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Robitaille A.,University of Victoria | Orpana H.,University of Ottawa | McIntosh C.N.,Statistical Consultants Ltd
Canadian Journal on Aging | Year: 2012

In this study we examined the longitudinal relationships between five dimensions of social support and psychological distress to determine whether (1) social support was related to subsequent psychological distress levels; or (2) if distress levels were related to subsequent social support levels; or (3) if distress and support had a reciprocal (bi-directional) relationship across time. Using bivariate autoregressive cross-lagged models, we analysed data from 2,564 older adults. We found support for the reciprocal relationship between affectionate support and distress. Higher psychological distress was related to subsequently higher levels of positive social interaction, and significantly related to subsequently higher emotional/informational support. No significant relationship was found between tangible and structural support and psychological distress. This study demonstrates that different types of support are associated in correspondingly different ways with psychological distress, and that psychological distress may be important in predicting levels of social support two years later. © 2012 Canadian Association on Gerontology.


Kadam R.V.,Statistical Consultants Ltd | Field J.B.,University of Adelaide
Journal of Anaesthesiology Clinical Pharmacology | Year: 2011

Introduction: Transversus abdominis plane (TAP) block is a new regional analgesic technique for postoperative pain in abdominal surgery. Its efficacy is not clear, and thus it needs to be explored for its regular utilisation on prolonged period. The objective was to study the continuous local anaesthetic infusion effect on postoperative analgesia. Continuous use of TAP block as an analgesic technique has not been evaluated prospectively in clinical trials. This study evaluates the efficacy of ultrasoundguided TAP block in comparison with PCA fentanyl in major abdominal surgery. Materials and Methods: There were 20 patients in the study, allocated to TAP and control groups. The parameters measured were pain scores on a numerical rating scale (NRS) of 0-10 at various time intervals and the amount of fentanyl used as rescue analgesia. Patient satisfaction scores were recorded in the TAP block group and along with any complications related to the block. Results: The postoperative median pain scores on coughing on day one were 6.0 for control group and 2.0 for the TAP group (P = 0.02); on day two, the equivalent scores were 7.0 and 2.0 (P = 0.01). The fentanyl requirement at one hour was 203 μ for the control group and 78 μg for the TAP group (P = 0.03); at day one, the control and TAP requirements were 1237 μg and 664 μg respectively (P = 0.01). Three TAP patients rated their satisfaction as 'excellent', four as 'satisfied, and two as 'poor'. Conclusion: TAP block is a promising technique for postoperative analgesia in major abdominal surgeries. Our study demonstrated lower pain scores in the TAP group with reduced fentanyl requirement. Further, a large scale study is needed to establish the efficacy of TAP block in this setting.


Schuster M.G.,University of Pennsylvania | Meibohm A.,Statistical Consultants Ltd | Lloyd L.,Philadelphia Medical Center | Strom B.,University of Pennsylvania
Journal of Infection | Year: 2013

To investigate the risk factors and outcomes associated with Candida krusei bloodstream. Methods: We performed a case control study of patients with C. krusei bloodstream infection at the University of Pennsylvania from 1982 to 2010. Controls were without candidemia, and matched to cases on duration of hospitalization and underlying disease. Results: We enrolled 34 cases and 114 matched controls. Most subjects (62%) had hematologic malignancies. In the multivariate model, including a priori the duration of fluconazole use (OR 1.06; 95% CI 1.00, 1.11) and days of neutropenia (OR 1.01; 95% CI 0.98, 1.13), risk factors associated with C. krusei bloodstream infection were splenectomy (OR 11.66; 95% CI 1.04, 130.64), and exposure to antimicrobials with anaerobic activity (OR 5.74; 95% CI 1.76, 18.67). Outcomes of infected patients were poor. Only 32% of case patients survived to hospital discharge, compared to 89% of controls. For 48% death was attributed to C. krusei infection. Conclusions: C. krusei bloodstream infection occurs most commonly in neutropenic patients with hematologic malignancy. The association with prior fluconazole exposure is less marked than previously described. Splenectomy and the receipt of antimicrobials with anaerobic activity are significant risk factors. The outcome of infected patients remains poor, despite appropriate antifungal therapy. © 2012.


Mericle A.A.,Treatment Research Institute | Ta Park V.M.,San Jose State University | Holck P.,Statistical Consultants Ltd | Arria A.M.,Treatment Research Institute | Arria A.M.,University of Maryland University College
Comprehensive Psychiatry | Year: 2012

Objective: This study examines racial/ethnic differences in the prevalence, patterns, and correlates of co-occurring substance use and mental disorders (COD) among Whites, Blacks, Latinos, and Asians using data from the Collaborative Psychiatric Epidemiology Studies. Method: We first estimated the prevalence of various combinations of different co-occurring depressive and anxiety disorders among respondents with alcohol, drug, and any substance use (alcohol or drug) disorders in each racial/ethnic group. We then estimated the prevalence of different patterns of onset and different psychosocial correlates among individuals with COD of different racial/ethnic groups. We used weighted linear and logistic regression analysis controlling for key demographics to test the effect of race/ethnicity. Tests of differences between specific racial/ethnic subgroups were only conducted if the overall test of race was significant. Results: Rates of COD varied significantly by race/ethnicity. Approximately 8.2% of Whites, 5.4% of Blacks, 5.8% of Latinos, and 2.1% of Asians met criteria for lifetime COD. Whites were more likely than persons in each of the other groups to have lifetime COD. Irrespective of race/ethnicity, most of those with COD reported that symptoms of mental disorders occurred before symptoms of substance use disorders. Only rates of unemployment and history of psychiatric hospitalization among individuals with COD were found to vary significantly by racial/ethnic group. Conclusions: Our findings underscore the need to further examine the factors underlying differences between minority and nonminority individuals with COD as well as how these differences might affect help seeking and utilization of substance abuse and mental health services. © 2012 Elsevier Inc.


Williamson E.D.,UK Defence Science and Technology Laboratory | Duchars M.G.,Genie Bio Logic Frederick | Kohberger R.,Statistical Consultants Ltd
Expert Review of Vaccines | Year: 2010

The identification of immune correlates of protection is becoming increasingly important in order to derive a quantitative assessment of the benefit conferred by vaccination in clinical trials. The use of immune correlates of protection as an indirect measure of clinical efficacy is essential to achieve regulatory approval for vaccines for which clinical efficacy cannot be tested directly, for example, biodefence vaccines. The correlates apply to the specific vaccine formulation being developed; in general, if a statistically significant correlation is found between a measurable immunological readout and survival in authentic animal models of human infection, the same immunological readout can be defined and applied as a surrogate marker of protection in clinical studies. The surrogate markers of protection can then be used to predict the protective efficacy of a candidate vaccine in humans. This review summarizes some of the immune correlates data reported for biodefence vaccines as well as some of the analytical approaches that can be applied in order to predict clinical efficacy. © 2010 Expert Reviews Ltd.


Sun G.,Celgene | Quan H.,Sanofi S.A. | Kringle R.,Statistical Consultants Ltd | Meng Z.,Sanofi S.A.
Journal of Biopharmaceutical Statistics | Year: 2012

The ICH E14 guidance recommends the use of a time-matched baseline, while others recommend alternative baseline definitions including a day-averaged baseline. In this article we consider six models adjusting for baselines. We derive the explicit covariances and compare their power under various conditions. Simulation results are provided. We conclude that type I error rates are controlled. However, one model outperforms the others on statistical power under certain conditions. In general, the analysis of covariance (ANCOVA) model using a day-averaged baseline is preferred. If the time-matched baseline has to be used as per requests from regulatory agencies, the analysis by time point using ANCOVA model should be recommended. Copyright © Taylor & Francis Group, LLC.


Trottier O.,University of Auckland | Walker D.,Statistical Consultants Ltd | Jeffs A.G.,University of Auckland
Aquaculture | Year: 2012

Pea crabs are a common parasite of bivalves around the world and frequently cause problems for bivalve aquaculture through end-consumer complaints and rejections of consignments at international borders due to biosecurity concerns. However, the financial impact of pea crabs on aquaculture production has never been quantified for any bivalve species. A large scale systematic sampling of a typical green-lipped mussel farm in New Zealand revealed that pea crabs were present in 5.3% (±0.062 SE) of the mussels. The abundance of crabs increased gradually with decreasing water depth beneath the farm and greater distance from the shoreline. Mussels infected with pea crabs were 30% smaller in total wet weight [F1, 2573=669, p=0.00], had a 29% lower meat yield [F1, 2573=355, p=0.00], and shell dimensions were also significantly affected. A total production loss on the 1.71ha farm was estimated at 803kg at harvest. When this measured loss is extrapolated to current total mussel aquaculture production in New Zealand, pea crab infection represents an estimated loss to the industry of US$2.16 million annually. Our results indicate that parasitic pea crabs are producing a significant loss of production in shellfish farming aquaculture operations, even at low levels of infection, and therefore warrant a great deal more attention in terms of developing effective control measures. © 2012 Elsevier B.V..


Miller I.M.,Copenhagen University | Nielsen J.S.,Copenhagen University | Lophaven S.,Statistical Consultants Ltd | Jemec G.B.E.,Copenhagen University
Journal of the European Academy of Dermatology and Venereology | Year: 2011

Background Pain may be a limiting factor in the use of photodynamic therapy (PDT). The consequences of the pain i.e. the resources spent on pain-intervention during routine PDT therapy are poorly described. Objectives To describe the consequences of pain during PDT by describing the use of pain-reducing interventions in routine use. We studied the frequency as well as level of pain-reducing intervention. Methods Descriptive data from PDT treated patients. The level of pain-reducing intervention was graded 0, no intervention; +, cold water spray and ++, pause or nerve block. Results Data from 983 PDT treatments on 579 lesions distributed on 301 patients: 56% did not require pain-reducing intervention, 35% required spraying of cold water, while 9% required pause or nerve block. Ordinate logistic regression revealed an association between lesion size and pain-reducing intervention: the larger the lesion, the more frequent the intervention. Lesion size did not, however, appear associated with the level of intervention. Intervention was most frequently required when treating the scalp/forehead and the extremities. The scalp/forehead also required the highest level of intervention. No significant association between pain-reducing intervention and diagnosis, pre-treatment, gender or age was found. Conclusions Pain-reducing intervention was required in 44% of the PDT treatments. Intervention was particularly required when treating lesions in areas suited for PDT therapy for cosmetic reasons such as the scalp/forehead or extremities. Treatment of large areas more frequently calls for pain intervention than treatment of small areas. © 2011 European Academy of Dermatology and Venereology.


Andrade J.G.,Montreal Heart Institute | Andrade J.G.,University of British Columbia | Khairy P.,Montreal Heart Institute | Macle L.,Montreal Heart Institute | And 5 more authors.
Circulation: Arrhythmia and Electrophysiology | Year: 2014

Background-Early recurrence of atrial fibrillation (ERAF) is common after radiofrequency catheter ablation for AF. We sought to determine the incidence and prognostic significance of ERAF after cryoballoon ablation. Moreover, the benefit of early reablation for ERAF after cryoballoon ablation is undetermined. Methods and Results-The Sustained Treatment of Paroxysmal Atrial Fibrillation (STOP AF) trial randomized 245 patients with paroxysmal AF to medical therapy versus cryoballoon-based pulmonary vein ablation. Patients were followed for 12 months. ERAF was defined as any recurrence of AF >30 seconds during the first 3 months of follow-up. Late recurrence (LR) was defined as any recurrence of AF >30 seconds between 3 and 12 months. Of the 163 patients randomized to cryoablation, 84 patients experienced ERAF (51.5%). The only significant factor associated with ERAF was male sex (hazard ratio [HR], 2.18; 95% confidence interval [CI], 1.03-4.61; P=0.041). LR was observed in 41 patients (25.1%), and was significantly related to ERAF (55.6% LR with ERAF versus 12.7% without ERAF; P<0.001). Among patients with ERAF, only current tobacco use (HR, 3.84; 95% CI, 1.82-8.11; P<0.001) was associated with LR. Conversely, early reablation was associated with greater freedom from LR (3.3% LR with early reablation versus 55.6% without; HR, 0.04; 95% CI, 0.01-0.32; P=0.002). Conclusions-ERAF after cryoballoon ablation occurs in ≈50% of patients and is strongly associated with LR. Early reablation for ERAF is associated with excellent long-term freedom from recurrent AF. © 2013 American Heart Association, Inc.


Onderdijk A.J.,Deventer Hospital | Onderdijk A.J.,Erasmus Medical Center | Van Der Zee H.H.,Erasmus Medical Center | Esmann S.,Copenhagen University | And 4 more authors.
Journal of the European Academy of Dermatology and Venereology | Year: 2013

Background Hidradenitis suppurativa (HS) is a chronic recurrent inflammatory skin disease with abscess formation and scarring predominantly in the inverse areas. The disease is often difficult to treat and patients experience a decreased quality of life (QoL). It is hypothesized that depression is more common in HS patients than among other dermatological patients. Objectives To evaluate the prevalence of depression in patients with HS. Methods In total 211 HS patients were included in the study and 233 were dermatological control patients. Their QoL and depression scores were assessed using the Dermatology Life Quality Index (DLQI) and the Major Depression Inventory (MDI) questionnaires. HS severity was recorded with a questionnaire and Hurley stages were extracted from the case records. Results The DLQI was significantly higher for HS patients than for the control patients, 8.4 ± 7.5 vs. 4.3 ± 5.6 (P < 0.0001) and correlated with Hurley stage severity scores. Mean MDI scores were significantly higher for HS patients, 11.0 vs. 7.2 (P < 0.0001). However, clinically defined depression rates according to the International Classification of Diseases, 10th edition (ICD-10) criteria were not significantly higher in HS patients compared to controls (9% vs. 6%). Conclusions HS is a chronic skin disease with major impact on QoL even when compared to other dermatological diseases. MDI scores in HS patients correlate with disease severity. This correlation could indicate that the MDI represents a valid measure of disease related morbidity that may serve as an outcome measure in future studies and a relevant point of intervention for individual patients. © 2012 The Authors. Journal of the European Academy of Dermatology and Venereology © 2012 European Academy of Dermatology and Venereology.

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