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Strand V, Cohen S, Crawford B, Smolen JS, Scott DL. Patient-reported outcomes better discriminate active treatment from placebo in randomized controlled trials in rheumatoid arthritis. Rheumatology (Oxford) 2004; 43:640-7. [PMID: 15039493 DOI: 10.1093/rheumatology/keh140] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Recent randomized controlled trials (RCTs) in rheumatoid arthritis (RA) have used patient- and physician-reported outcomes, ESR and/or CRP as components of ACR response criteria to assess efficacy. OBJECTIVES Mean changes from baseline in patient- and physician-reported outcome measures, ESR and CRP were compared in two RCTs in patients with active RA. Comparisons between active and placebo treatment used mean percentage improvements and standard effect sizes (SESs). RESULTS In both protocols, patient-reported assessments of disease activity, pain and physical function reflected little or no improvement with placebo, best discriminating between active and placebo therapy, as did ESR and CRP. CONCLUSION Improvements in signs and symptoms of active RA in placebo RCTs appear to be best reflected by patient-reported measures of physical function, as long as reported changes in global assessments of disease activity and/or pain reflect similar benefit. Patient-reported outcome measures should be considered objective; treatment-associated changes are congruent with measures of inflammation, and appear less susceptible to the placebo response.
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Strand V, Aranow C, Cardiel MH, Alarcón-Segovia D, Furie R, Sherrer Y, Tumlin J, Wallace DJ, Crawford B. Improvement in health-related quality of life in systemic lupus erythematosus patients enrolled in a randomized clinical trial comparing LJP 394 treatment with placebo. Lupus 2004; 12:677-86. [PMID: 14514130 DOI: 10.1191/0961203303lu440oa] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In a 76-week, randomized controlled trial, patients received 100 mg LJP 394 or placebo weekly for 16 weeks followed by three 12-week treatment cycles of 50 mg LJP 394 or placebo weekly each separated by eight-week periods when no therapy was administered. Health-related quality of life (HRQOL) was assessed using SF-36 at baseline, 16 weeks and every 12 weeks thereafter. Analyses populations included intent to treat (ITT) (n = 179) and patients with high-affinity anti-dsDNA antibody binding (HA): 157/179; 85% active, 90% placebo. In the ITT population, there were improvements in role emotional (RE) (+7.3 versus -8.2), social functioning (SF) (+4.3 versus +0.7), and role physical (RP) (+11.3 versus +6.0) domains in the active treatment group when compared with placebo, with similar changes observed in the HA population. In 37 patients with data pre- and post-renal flares, those receiving LJP 394 reported stabilization or improvement in all but one domain compared with deterioration in all domains with placebo. Changes in RE domain scores following a flare differed by 22.7 points between the two treatment groups, favouring LJP 394 treatment. Patients receiving LJP 394 reported stable or improved HRQOL with active treatment following renal flares compared with deterioration in placebo. Differences between treatment groups in RE and SF domains are clinically important and were replicated irrespective of the protocol population analysed.
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Pincus T, Strand V, Koch G, Amara I, Crawford B, Wolfe F, Cohen S, Felson D. An index of the three core data set patient questionnaire measures distinguishes efficacy of active treatment from that of placebo as effectively as the American College of Rheumatology 20% response criteria (ACR20) or the Disease Activity Score (DAS) in a rheumatoid arthritis clinical trial. ARTHRITIS AND RHEUMATISM 2003; 48:625-30. [PMID: 12632413 DOI: 10.1002/art.10824] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE To evaluate the capacity of a pooled index of only the 3 patient self-report questionnaire measures among the 7 American College of Rheumatology (ACR) core data set (Core Data Set) measures to distinguish efficacy of active treatment of rheumatoid arthritis (RA) with leflunomide or methotrexate versus placebo in a randomized, controlled clinical trial, and to compare the results with those obtained using the ACR 20% response criteria (ACR20), Disease Activity Score (DAS), and other pooled indices. METHODS The 7 ACR Core Data Set measures of 1) joint swelling, 2) joint tenderness, 3) physician global assessment, 4) erythrocyte sedimentation rate (ESR), 5) functional disability, 6) pain, and 7) patient global assessment were combined into the following 5 pooled indices: "All Core Data Set" (all 7 measures), "Assessor Only" (measures 1-3), "Assessor + ESR" (measures 1-4), "Patient Only" (measures 5-7), and "Patient + ESR" (measures 4-7). The capacity of each of these 5 indices to detect differences between active treatment and placebo treatment was compared with that of the ACR20 and the DAS using 4 different analytic methods, each of which presented advantages and limitations. Agreement of the indices with one another and with the ACR20 and the DAS was analyzed according to pairwise kappa statistics and Z scores in multivariate logistic regression models. RESULTS Each of the 5 indices, including "Patient Only," had a similar capacity to detect greater efficacy of leflunomide and methotrexate versus placebo in this clinical trial, according to each of 4 methods, at similar levels of statistical and clinical significance. CONCLUSION A pooled index of patient self-report questionnaire Core Data Set measures appears to be as informative as ACR20 responses, DAS scores, and pooled indices of all and assessor-derived Core Data Set measures for distinguishing between active treatment and placebo treatment in this RA clinical trial.
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Crawford B. The dawn of a deluge. WOMEN ALIVE (LOS ANGELES, CALIF.) 2002:2, 5, 8 passim. [PMID: 11682988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
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McLay R, Klingsberg R, Florez L, Bhattacharjee M, Garcia C, Sutton C, Crawford B. A web page to teach neurology and neuropathology to medical students. Neuropathol Appl Neurobiol 2001; 27:142-4. [PMID: 11437995 DOI: 10.1046/j.1365-2990.2001.00320.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Sam W, Qin H, Crawford B, Yue D, Yu S. Homozygosity for a 4-bp deletion in a patient with Wolfram syndrome suggesting possible phenotype and genotype correlation. Clin Genet 2001; 59:136-8. [PMID: 11260218 DOI: 10.1034/j.1399-0004.2001.590214.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Zwerdling T, Davies S, Lazar L, Crawford B, Tucker L, Boughner A, Richter-Beck L. Unique aspects of caring for dying children and their families. Am J Hosp Palliat Care 2000; 17:305-11. [PMID: 11886054 DOI: 10.1177/104990910001700507] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Pediatric hospice has become an important service for children and their families in the past decade. In this article we present unique aspects of StarShine, the hospice of Children's Hospital Medical Center in Cincinnati, Ohio. Length-of-service data demonstrate the need to find innovative ways of encouraging earlier referral to hospice. Several specialized aspects of care, such as long-term bereavement, pet visitation and social services for the family are presented. The initiation of a novel in-home pain management program is described. StarShine has not followed an adult hospice model, and as such, we discuss those unique aspects of dying pediatric patients and suggest specific solutions and interventions designed for children.
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Yeh HH, Tian T, Rubio L, Crawford B, Falk BW. Asynchronous accumulation of lettuce infectious yellows virus RNAs 1 and 2 and identification of an RNA 1 trans enhancer of RNA 2 accumulation. J Virol 2000; 74:5762-8. [PMID: 10846054 PMCID: PMC112069 DOI: 10.1128/jvi.74.13.5762-5768.2000] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2000] [Accepted: 04/17/2000] [Indexed: 11/20/2022] Open
Abstract
Time course and mutational analyses were used to examine the accumulation in protoplasts of progeny RNAs of the bipartite Crinivirus, Lettuce infectious yellow virus (LIYV; family Closteroviridae). Hybridization analyses showed that simultaneous inoculation of LIYV RNAs 1 and 2 resulted in asynchronous accumulation of progeny LIYV RNAs. LIYV RNA 1 progeny genomic and subgenomic RNAs could be detected in protoplasts as early as 12 h postinoculation (p.i.) and accumulated to high levels by 24 h p.i. The LIYV RNA 1 open reading frame 2 (ORF 2) subgenomic RNA was the most abundant of all LIYV RNAs detected. In contrast, RNA 2 progeny were not readily detected until ca. 36 h p.i. Mutational analyses showed that in-frame stop codons introduced into five of seven RNA 2 ORFs did not affect accumulation of progeny LIYV RNA 1 or RNA 2, confirming that RNA 2 does not encode proteins necessary for LIYV RNA replication. Mutational analyses also supported that LIYV RNA 1 encodes proteins necessary for replication of LIYV RNAs 1 and 2. A mutation introduced into the LIYV RNA 1 region encoding the overlapping ORF 1B and ORF 2 was lethal. However, mutations introduced into only LIYV RNA 1 ORF 2 resulted in accumulation of progeny RNA 1 near or equal to wild-type RNA 1. In contrast, the RNA 1 ORF 2 mutants did not efficiently support the trans accumulation of LIYV RNA 2. Three distinct RNA 1 ORF 2 mutants were analyzed and all exhibited a similar phenotype for progeny LIYV RNA accumulation. These data suggest that the LIYV RNA 1 ORF 2 encodes a trans enhancer for RNA 2 accumulation.
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Evans CJ, Crawford B. Data collection methods in prospective economic evaluations: how accurate are the results? VALUE IN HEALTH : THE JOURNAL OF THE INTERNATIONAL SOCIETY FOR PHARMACOECONOMICS AND OUTCOMES RESEARCH 2000; 3:277-86. [PMID: 16464192 DOI: 10.1046/j.1524-4733.2000.34005.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
OBJECTIVES Often in economic evaluations a division is made between those studies that have a high level of accuracy versus those that are easily generalized. This interstudy dichotomy is often translated into prospective, randomized controlled trials with high internal validity and observational and modeling studies with a high level of external validity. This article challenges this conventional view and examines intrastudy effects on validity. METHOD A review and summary of the literature was conducted in order to assess the impact that data collection strategies will have on internal validity. Two scenario models were created in order to gain a preliminary understanding of the magnitude of the problem. RESULTS Data collection strategies have an impact on the level of internal validity found in an economic evaluation. Comparisons of studies that are prospective in nature is misleading as data collection strategy can lead to different resource and cost estimates even when all other relevant factors are similar. It is possible to shift and improve the level of validity by combining different collection methods. CONCLUSIONS Instead of viewing internal and external validity as polar opposites, validity should be considered in terms of a continuum within a particular study. The use of proxies to collect resource utilization estimates, the reliance on patient self-reported data, and the method of collecting this type of data all impact the validity of study results. National guidelines for the economic evaluation of agents and devices should consider this issue in more depth, and existing evidence rankings should be adapted to be more appropriate to pharmacoeconomic studies.
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Evans C, Crawford B. Expert judgement in pharmacoeconomic studies. Guidance and future use. PHARMACOECONOMICS 2000; 17:545-53. [PMID: 10977393 DOI: 10.2165/00019053-200017060-00002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Research in the field of pharmacoeconomics has increased substantially during the past decade. Much of this research has been on the design and analysis of data concerning the relative merits of one drug or device compared with another in terms of costs and effects. Concomitant with these evaluations has been the development of guidelines for the conduct of economic evaluations in several countries. However, despite an increase in research, little attention has been paid to how different study designs may influence the results of a study. The use of expert judgement in decision analytic modelling is one area where design issues may influence the findings of a study. This issue is examined for the case of modified Delphi and Delphi panels. Although the use of expert opinion in modelling studies seems to be widespread, there is little consistent application, understanding or reporting of the techniques used. In particular, the definitions of techniques vary between studies, the criteria for determining when consensus is reached vary, and the reporting of these criteria is absent. Future studies using expert judgement should be more aware of the controversies surrounding the issue and provide more reporting of the techniques used. It is proposed that future validation exercises may assist researchers in determining the most appropriate application of methods.
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Kuerer HM, Hwang ES, Anthony JP, Dudley RA, Crawford B, Aubry WM, Esserman LJ. Current national health insurance coverage policies for breast and ovarian cancer prophylactic surgery. Ann Surg Oncol 2000; 7:325-32. [PMID: 10864338 DOI: 10.1007/s10434-000-0325-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND The efficacy of prophylactic mastectomy and oophorectomy in reducing breast and ovarian carcinoma has recently been reported in high-risk women. Because cost has become central to medical decision-making, this study was designed to evaluate currently existing coverage policies for these procedures. METHODS A confidential detailed cross-sectional nationwide survey of 481 medical directors from the American Association of Health Plans, Medicare, and Medicaid was conducted. RESULTS Of the 150 respondents, 65% (n = 97) had 100,000 or more enrolled members and 35% (n = 53) had fewer than 100,000 enrolled members. Only 44% of private plans have specific policies for coverage of prophylactic mastectomy for a strong family history of breast cancer and 38% of plans for a BRCA mutation. Only 20% of total responding plans had a policy for coverage of prophylactic oophorectomy under any clinical circumstance. Governmental carriers were significantly less likely to have any policy for prophylactic surgery (range, 2%-12%) compared with nongovernmental plans (range, 24%-44%; P < .001). No significant regional differences for coverage policies were identified (P > .05). CONCLUSIONS Significant variations currently exist for health insurance coverage of prophylactic mastectomy and oophorectomy. As genetic testing becomes widespread, more uniform policies should be established to enable appropriate high-risk candidates equal access and coverage for these procedures.
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Tugwell P, Wells G, Strand V, Maetzel A, Bombardier C, Crawford B, Dorrier C, Thompson A. Clinical improvement as reflected in measures of function and health-related quality of life following treatment with leflunomide compared with methotrexate in patients with rheumatoid arthritis: sensitivity and relative efficiency to detect a treatment effect in a twelve-month, placebo-controlled trial. Leflunomide Rheumatoid Arthritis Investigators Group. ARTHRITIS AND RHEUMATISM 2000; 43:506-14. [PMID: 10728742 DOI: 10.1002/1529-0131(200003)43:3<506::aid-anr5>3.0.co;2-u] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE To examine correlations between clinical improvement as defined by the American College of Rheumatology (ACR) responder analysis and clinical improvement as determined by 4 function and/or health-related quality of life measures, and to estimate the sensitivity and relative efficiency of these measures compared with changes in the tender joint count in patients with rheumatoid arthritis (RA). METHODS A 52-week, multicenter, double-blind controlled trial was conducted to compare treatment with leflunomide (n = 182), methotrexate (n = 180), or placebo (n = 118) in patients with active RA. ACR response rates and improvement in scores on the Health Assessment Questionnaire (HAQ), Problem Elicitation Technique (PET), and Medical Outcomes Survey Short Form 36 (SF-36) were compared in 438 of the patients. RESULTS In comparing leflunomide with placebo, the patient global assessment, HAQ disability index, and SF-36 bodily pain scale were most responsive to treatment group differences. The modified HAQ (M-HAQ), PET Top 5, SF-36 physical component score, physician global assessment, pain intensity scale, and SF-36 physical functioning scale were more responsive to treatment group differences than was the tender joint count. In comparing methotrexate with placebo, the patient and physician global assessments were most responsive. These 2 measures, as well as the pain intensity scale and the C-reactive protein level, were more responsive to treatment group differences than was the tender joint count, while the SF-36 mental health component score was least responsive. A close correlation between changes in the M-HAQ and HAQ scores indicated that the M-HAQ was similarly responsive to change over time. Improvements in the PET, SF-36 physical component score, bodily pain, and physical functioning scales correlated with the ACR responder status. CONCLUSION Both disease-specific and generic measures of function and health-related quality of life detect improvements in RA patients. Using both types of measures for evaluating therapies will identify discernible changes that are important to patients, and will facilitate comparisons across different disease states.
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Addison C, Crawford B. Not bad, just misunderstood. NURSING TIMES 1999; 95:52-3. [PMID: 10847085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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Northwood IC, Tong AH, Crawford B, Drobnies AE, Cornell RB. Shuttling of CTP:Phosphocholine cytidylyltransferase between the nucleus and endoplasmic reticulum accompanies the wave of phosphatidylcholine synthesis during the G(0) --> G(1) transition. J Biol Chem 1999; 274:26240-8. [PMID: 10473578 DOI: 10.1074/jbc.274.37.26240] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The transition from quiescence (G(0)) into the cell division cycle is marked by accelerated phospholipid turnover. We examined the rates of phosphatidylcholine (PC) synthesis and the activity, membrane affinity, and intracellular localization of the rate-limiting enzyme in the synthesis of PC, CTP:phosphocholine cytidylyltransferase (CT) during this transition. The addition of serum to quiescent IIC9 fibroblasts resulted in a wave of PC synthesis beginning at approximately 10 min, peaking at approximately 3 h with a >10-fold increase in rate, and declining to near basal rates by 10 h. CT activity, monitored in situ, was elevated approximately 3-fold between 1 and 2 h postserum. Neither CT mass nor its phosphorylation state changed during the surge in PC synthesis and CT activity. On the other hand, the ratio of particulate/soluble CT surged and then receded in concert with the wave of PC synthesis. During quiescence, CT was confined to the nucleus, as assessed by indirect immunofluorescence. Within 10 min after serum stimulation, a portion of the CT fluorescence appeared in the cytoplasm, where it intensified until approximately 4 h postserum. Thereafter, the cytoplasmic CT signal waned, while the nuclear signal increased, and by 8 h CT was once again predominantly nuclear. The dynamics of CT's apparent translocation in and out of the nucleus paralleled the wave of PC synthesis and the solubility changes of CT. Cytoplasmic CT co-localized with BiP, a resident endoplasmic reticulum protein, in a double labeling experiment. These data suggest that the wave of PC synthesis that accompanies the G(0) --> G(1) transition is regulated by the coordinated changes in CT activity, membrane affinity, and intracellular distribution. We describe for the first time a redistribution of CT from the nucleus to the ER that correlates with an activation of the enzyme. We propose that this movement is required for the stimulation of PC synthesis during entry into the cell cycle.
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Strand V, Tugwell P, Bombardier C, Maetzel A, Crawford B, Dorrier C, Thompson A, Wells G. Function and health-related quality of life: results from a randomized controlled trial of leflunomide versus methotrexate or placebo in patients with active rheumatoid arthritis. Leflunomide Rheumatoid Arthritis Investigators Group. ARTHRITIS AND RHEUMATISM 1999; 42:1870-8. [PMID: 10513801 DOI: 10.1002/1529-0131(199909)42:9<1870::aid-anr11>3.0.co;2-d] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
OBJECTIVE To assess the efficacy of leflunomide or methotrexate compared with placebo in improving function and health-related quality of life in patients with active rheumatoid arthritis (RA), and to examine correlations between response status (as defined by the American College of Rheumatology [ACR] response criteria) and improvement in these measures. METHODS This 52-week, multicenter, doubleblind, controlled trial compared responses to the Health Assessment Questionnaire (HAQ), modified Health Assessment Questionnaire (MHAQ), Problem Elicitation Technique (PET), Medical Outcomes Study Short Form 36 (SF-36), and questions regarding work productivity among 3 treatment groups (leflunomide, methotrexate, and placebo). Improvement in the PET top 5 and SF-36 scales and component scores were compared with ACR response rates. RESULTS Clinically meaningful and statistically significant (P<0.0001) improvement in measures of function and heath-related quality of life (MHAQ scores, all scales and disability index of the HAQ, weighted top 5 score of the PET, 5 of 8 scales and physical component score of the SF-36, and work productivity) was seen during treatment with leflunomide in comparison with placebo. Methotrexate administration resulted in significant improvements (P<0.05) in comparison with placebo in the MHAQ scores, HAQ disability index, weighted top 5 score of the PET, physical component score of the SF-36, and bodily pain scale. Compared with methotrexate, leflunomide administration resulted in significantly (P<0.01) more improvement in the MHAQ scores, 5 of 8 scales and disability index of the HAQ, weighted top 5 score of the PET, and 2 of 8 scales and physical component score of the SF-36. Improvements in the PET score, SF-36 physical component score, and work productivity correlated with the ACR responder rates of > or =20% and > or =50% improvement. CONCLUSION Significant improvements in function and health-related quality of life occurred in patients with RA during treatment with leflunomide or methotrexate. These findings were clinically meaningful and correlated with the ACR response status.
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Crawford B. Alison Bell Memorial Award. Highlighting the role of the perioperative nurse--is preoperative assessment necessary? THE BRITISH JOURNAL OF THEATRE NURSING : NATNEWS : THE OFFICIAL JOURNAL OF THE NATIONAL ASSOCIATION OF THEATRE NURSES 1999; 9:309-12. [PMID: 10614199 DOI: 10.1177/175045899900900703] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Tian T, Rubio L, Yeh HH, Crawford B, Falk BW. Lettuce infectious yellows virus: in vitro acquisition analysis using partially purified virions and the whitefly Bemisia tabaci. J Gen Virol 1999; 80 ( Pt 5):1111-1117. [PMID: 10355756 DOI: 10.1099/0022-1317-80-5-1111] [Citation(s) in RCA: 130] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Virions of lettuce infectious yellows virus (LIYV; genus Crinivirus) were purified from LIYV-infected plants and their protein composition was analysed by SDS-PAGE and immunoblotting. Virion preparations contained the major capsid protein (CP), but the minor capsid protein (CPm), p59 and the HSP70 homologue were also identified by immunoblot analysis. Immunogold labelling analysis showed that CP constituted the majority of the LIYV virion capsid, but CPm was also part of the capsid and localized to one end of the virion, similar to the polar morphology seen for viruses in the genus Closterovirus. p59 and the HSP70 homologue were not detected on virions by immunogold labelling, but were always detected in virion preparations by immunoblot analysis. Purified LIYV virions were used for in vitro acquisition analysis with Bemisia tabaci whiteflies and were efficiently transmitted to plants. Infectivity neutralization analyses were done using antisera to the LIYV-encoded CP, CPm, p59 and HSP70 homologue. Only antiserum to the CPm effectively neutralized LIYV transmission by B. tabaci. These data suggest that the LIYV-B. tabaci transmission determinants are associated with purified virions, and that the LIYV virion structural protein CPm is involved in transmission by B. tobaci.
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Evans C, Crawford B. Patient self-reports in pharmacoeconomic studies. Their use and impact on study validity. PHARMACOECONOMICS 1999; 15:241-256. [PMID: 10537432 DOI: 10.2165/00019053-199915030-00004] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The validity of estimates of resource utilisation based on patient recall has not been firmly established. A comprehensive literature search was conducted to identify studies that used patient self-reports to derive estimates of healthcare resource utilisation, direct nonmedical costs and indirect costs. Previous work in this area was examined to determine the issues that were most important in determining whether patient self-reports lead to valid and unbiased estimates in cost-effectiveness studies. This study reviews and highlights areas where patient self-reports lead to reliable estimates and where their use may lead to erroneous conclusions. In particular, it is noted that patient recall of resource utilisation declines over time, that the salience of a treatment episode affects recall and that the perceived social acceptability of a condition and other confounding factors may influence patient reporting. Moreover, it appears that not all elements of healthcare consumption are recalled to the same degree: medication use tends to be recalled with less accuracy than hospitalisation. In terms of the potential impact on cost-effectiveness results, the main concern is with problems of validity rather than bias, although bias may occur when the results are applied to league tables.
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Tunc M, Char DH, Crawford B, Miller T. Intraepithelial and invasive squamous cell carcinoma of the conjunctiva: analysis of 60 cases. Br J Ophthalmol 1999; 83:98-103. [PMID: 10209445 PMCID: PMC1722787 DOI: 10.1136/bjo.83.1.98] [Citation(s) in RCA: 143] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIM To evaluate the clinical features, treatment results, and recurrence rates in patients with either intraepithelial or invasive squamous cell carcinoma of the conjunctiva. METHODS Retrospective analysis of 60 cases (22 conjunctival intraepithelial and 38 invasive squamous cell carcinomas) to determine patterns of clinical presentation, aetiological factors, and treatment results. The mean patient age was 64 years old. 70% of the patients were male. Patients were treated with a variety of therapies, depending on the degree of tumour involvement; most cases were treated with frozen section controlled excision and adjunctive cryotherapy. Modified eye wall resection or enucleation was done for intraocular invasion and exenteration was done for orbital involvement. RESULTS Red eye (68%) and ocular irritation (57%) were the most common presenting symptoms. 44% of the patients had other eye findings consistent with extensive solar exposure. 20% of the patients had a history of malignant skin tumours. Visceral malignancies developed in 8%. Scleral involvement was present in 14 (37%), intraocular involvement in five (13%), and orbital invasion in four (11%) cases with invasive squamous cell carcinoma. After a mean follow up of 56 months (18-226 months) the rate of new or recurrent tumours was 4.5% for intraepithelial squamous carcinoma and 5.3% for invasive squamous cell carcinoma. No patient developed metastases or tumour related deaths. CONCLUSION Excision with intraoperative control of the surgical margins and adjunctive cryotherapy results in good tumour control rates.
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Crawford B, Martin C. Ultrastructure and differentiation of the larval esophageal muscle cells of the starfishPisaster ochraceus. J Morphol 1998; 237:1-18. [DOI: 10.1002/(sici)1097-4687(199807)237:1<1::aid-jmor1>3.0.co;2-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Crawford B. Clinical economics and sleep disorders. Sleep 1997; 20:829-34. [PMID: 9415941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Sleep disorders have been shown to have substantial psychosocial sequelae with large economic impact. Numerous studies have examined the psychosocial aspects of sleep disorders; however, there has been little published on the associated economic implications. With increasing pressure to contain health care expenditures and provide value for the dollar, clinical economics is playing an important role in the decision-making process about alternative strategies within health care organizations. There are several strategies one may pursue to examine the economics of medical interventions. The predominant strategies include: cost identification, cost effectiveness, cost utility, and cost benefit. This review provides a basis for performing clinical economic evaluations in sleep disorders.
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Burke CC, Gullatte MM, Vigliani M, Ruggiero RJ, Esserman L, Crawford B. Hormone replacement therapy and breast cancer risk. CANCER PRACTICE 1997; 5:203-8. [PMID: 9250076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Jin B, Turner L, Crawford B, Birrell A, Handelsman DJ. The development of the baboon prostate: ultrasound methodology, modelling, and natural history. JOURNAL OF ANDROLOGY 1996; 17:342-52. [PMID: 8889696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In order to evaluate the potential of ultrasound for serial, nontraumatic estimation of prostate size in the hamadryas baboon (Papio hamadryas), we adapted the technique of planimetric ultrasound to study a captive-bred colony of 30 male baboons (median age 8.4 years, range 3.3-17 years) including 4 long-term castrates. Most (19) were studied on another two occasions (at 33-and 43-day intervals) to estimate reproducibility of the prostate size (dimensions, volume) measurement. Prostatic dimensions were measured with a B-mode sector ultrasound using a 7.5-MHz transrectal transducer by planimetry at 2.5-mm steps from base to apex as well as the maximum three dimensions of the prostate. The planimetric volume estimate was reproducible (intraclass coefficient 0.81) with coefficient of variation (CV) of 24.3% for all, and 16.0% for mature, baboons. The prostate dimensions were also reproducible (CVs 7.9-13.4%). Prostate volume estimates based on the general ellipsoidal model were reasonably reproducible (19.9% for all, 12.9% for mature) but were biased in relationship to the planimetric volume (0.57 +/- 0.19, P = 0.004). Using the independent estimates of prostate volume and dimensions, we developed an empirical power-function model of prostate shape based on the generalized ellipsoidal model that was robust and unbiased (-0.07 +/- 0.15, P = 0.64) with respect to the planimetric volume. This model provides a simpler and accurate formula for prostate volume based on its three maximal dimensional measurements. The natural history of prostate growth in the hamadryas baboon was illustrated by sigmoidal correlations with age (ED50 = 6.0 years, plateau ED95 = 8.3 years), body weight (ED50 = 14.6 kg, ED96 = 16.1 kg), and testis volume (ED50 = 7.8 ml, ED95 = 18.4 ml). Between-animal variability among mature baboons was greater for prostate weight (27%) than body weight (10%), raising the possibility that a subgroup of these baboons may develop spontaneous age-related prostatic hyperplasia. These findings suggest that ultrasonic evaluation of prostate size in the hamadryas baboon may constitute a suitable model for spontaneous benign prostatic hyperplasia and for experimental studies of prostate growth, development, and hormonal regulation.
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Giangola G, Migaly J, Crawford B, Moskowitz P, Sebenick M. Leiomyosarcoma of the subclavian artery. J Vasc Surg 1995; 22:496-500. [PMID: 7563412 DOI: 10.1016/s0741-5214(95)70020-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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