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91.
BackgroundThis analysis was conducted to identify the participant characteristics associated with noncompliance in an oral contraceptive (OC) clinical trial.Study DesignWe studied ovarian suppression among normal-weight and obese women during the use of levonorgestrel (LNG)-containing combination OCs. Participants underwent twice weekly phlebotomy during the study cycle and received up to $360 for participation. Along with other study assays, we analyzed 903 specimens from 181 women to measure LNG to assess OC compliance. Consistently undetectable LNG levels indicated noncompliance. To evaluate predictors of OC noncompliance during this study, we compared the characteristics of compliant and noncompliant participants using multivariable logistic regression. We assigned each participant to a relative poverty level based on US census data; all other individual characteristics came directly from participant responses during the baseline interview.ResultsOne hundred eighty-one women completed the study; 31 were noncompliant (17%). In multivariable analyses, poverty level was the strongest predictor of noncompliance. Compared with those women in the quartile with the lowest level of residential poverty, other women were far more likely to be noncompliant, especially women in the quartile with the greatest prevalence of poverty (adjusted odds ratio, 8.4; 95% confidence interval, 1.5–46.1). Additional factors associated with noncompliance were education level less than a bachelor's degree and Hispanic ethnicity. Other demographic and psychometric measures were not associated with compliance.ConclusionsWe found that noncompliance was strongly associated with residential poverty level, an indirect measure of individual income. In the United States, poverty is associated with female obesity, Hispanic ethnicity and low education, which were also associated here with noncompliance. Study compensation may motivate poor individuals to participate in clinical trials for income. Noncompliance in clinical trials, particularly differential noncompliance, jeopardizes study validity. 相似文献
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Short-term quality of life following abortion is poorly characterized. We conducted a prospective cohort study to evaluate 97 U.S. women who selected either medical abortion with mifepristone and misoprostol or surgical abortion up to 9 weeks gestation in a private-practice setting. Women choosing medical abortion and those choosing surgical abortion with local anesthesia were similar on most baseline characteristics. Eighty-five participants completed a standardized quality of life assessments three times over 1 month. The 30-item questionnaire yielded scores for global health, emotional, social, cognitive and physical functioning and for specific symptom scales. At baseline, participants reported many symptoms and functional limitations during the previous week. Subjects in both treatment groups experienced clinically and statistically significant improvements on all scales at follow-up. Surgical abortion patients had worse scores on three of five function scales and several symptom scales at baseline compared to medical abortion patients. Differences in baseline scores between the medical and surgical abortion patients disappeared during follow-up. A surprising finding was that partner knowledge of the pregnancy at the time the abortion appointment was made was associated with significantly worse scores on most of the function and symptom scales. These results provide substantial reassurance that women undergoing abortion experience a marked improvement in their quality of life after the abortion. Women choosing medical or surgical abortion report very similar quality of life improvements. 相似文献
93.
BACKGROUND: Women often stop hormonal contraception because of perceived weight change. We conducted a randomized trial comparing the contraceptive vaginal ring to a low-dose oral contraceptive (OC). We examined the difference between women's reported and measured baseline weights and looked at factors affecting perceived weight change. METHODS: We randomized 201 participants to either the vaginal ring or an OC for three cycles. We weighed participants upon enrollment (n=194) and at exit (n=167), using the same instrument for all measurements. Participants also provided self-reported height and their reactions to perceived weight changes. RESULTS: Baseline weight and body mass index were similar for both groups (mean weight=145.9 lb). Measured weight was, on average, 4.4 lb more than reported weight; this difference was greater in overweight and obese participants. Participants gained an average of 2.8 lb over 3 months; this gain did not differ between groups or by baseline weight. Subjects who reported a "bad change" in weight at exit (n=34) gained an average of 4.4 lb, whereas those who reported "no change" (n=112) gained 2.2 lb and those who reported a "good change" (n=14) gained 3.3 lb. CONCLUSION: Participants underreported their weight, and this difference was greater for heavier women. There was little weight change for the women in our study. Participants' opinions about weight change were not correlated with measured weight changes. 相似文献
94.
Background
Whole body vibration (WBV) exposure at work is common and studies found evidence that this exposure might cause low back pain (LBP). A recent review concluded there is a lack of evidence of effective strategies to reduce WBV exposure. Most research in this field is focussed on the technical implications, although changing behaviour towards WBV exposure might be promising as well. Therefore, we developed an intervention programme to reduce WBV exposure in a population of drivers with the emphasis on a change in behaviour of driver and employer. The hypothesis is that an effective reduction in WBV exposure, in time, will lead to a reduction in LBP as WBV exposure is a proxy for an increased risk of LBP. 相似文献95.
Efficacy and tolerability of pantoprazole 40 mg versus 80 mg in patients with reflux oesophagitis. 总被引:2,自引:2,他引:2
van Rensburg CJ Honiball PJ Grundling HD van Zyl JH Spies SK Eloff FP Simjee AE Segal I Botha JF Cariem AK Marks IN Theron I Bethke TD 《Alimentary pharmacology & therapeutics》1996,10(3):397-401
BACKGROUND: Pantoprazole is a substituted benzimidazole which is a potent inhibitor of gastric acid secretion by its action upon H+, K+- ATPase. METHODS: Pantoprazole 40 mg and 80 mg were compared in a randomized double-blind study in 192 out-patients with stage II or III (Savary-Miller classification) reflux oesophagitis. Patients received either pantoprazole 40 mg (n = 97) or pantoprazole 80 mg (n = 95), once daily before breakfast for 4 weeks. Treatment was extended for a further 4 weeks if the oesophagitis had not healed. RESULTS: After 4 weeks complete healing of the reflux oesophagitis was seen in 78% of protocol-correct patients given pantoprazole 40 mg daily (n = 86), and in 72% in the 80 mg (n = 87) group. The cumulative healing rates after 8 weeks were 95 and 94%, respectively (P > 0.05, Cochran-Mantel- Haenszel), and time until healing of oesophagitis comparable in both groups. Differences between doses were also not significant in an intention-to-treat analysis. Both dosing schedules were well tolerated and the patients experienced remarkable symptom relief. No adverse event or changes in laboratory values of clinical significance could definitely be ascribed to the trial medication. CONCLUSION: The 40 mg pantoprazole dosage is comparable to 80 mg in reflux oesophagitis, both in efficacy and tolerability. 相似文献
96.
In the Orient there is a high frequency of residual intrahepatic stones after biliary tract surgery. Percutaneous removal of residual intrahepatic stones was attempted in a group of 74 patients. Stones were exclusively intrahepatic in 57 patients, whereas 17 patients also had stones in the common bile duct. Biliary strictures were present in 60 cases (81%). A combination of techniques was used, including preshaped angulated catheters, irrigation-suction, balloon dilation of strictures, and crushing of large stones. In 36 cases all stones were removed and in 14 cases most stones were removed, for a success rate of 67.6%. Biliary stricture was the factor most often responsible for failure. 相似文献
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JH Burridge DE Wood HJ Hermens GE Voerman GR Johnson F. Van Wijck T. Platz M. Gregoric R. Hitchcock AD Pandyan 《Disability and rehabilitation》2005,27(1):69-80
Purpose: To discuss the measurement of spasticity in the clinical and research environments, make recommendations based on the SPASM reviews of biomechanical, neurophysiological and clinical methods of measuring spasticity and indicate future developments of measurement tools. Method: Using the results of the systematic reviews of the biomechanical, neurophysiological and clinical approaches, methods were evaluated across three dimensions: (1) validity, reliability and sensitivity to change; (2) practical quality such as ease of use and (3) qualities specific to the measurement of spasticity, for example ability to be applied to different muscle groups. Methods were considered in terms of applicability to research and clinical applications. Results: A hierarchy of measurement approaches was identified from highly controlled and more objective (but unrelated to function) to ecologically valid, but less objective and subject to contamination from other variables. The lack of a precise definition of spasticity may account for the problem of developing a valid, reliable and sensitive method of measurement. The reviews have identified that some tests measure spasticity per se, some phenomena associated with spasticity or consequential to it and others the effect of spasticity on activity and participation and independence. Conclusions: Methods appropriate for use in research, particularly into the mechanism of spasticity did not satisfy the needs of the clinician and the need for an objective but clinically applicable tool was identified. A clinical assessment may need to generate more than one 'value' and should include evaluation of other components of the upper motor neurone syndrome. There is therefore a need for standardized protocols for 'best practice' in application of spasticity measurement tools and scales. 相似文献