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201.
202.
Alastair van Heerden Shane Norris Stephen Tollman Linda Richter Mary Jane Rotheram-Borus 《Journal of medical Internet research》2013,15(6)
Background
Most of the world’s women living with human immunodeficiency virus (HIV) reside in sub-Saharan Africa. Although efforts to reduce mother-to-child transmission are underway, obtaining complete and accurate data from rural clinical sites to track progress presents a major challenge.Objective
To describe the acceptability and feasibility of mobile phones as a tool for clinic-based face-to-face data collection with pregnant women living with HIV in South Africa.Methods
As part of a larger clinic-based trial, 16 interviewers were trained to conduct mobile phone–assisted personal interviews (MPAPI). These interviewers (participant group 1) completed the same short questionnaire based on items from the Technology Acceptance Model at 3 different time points. Questions were asked before training, after training, and 3 months after deployment to clinic facilities. In addition, before the start of the primary intervention trial in which this substudy was undertaken, 12 mothers living with HIV (MLH) took part in a focus group discussion exploring the acceptability of MPAPI (participant group 2). Finally, a sample of MLH (n=512) enrolled in the primary trial were asked to assess their experience of being interviewed by MPAPI (participant group 3).Results
Acceptability of the method was found to be high among the 16 interviewers in group 1. Perceived usefulness was reported to be slightly higher than perceived ease of use across the 3 time points. After 3 months of field use, interviewer perceptions of both perceived ease of use and perceived usefulness were found to be higher than before training. The feasibility of conducting MPAPI interviews in this setting was found to be high. Network coverage was available in all clinics and hardware, software, cost, and secure transmission to the data center presented no significant challenges over the 21-month period. For the 12 MHL participants in group 2, anxiety about the multimedia capabilities of the phone was evident. Their concern centered on the possibility that their privacy may be invaded by interviewers using the mobile phone camera to photograph them. For participants in group 3, having the interviewer sit beside vs across from the interviewee during the MPAPI interview was received positively by 94.7% of MHL. Privacy (6.3%) and confidentiality (5.3%) concerns were low for group 3 MHL.Conclusions
Mobile phones were found both to be acceptable and feasible in the collection of maternal and child health data from women living with HIV in South Africa.Trial Registration
Clinicaltrials.gov ; http://clinicaltrials.gov/ct2/show/ NCT00972699 (Archived by WebCite at http://clinicaltrials.gov/ct2/show/ NCT00972699) NCT00972699相似文献203.
204.
205.
The minimum important difference for the International consultation on incontinence questionnaire—Urinary incontinence short form in women with stress urinary incontinence
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206.
Linda?BrubakerEmail author Heather?J.?Litman Hae-Young?Kim Philippe?Zimmern Keisha?Dyer John?W.?Kusek Holly?E.?Richter Anne?Stoddard for the Urinary Incontinence Treatment Network 《International urogynecology journal》2015,26(8):1155-1159
Introduction and hypothesis
Missing data is frequently observed in clinical trials; high rates of missing data may jeopardize trial outcome validity.Purpose
We determined the rates of missing data over time, by type of data collected and compared demographic and clinical factors associated with missing data among women who participated in two large randomized clinical trials of surgery for stress urinary incontinence, the Stress Incontinence Surgical Treatment Efficacy Trial (SISTEr) and the Trial of Midurethral Sling (TOMUS).Methods
The proportions of subjects who attended and missed each follow-up visit were calculated. The chi-squared test, Fisher’s exact test and t test were used to compare women with and without missing data, as well as the completeness of the data for each component of the composite primary outcome.Results
Data completeness for the primary outcome computation in the TOMUS trial (62.3 %) was nearly double that in the SISTEr trial (35.7 %). The follow-up visit attendance rate decreased over time. A higher proportion of subjects attended all follow-up visits in the TOMUS trial and overall there were fewer missing data for the period that included the primary outcome assessment at 12 months. The highest levels of complete data for the composite outcome variables were for the symptoms questionnaire (SISTEr 100 %, TOMUS 99.8 %) and the urinary stress test (SISTEr 96.1 %, TOMUS 96.7 %). In both studies, the pad test was associated with the lowest levels of complete data (SISTEr 85.1 %, TOMUS 88.3 %) and approximately one in ten subjects had incomplete voiding diaries at the time of primary outcome assessment. Generally, in both studies, a higher proportion of younger subjects had missing data. This analysis lacked a patient perspective as to the reasons for missing data that could have provided additional information on subject burden, motivations for adherence and study design. In addition, we were unable to compare the effects of the different primary outcome assessment time-points in an identically designed trial.Conclusions
Missing visits and data increased with time. Questionnaire data and physical outcome data (urinary stress test) that could be assessed during a visit were least prone to missing data, whereas data for variables that required subject effort while away from the research team (pad test, voiding diary) were more likely to be missing. Older subjects were more likely to provide complete data.207.
Gutjahr GH van Rensburg LJ Malpaux B Richter TA Bennett NC 《Journal of pineal research》2004,37(3):185-192
Abstract: The day- and night-time levels of plasma melatonin were measured in adult male and female highveld mole-rats, Cryptomys hottentotus pretoriae . This study aimed to assess whether melatonin secretion in this nocturnal, strictly subterranean but seasonally breeding rodent has a day-night rhythm and whether that rhythm is circadian and can be modified by photoperiod. In experiment 1, a day-night rhythm of plasma melatonin was found in all animals housed on a 12L:12D schedule, with significantly higher concentrations in the dark (D) compared with the light (L) phase. The increment of plasma melatonin concentration at night was the same on days 1 and 2 for animals in the control group and animals transferred to constant dark. The animals transferred to constant light substantially reduced the amplitude of the melatonin rhythm on day 2. This suggests that the endogenous melatonin rhythm in C. h. pretoriae has a circadian pattern, which can be synchronized by photoperiod and inhibited by exposure to light at night. In experiment 2, the concentration of plasma melatonin in animals kept under 14L:10D (long day, LD) conditions differed significantly from animals on 10L:14D (short day, SD). This finding supports the notion that C. h. pretoriae is sensitive to changes in day length. 相似文献
208.
Ziegler S Niessner A Richter B Wirth S Billensteiner E Woloszczuk W Slany J Geyer G 《Metabolism: clinical and experimental》2005,54(7):935-938
Abstract The balance of the 2 cytokines, osteoprotegerin (OPG) and the receptor activator of nuclear factor kappa B ligand (soluble (s)RANKL), is known to have considerable influence on bone formation and degradation. Plasma concentrations of OPG and (s)RANKL were determined in a total of 31 long-distance runners before and immediately after running distances of either 15 or 42.195 km, respectively. In both groups of endurance runners, a significant decrease of sRANKL was observed during the run, the extent of which correlated to the running distance. Furthermore, OPG increased only in runners covering the marathon distance of 42.195 km. We hypothesize that the known positive effect of long-distance running on the skeletal mass may be mediated by the OPG/sRANKL system. 相似文献
209.
210.
Dose reduction of inhaled corticosteroids under concomitant medication with montelukast in patients with asthma. 总被引:2,自引:0,他引:2
F Kanniess K Richter S Janicki M B Schleiss R A J?rres H Magnussen 《The European respiratory journal》2002,20(5):1080-1087
The present study aimed at comparing the effects of a dose reduction of inhaled corticosteroids on lung function, indirect measures of airway inflammation and clinical scores during treatment with a leucotriene receptor antagonist. In 50 patients (mean forced expiratory volume in one second (FEV1) 94% predicted), steroid doses (800 microg beclomethasone dipropionate) were first reduced to 50% and then to 25%, for 6 weeks each. One group received a placebo and the other group received montelukast (10 mg). The first reduction did not cause significant effects. During the second, FEV1 and peak expiratory flow decreased in both groups (p<0.001). Daytime symptoms were not altered with placebo but were reduced by montelukast (p<0.05). Night-time symptoms were slightly elevated with placebo (p<0.05) but not montelukast, as well as the use of supplemental salbutamol. Changes in provocative concentration of methacholine causing a 20% fall in FEV1 (PC20), sputum eosinophils and exhaled nitric oxide were mostly nonsignificant for both placebo and montelukast. These data demonstrate that a 75% reduction in the dose of steroid given to patients with asthma led to a deterioration in lung function not prevented by montelukast, whereas changes in clinical state seemed to favour montelukast treatment. It therefore appears that potential effects of montelukast, in the presence of low-dose steroids, could not be attributed to single indices of lung function or airway inflammation. 相似文献