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Estimated Proportion (estimated + proportion)
Selected AbstractsImplementation of the ,Fresh Start' smoking cessation programme to 23 antenatal clinics: a randomized controlled trial investigating two methods of disseminationDRUG AND ALCOHOL REVIEW, Issue 1 2001MARGARET COOKE Abstract The aim of the research was to investigate the effect of two methods of dissemination on the implementation of a smoking cessation programme and use of smoking cessation interventions in antenatal clinics. A repeated-measures randomized design was used. Hospital antenatal clinics (n = 23) were randomized to simple or intensive dissemination groups. All clinics in NSW with > 500 births were asked to participate. A survey of all clinical staff (n = 323) in 23 antenatal clinics was carried out prior to programme dissemination and 18 months after dissemination (n = 283). The response rate was 63% at baseline and 64% at follow-up. Smoking cessation intervention significantly increased after dissemination. (F (18,1) = 49.26, p < 0.001). The average number of smoking cessation interventions provided by clinics after programme dissemination increased from 4.5 to 7. 48 (mean difference 2.98, t(19) 7.08, n < 0.001, 95% CI (2.1,3.86). Type of dissemination did not influence the number of programme components used or the number of smoking cessation interventions offered. Also, the estimated proportion of clients offered intervention by clinicians did not vary due to type of dissemination. A simple mail-out of a smoking cessation programme to antenatal clinics for use during pregnancy can increase clinician intervention for smoking. When more intensive methods of dissemination are used, the quality of the interventions implemented by clinicians improves. More research on dissemination methods are required as both methods of dissemination did not produce systematic or sustained use of the programme. [source] Carry-over effects in a Pacific seabird: stable isotope evidence that pre-breeding diet quality influences reproductive successJOURNAL OF ANIMAL ECOLOGY, Issue 2 2009Marjorie C. Sorensen Summary 1Understanding the interactions between different periods of the annual cycle in migratory animals has been constrained by our inability to track individuals across seasons. In seabirds, virtually nothing is known about how diet quality during the non-breeding period, away from the breeding grounds, might influence subsequent reproductive success. 2We used stable nitrogen (,15N) and carbon (,13C) isotopes to evaluate the effects of non-breeding diet quality on the timing of breeding and egg size in a population of Cassin's auklets (Ptychoramphus aleuticus) breeding on Triangle Island, British Columbia. Adult feathers are grown during two different periods of the annual cycle, which allowed us to estimate diet quality from the previous fall (October,November) and pre-breeding (February,March) period. 3We found that the estimated proportion of energetically superior copepods (Neocalanus spp.) in the pre-breeding diet tended to be higher in females that bred earlier and laid larger eggs, whereas energetically poor juvenile rockfish (Sebastes spp.) were dominant in the pre-breeding diets of females that bred later and laid smaller eggs. We detected no effect of fall diet quality on breeding date or egg size, and no effect of pre-breeding diet quality on breeding date in males. 4Pre-breeding diet quality was not related to body condition measured 1,2 days after laying, which suggests that females may need to attain a threshold condition before they initiate breeding and successfully rear young. 5Our results suggest that changes in climatic conditions during the pre-breeding period may have severe consequences for reproductive success by influencing breeding date and egg size. Our work emphasizes the importance of determining how events are linked throughout the annual cycle for understanding the fitness and population dynamics of migratory animals. [source] Diet reconstruction and historic population dynamics in a threatened seabirdJOURNAL OF APPLIED ECOLOGY, Issue 4 2007D. RYAN NORRIS Summary 1For the overwhelming majority of species, we lack long-term information on the dynamics of populations. As a consequence, we face considerable uncertainty about how to discriminate among competing hypotheses of population decline and design conservation plans. 2The marbled murrelet Brachyramphus marmoratus is a small seabird that nests in coastal old-growth forest but feeds year-round in near-shore waters of the north-eastern Pacific. Although a decline in nesting habitat is the primary reason why marbled murrelets are listed as threatened in Canada, nest predation and food availability may also influence population abundance. To examine the hypothesis that murrelet populations are influenced by variation in diet quality, we analysed stable-carbon and -nitrogen isotopes in feathers of museum specimens collected in the Georgia Basin, British Columbia. 3Between 1889 and 1996, we found a decline in stable isotopic signatures that was approximately equal to a 62% drop in trophic feeding level. We also found that the estimated proportion of fish in murrelet diet was related closely to murrelet abundance over the past 40 years, as estimated from volunteer surveys. Using these isotopic data, we modelled population size as a function of variation in reproductive rate due to changes in diet quality and found that our model matched closely the 40-year field estimates. We then applied our 107-year isotopic record to the model to back-cast estimates of population growth rate to 1889. 4Our results suggest that, up to the 1950s, murrelet populations in the Georgia Basin were capable of growing and were probably limited by factors other than diet quality. After this period, however, our results imply that murrelets were often, but not solely, limited by diet quality. 5Synthesis and applications. Protecting nesting habitat may not be sufficient to rebuild populations of this highly secretive and threatened seabird and recovery might also require the restoration of marine habitat quality, as well as a better understanding of how ocean climate affects prey abundance and reproductive rate. Combined with contemporary demographic data, stable isotope analysis of historic samples provides a unique opportunity to reconstruct population histories for species where we lack long-term information. [source] Update on the Epidemiology of Paget's Disease of BoneJOURNAL OF BONE AND MINERAL RESEARCH, Issue S2 2006Cyrus Cooper Abstract Paget's disease of bone (PDB) is characterized by rapid bone remodeling and the formation of bone that is structurally abnormal. Recent studies have confirmed that both genetic and environmental factors are important in its etiology. Epidemiological studies in Europe and North America have revealed that PDB shows an increasing frequency of occurrence with age and is more prevalent among men than women. There is marked geographic variation in the prevalence of PDB throughout western nations, with the highest rates reported during the 1970s in Britain. Recent studies of the secular trends in PDB suggest declining rates in both prevalence and severity at diagnosis. Thus, the overall age/sex standardized prevalence rate in Britain during the period 1993,1995 was found to be 2.5% among men and 1.6% among women ,55 years of age. Prevalence rates had fallen by ,50% in several of the centers studied, suggesting an environmental contribution to the etiology of this disorder. Similar findings have been reported from other European countries and New Zealand. Recent study of the incidence and clinical manifestations of PDB have emerged from large cohort studies in primary care record linkage resources, such as the General Practice Research Database. Over the period 1988,1999, the incidence rate of clinically diagnosed PDB was found to be 5 per 10,000 person-years among men and 3 per 10,000 person-years among women 75 years of age. The disorder was associated with an increased risk of back pain (RR, 2.1; 95% CI, 1.9,2.3); osteoarthritis (RR, 1.7; 95% CI, 1.5,1.9); and fracture (RR, 1.2; 95% CI, 1.0,1.5). Using life table methodology, the estimated proportion of patients dying within 5 years of follow-up was 32.7% among the cohort with PDB compared with 28.0% among control patients (p < 0.05). [source] Safety of the Canadian blood supply in 1980,85: using a paediatric cohort for risk assessment of human immunodeficiency virus (HIV) infectionPAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 1 2001King The risk of HIV from transfusions in Canada in the period 1980,85 was estimated, using the information from a transfused paediatric cohort. Children who were transfused between January 1980 and November 1985 at a tertiary care paediatric hospital were contacted by letter. With this notification, HIV testing for recipients was recommended. HIV testing histories were obtained. The number tested for HIV was estimated from the questionnaire responses and from data matching with the HIV-testing laboratory. Cases of HIV infection were identified through multiple sources. In this cohort, 11 028 children were transfused a mean of 21 units. Of the 10 220 living recipients, the estimated proportion tested for HIV was 86% to 91%. Thirty-one cases of HIV infection were identified, representing 0.28% of the cohort but 0.34% of those expected to have been tested. The estimated HIV incidence per 1000 units transfused ranged from 0.028 [95% CI 0.0007, 0.155] in 1980 to 0.445 [95% CI 0.2592, 0.712] in 1985. This suggests that the risk of HIV from transfusions in Canada continued to rise until the implementation of HIV testing of donors in November 1985. [source] | |||||||||||||