done in almost all cases or were rarely done at all. A total of 52% of the respondents were identified as predominantly extracapsular cataract extraction surgeons (ECCE), 46% as predominantly phacoemulsification surgeons and 2% as predominantly intracapsular cataract extraction surgeons. Overall, 57% of the respondents reported high use of retrobulbar anesthesia, 18% reported high use of peribulbar anesthesia, and 0.7% reported high use of general anesthesia. The mean number of postoperative visits in the first 4 months after surgery was 4.25. The mean rate of Nd:YAG laser capsulotomy in the first year after cataract surgery was 17.9%; 91% of the respondents reported a rate less than 40%. CONCLUSIONS: There seems to be limited use of nonessential preoperative ocular testing by Canadian cataract surgeons. Although ECCE remains the most common type of surgery performed, there appears to be a substantial number of surgeons trying phacoemulsification, and this will likely become the predominant technique in the near future. The self-reported practices of Canadian surgeons with relation to preoperative testing and postoperative follow-up appear to be consistent with the Clinical Practice Guideline for cataract surgery set by the US Agency for Health Care Policy and Research. However, variations in the number of postoperative visits and Nd:YAG capsulotomy rates merit further investigation.

Anesthesia, Local↗
PubMed1996

How many general surgeons do you need in rural areas? Three approaches to physician resource planning in southern Manitoba.

OBJECTIVE: To assess critically the results of using three different approaches to planning for the number of general surgeons in rural areas. DESIGN: Estimates of the number of general surgeons needed using a ratio approach, a and a population-needs-based approach. SETTING: Rural southern Manitoba. OUTCOME MEASURE: Number of general surgeons needed. RESULTS: The ratio approach supported the recruitment of 7.8 to 14.5 additional general surgeons to rural southern Manitoba. The repatriation approach suggested that the area might support five additional general surgeons, if residents could be persuaded to undergo their surgery closer to home. The population-needs-based approach suggested that the health status of area residents was similar to that of residents of other areas of the province and that they had a higher rate of surgery than residents of other areas; no additional surgeons were apparently needed. CONCLUSIONS: Each method has certain advantages, and none is necessarily useful in isolation. Hence, the most effective approach to planning for general surgeons is likely a combination of all three methods. Other factors that may be important include the type of payment structure and the need for professional groups to monitor variations in rates of surgery.

Aged↗
PubMed1996

A Cross-Task Comparison of False Belief Understanding in a Head Start Population

This research had two main goals: to compare different methods of assessing understanding of false belief and to extend the study of false belief to the population served by Project Head Start. Across two experiments the participants were ninety 3-, 4-, and 5-year-old children, drawn from low-income, primarily African-American families. Each child responded to a battery of false belief tasks that varied in the type of belief in question (contents tasks versus locations tasks), the target for the belief ascription (own belief versus other's belief), the method of presenting the reality information (visual versus verbal), and the presence or absence of a deception context. Performance was better on locations tasks than on contents tasks and among older children compared to younger children; the other comparisons resulted in smaller and less consistent effects. Despite the improvement with age, the level of performance fell short of that typically reported in the literature. Although correlations among tasks were significant, fewer than half of the children performed consistently across the problems.

Journal Article↗
PubMed1996

Experimental evaluation of a modular approach to mobilizing antitobacco influences of peers and parents.

The experimental evaluation of two components of a community intervention to prevent adolescent tobacco use are described. Youth antitobacco activities (e.g., peer quizzes, sidewalk art, poster and T-shirt giveaways, etc.) and family communications activities (pamphlets to parents and student quizzes of parents) were evaluated in two time-series experiments, each of which was conducted in two experimental and one control community. Students in Grades 6 and 8 and their parents were assessed in a series of four phone surveys in the first experiment and six phone surveys in the second. Implementation of the youth antitobacco and family communications activities led to significantly greater exposure of young people to antitobacco information. They led to increases in parent and youth knowledge about tobacco use and more negative attitudes toward tobacco. In Experiment 2, youths in intervention communities had significantly lower rated intentions to smoke. The findings suggest the value of a modular approach to community interventions for influencing the social context relevant to the onset of adolescent tobacco use.

Adolescent↗
PubMed1996

A potent far-upstream enhancer in the mouse pro alpha 2(I) collagen gene regulates expression of reporter genes in transgenic mice.

We have identified three DNase I-hypersensitive sites in chromatin between 15 and 17 kb upstream of the mouse pro alpha 2 (I) collagen gene. These sites were detected in cells that produce type I collagen but not in cells that do not express these genes. A construction containing the sequences from -17 kb to +54 bp of the mouse pro alpha 2 (I) collagen gene, cloned upstream of either the Escherichia coli beta-galactosidase or the firefly luciferase reporter gene, showed strong enhancer activity in transgenic mice when compared with the levels seen previously in animals harboring shorter promoter fragments. Especially high levels of expression of the reporter gene were seen in dermis, fascia, and the fibrous layers of many internal organs. High levels of expression could also be detected in some osteoblastic cells. When various fragments of the 5' flanking sequences were cloned upstream of the 350-bp proximal pro alpha 2(I) collagen promoter linked to the lacZ gene, the cis-acting elements responsible for enhancement were localized in the region between -13.5 and -19.5 kb, the same region that contains the three DNase I-hypersensitive sites. Moreover, the DNA segment from -13.5 to -19.5 kb was also able to drive the cell-specific expression of a 220-bp mouse pro alpha 1(I) collagen promoter, which is silent in transgenic mice. Hence, our data suggest that a far-upstream enhancer element plays a role in regulating high levels of expression of the mouse pro alpha 2(I) collagen gene.

3T3 Cells↗
PubMed1996

Survival following the onset of scleroderma: results from a retrospective inception cohort study of the UK patient population.

Scleroderma is a multisystem disease which in many populations is reported to have a substantially reduced survival. One problem with many of the published studies is the inclusion of patients with differing lengths of disease at baseline, with the possibility of left censorship bias. The aim was to determine the survival and its predictors in a cohort of scleroderma patients with new onset of disease. All 283 new patients referred to one of the authors (CMB) who had a reported disease onset after 1 January 1982 were studied. Detailed clinical and laboratory information at baseline and at 1 yr were extracted from the structured records. Vital status as at 1 December 1993 was determined using the UK's NHS Central Register. Expected numbers of deaths were obtained by applying local age and sex all-cause mortality rates. In total, there were 1871 person-years of follow-up with crude mortality rates of 3.9 and 2.6%/year, respectively, in males and females. The mortality rate remained approximately constant over the first 10 yr of follow-up. In comparison with expected survival, based on the age distribution of the cohort, there was an overall 4-fold increased mortality rate in this group which was higher in females [standardized mortality ratio (SMR) 4.6, 95% CI 3.2-6.2] than in males (SMR 3.2, 95% CI 1.8-5.0). Analysis of cause-specific mortality showed that 79% of the excess deaths were scleroderma related, but this proportion was substantially lower in males than in females (67% vs 83.9%). These data confirm the increased mortality rate associated with scleroderma, but these rates are lower than those reported from other centres. Females have a higher age-adjusted mortality which is reflected in the different pattern of mortality between the sexes.

Cohort Studies↗
PubMed1996

Relapse prevention by means of paroxetine in ECT-treated patients with major depression: a comparison with imipramine and placebo in medium-term continuation therapy.

In-patients with severe major depression were treated in the acute phase with electroconvulsive therapy (ECT) in combination with antidepressants. The drug treatment consisted of two randomized trials which were both extended into the post-ECT continuation phase. Patients with electrocardiological impairment were randomized to either 30 mg paroxetine daily or placebo under blind conditions. Patients without electrocardiological impairment were randomized to either 30 mg paroxetine daily or 150 mg imipramine daily. There was a high level of agreement between the Hamilton Depression Scale and the Melancholia Scale, demonstrating that the patients treated with ECT plus imipramine in the acute phase showed greater symptom reduction than those treated with ECT plus paroxetine. However, in the post-ECT phase paroxetine was superior to both imipramine and placebo in preventing relapse. Thus in the post-ECT phase 65% of the placebo-treated patients relapsed, compared to 30% of the imipramine-treated patients and 10% of the paroxetine-treated patients. The psychometric analysis of the Melancholia Scale in the continuation or post-ECT phase showed that relapsing patients displayed a pattern with lack of interests, impaired concentration, depressed mood and anxiety among the less severe symptoms (first-compartment symptoms). In other words, these symptoms represent the gate to full-blown depression (second-compartment symptoms). Serotonin-selective antidepressants such as paroxetine appear to be more effective in controlling the first-compartment symptoms.

Adult↗
PubMed1996

Population health and health care use: an information system for policy makers.

University-based researchers in Manitoba, Canada, have used administrative data routinely collected as part of the national health insurance plan to design a population-based health information system (POPULIS). Decision-makers can use this system to make critical comparisons across regions of residents' health status, socioeconomic risk characteristics, and use of hospitals, nursing homes, and physicians. Policy makers have found this information system useful in providing answers to questions they are often asked: Which populations need more physician services? Which need fewer? Are high-risk populations poorly served or do they have poor health outcomes despite being well served? Does high utilization represent overuse or is it related to high need? Three commentaries follow.

Database Management Systems↗
PubMed1996

Continuity of pediatric ambulatory care in a universally insured population.

OBJECTIVE: To describe the prevalence of continuity of care over a 5-year period in a complete cohort of urban children universally insured for medical care provided under fee-for-service reimbursement. METHOD: All children enrolled in the study were born to women living in metropolitan Winnipeg between July 1, 1987 and December 31, 1988 (N = 12,590). All ambulatory physician services for this group were enumerated from computerized administrative databases for the period from birth through 60 months. Continuity of care, defined as the proportion of total care provided by the most frequently seen physician or physician practice over time, was calculated for each child. Descriptive analyses include an examination of maternal and household characteristics associated with children receiving 80% or more of total ambulatory care from a single provider source. RESULTS: From birth to 24 months, 51% of children received at least 80% of ambulatory visits from a single provider practice. This proportion of the children declined to 28% at 25 through 60 months. Children living in low-income neighborhoods had poorer continuity profiles. Other household factors associated with poor continuity included young maternal age, single maternal marital status, residential mobility, and inadequate maternal use of prenatal medical care. Households affiliated with pediatric practices had better continuity profiles than households affiliated with general medical practices. CONCLUSION: Despite universal medical insurance, barriers to a longitudinally continuous relationship with a primary care provider remain in this setting. Although this study has emphasized the description of those barriers associated with household characteristics, there is evidence that factors related to the organization and delivery of medical care are also relevant.

Adult↗
PubMed1995

Community perceptions of adolescent health and sexuality. Results from a southern community-based project.

OBJECTIVE: To describe the attitudes about adolescent health issues, especially school-based health services, held by adults in a rural community. DESIGN: "Before-after," quasi-experimental design involving independent, cross-sectional population-based surveys in 1989 and 1992. SETTING: Rural county located in the southeastern United States. PARTICIPANTS: Probability sample of adults, 18 years and older, who were residents of the county, including 831 respondents in the first survey and 210 respondents in the second survey. INTERVENTION: County-wide public education campaign involving public service announcements on television and radio, newspaper advertisements, posters, and open-to-the-public adolescent health programs and events. MAIN OUTCOME MEASURES: Attitudes about the types of health services that should be included in a public school-based adolescent health program. RESULTS: Rural adults' attitudes toward public school-based adolescent health services were similar before and after the community-wide campaign. Respondents believed the public schools should provide teenagers with information and counseling on substance abuse, sexual activity, birth control, and the acquired immunodeficiency syndrome but should not provide primary health care or birth control products. Most adults believed that sex and acquired immunodeficiency syndrome education should begin before high school. CONCLUSIONS: A comprehensive, public school-based adolescent health program providing health information but not health services may be acceptable to this community. Adults' attitudes about adolescent health issues do not appear to have been modified by the adolescent health awareness campaign.

Adolescent↗
PubMed1995

Scleroderma-derived human fibroblasts retain abnormal phenotypic and functional characteristics following retroviral transduction with the SV40 tsT antigen.

In this study an amphotropic retrovirus has been used to efficiently transduce normal human (NF) and scleroderma (systemic sclerosis; SSc) dermal fibroblasts (SScF) with a sequence encoding a temperature-sensitive mutant of the SV40 large T antigen (tsA58-U19). From the primary outgrowths of skin explants, cultures were generated whose growth was stringently temperature-dependent. When grown at a low, permissive temperature (35 degrees C), both normal and SSc-transduced cells continuously divided with similar doubling times, whereas at a high, nonpermissive temperature (39.5 degrees C), division of both the NF and SScF cells was rapidly arrested. These cells have been passaged more than 50 times, have the typical morphological appearance of fibroblasts, and have retained an anchorage-dependent phenotype. The transduced normal cells (tsT-NF) synthesized the matrix molecules collagen and fibronectin and expressed phenotypic antigens characteristic of their nontransduced counterparts, including MHC Class I, VLA beta 1 (CD29), Hermes 1 (CD44), VLA-4 alpha (CD49d), ICAM-1 (CD54) and LFA-3 (CD58) and the cell surface ectoenzymes neutral endopeptidase (CD10), aminopeptidase N (CD13), and dipeptidyl peptidase IV (CD26). Analysis of the transduced SSc fibroblasts (tsT-SScF) showed that these cells exhibited certain major features of the SSc pathology, notably the abnormally high synthesis of type I collagen, increased expression of ICAM-1, and depressed levels of CD26. Moreover, these phenotypic characteristics were retained even after prolonged culture in vitro. The tsT-SScF cells also retained their responsiveness to cytokines, since interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) both produced a marked increase in ICAM-1 expression. Our findings show that infection of SScF with the SV40 tsT antigen extends the life span of these cells and does not ablate their abnormal phenotypic and functional characteristics.

Antibodies↗