Test Treatment (test + treatment)

Distribution by Scientific Domains


Selected Abstracts


Professional Errors Caused by Lasers and Intense Pulsed Light Technology in Dermatology and Aesthetic Medicine: Preventive Strategies and Case Studies

DERMATOLOGIC SURGERY, Issue 2 2002
Baerbel Greve MD
background. The use of lasers and intense pulsed light (IPL) technology has become established practice in dermatology and aesthetic medicine. The increase in popularity and widespread use of such equipment has been accompanied by a sharp increase in the number of case reports about professional errors. objective. We present 14 case studies of professional errors. methods. Selected representative case reports are used to illustrate and discuss typical professional errors and serve as the basis for creating preventive strategies. results. Recommendations have been developed for the following areas: physician training, patient information, documentation, diagnosis, indication, test treatment, and performing treatment. conclusion. The use of lasers and IPL technology in dermatology and aesthetic medicine requires practitioners not only to have high levels of training and experience, but also to exercise professional judgment. In spite of all of the precautions taken, the risk of complications and side effects can be reduced but not completely eliminated. [source]


Adjunctive benefits of systemic amoxicillin and metronidazole in non-surgical treatment of generalized aggressive periodontitis: a randomized placebo-controlled clinical trial

JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 10 2005
Adrian Guerrero
Abstract Background: The objective of this study was to assess the adjunctive clinical effect of the administration of systemic amoxicillin and metronidazole in the non-surgical treatment of generalized aggressive periodontitis (GAP). Methods: Forty-one systemically healthy subjects with GAP were included in this 6-month double-blind, placebo-controlled, randomized clinical trial. Patients received a course of full-mouth non-surgical periodontal treatment delivered over a 24 h period using machine-driven and hand instruments. Test subjects received an adjunctive course of systemic antibiotic consisting of 500 mg amoxicillin and 500 mg metronidazole three times a day for 7 days. Clinical parameters were collected at baseline, and at 2 and 6 months post-treatment. Results: In both the test and the placebo groups, all clinical parameters improved at 2 and 6 months. In deep pockets (7 mm), the test treatment resulted in an additional 1.4 mm (95% confidence interval 0.8, 2.0 mm) in full-mouth probing pocket depth (PPD) reduction and 1 mm (0.7, 1.3 mm) of life cumulative attachment loss (LCAL) gain at 6 months. In moderate pockets (4,6 mm), the adjunctive benefit was smaller in magnitude: PPD reduction was 0.4 mm (0.1, 0.7 mm) and LCAL gain was 0.5 mm (0.2, 0.8 mm). In addition, the 6-month data showed LCAL gains 2 mm at 25% of sites in test patients compared with 16% in placebo (p=0.028). Similarly, PPD reductions of 2 mm or more were observed in 30% of sites in test and 21% of sites in placebo patients. Seventy-four percent of pockets with PPD 5 mm at baseline were 4 mm or shallower at 6 months in the test group. This compared with 54% in the placebo group (p=0.008). Disease progression at 6 months was observed at 1.5% of test and 3.3% of sites in test and placebo, respectively (p=0.072). Conclusions: These data indicate that a 7-day adjunctive course of systemic metronidazole and amoxicillin significantly improved the short-term clinical outcomes of full-mouth non-surgical periodontal debridement in subjects with GAP. [source]


Challenges and regulatory experiences with non-inferiority trial design without placebo arm

BIOMETRICAL JOURNAL, Issue 2 2009
H. M. James Hung
Abstract For a non-inferiority trial without a placebo arm, the direct comparison between the test treatment and the selected positive control is in principle the only basis for statistical inference. Therefore, evaluating the test treatment relative to the non-existent placebo presents extreme challenges and requires some kind of bridging from the past to the present with no current placebo data. For such inference based partly on an indirect bridging manipulation, fixed margin method and synthesis method are the two widely discussed methods in the recent literature. There are major differences in statistical inference paradigm between the two methods. The fixed margin method employs the historical data that assess the performances of the active control versus a placebo to guide the selection of the non-inferiority margin. Such guidance is not part of the ultimate statistical inference in the non-inferiority trial. In contrast, the synthesis method connects the historical data to the non-inferiority trial data for making broader inferences relating the test treatment to the non-existent current placebo. On the other hand, the type I error rate associated with the direct comparison between the test treatment and the active control cannot shed any light on the appropriateness of the indirect inference for faring the test treatment against the non-existent placebo. This work explores an approach for assessing the impact of potential bias due to violation of a key statistical assumption to guide determination of the non-inferiority margin. [source]


Applications of Extensions of Bivariate Rank Sum Statistics to the Crossover Design to Compare Two Treatments Through Four Sequence Groups

BIOMETRICS, Issue 3 2009
Atsushi Kawaguchi
Summary This article describes applications of extensions of bivariate rank sum statistics to the crossover design with four sequence groups for two treatments. A randomized clinical trial in ophthalmology provides motivating background for the discussion. The bilateral design for this study has four sequence groups T:T, T:P, P:T, and P:P, respectively, for T as test treatment or P as placebo in the corresponding order for the left and right eyes. This article describes how to use the average of the separate Wilcoxon rank sum statistics for the left and right eyes for the overall comparison between T and P with the correlation between the two eyes taken into account. An extension of this criterion with better sensitivity to potential differences between T and P through reduction of the applicable variance has discussion in terms of a conceptual model with constraints for within-side homogeneity of groups with the same treatment and between-side homogeneity of the differences between T and P. Goodness of fit for this model can have assessment with test statistics for its corresponding constraints. Simulation studies for the conceptual model confirm better power for the extended test statistic with its full invocation than other criteria without this property. The methods summarized here are illustrated for the motivating clinical trial in ophthalmology, but they are applicable to other situations with the crossover design with four sequence groups for either two locations for two treatments at the same time for a patient or two successive periods for the assigned treatments for a recurrent disorder. This article also notes that the methods based on its conceptual model can have unsatisfactory power for departures from that model where the difference between T and P via the T:T and P:P groups is not similar to that via the T:P and P:T groups, as might occur when T has a systemic effect in a bilateral trial. For this situation, more robust test statistics have identification, but there is recognition that the parallel groups design with only the T:T and P:P groups may be more useful than the bilateral design with four sequence groups. [source]


An evaluation of bovine derived xenograft with and without a bioabsorbable collagen membrane in the treatment of mandibular Class II furcation defects

AUSTRALIAN DENTAL JOURNAL, Issue 3 2009
M Taheri
Abstract Background:, The aim of this study was to compare the clinical outcomes of applying Bio-Oss®, an anorganic bovine bone xenograft (control group) to the combined use of Bio-Oss® and Bio-Gide® (a bioabsorbable collagen membrane) (test group) in human mandibular Class II furcation defects. Methods:, A total of 18 furcations (8 tests and 10 controls) in 14 patients suffering from chronic periodontitis were treated in this randomized clinical trial. Open vertical and horizontal furcation depths (OVFD and OHFD), vertical and horizontal clinical attachment levels (VCAL, HCAL), probing depth (PD) and free gingival marginal level (GML) were among the clinical parameters measured prior and six months after treatment, at re-entry surgery. The data were analysed by statistical tests while a p value less than 0.05 was considered significant. Results:, At the surgical re-entry, the mean reduction for OVFD of the control and test groups was 1.9 ± 1.3 and 2.1 ± 1.0, and for OHFD 2.1 ± 0.7 and 2.4 ± 1.3, respectively. The control and test treatments resulted in significant reductions in PD, VCAL and HCAL measurements at re-entry but there was no statistically significant difference between the two treatments in all soft and hard tissues measurements. Conclusions:, This clinical trial failed to demonstrate the superiority of the combined use of Bio-Gide® and Bio-Oss® to the use of Bio-Oss® alone, although both therapies resulted in significant gains in attachment level and bone fill. [source]