Knowledge Representation for Computer-Aided Planning of Controlled Clinical Trials: the PATriCIa Project

1997 ◽  
Vol 36 (03) ◽  
pp. 172-178 ◽  
Author(s):  
U. Haag
Keyword(s):  
Clinical Trials ◽  
Knowledge Representation ◽  
Formal Representation ◽  
Controlled Clinical Trials ◽  
Knowledge Based ◽  
Study Protocols ◽  
Representation Method ◽  
Computer Aided Planning ◽  
Research Structure

The main thesis of the PATriCIa project is that a knowledge-based system can provide efficient and reliable support for biometricians as well as physicians involved in planning of controlled clinical trials, resulting in a higher quality of medical research. Structure and contents of study protocols are analyzed, and an object-oriented method for formally representing biometric knowledge is proposed. A study protocol can be generated from this formal representation. The programming language Prolog is used to realize the system based on a blackboard architecture. It is concluded that the knowledge representation method developed in the PATriCIa project is well suited for the purpose of generating study protocols for controlled clinical trials.

scholarly journals Methodological Characteristics of Clinical Trials: Impact of Mandatory Trial Registration

2019 ◽  
Vol 22 ◽  
pp. 131-141
Author(s):  
Ashish Kumar Kakkar ◽  
Biswa Mohan Padhy ◽  
Sudhir Chandra Sarangi ◽  
Yogendra Kumar Gupta
Keyword(s):  
Clinical Trial ◽  
Clinical Trials ◽  
Statistical Methods ◽  
Quality Characteristics ◽  
Allocation Concealment ◽  
Trial Registration ◽  
Control Group ◽  
Study Protocols ◽  
The Impact

Purpose: Numerous studies across multiple specialties have evaluated the impact of trial registration on quality of study reports and found significant improvements over several domains. However, the impact of mandatory trial registration on the quality of clinical trial protocols remains hitherto unexplored. Methods: We carried out a retrospective cohort study of clinical trial applications submitted to drug regulatory authority of India for initial review with the objective of comparing methodological characteristics of their protocols. Since trial registration was made mandatory in the country in June 2009, we selected two study periods as between January 2007 to May 2009 (Period I) and July 2009 to December 2011 (Period II). Seventy-five protocols were randomly selected using a computer-generated list for each study period, making a total of 150 protocols. Data on twelve key methodological characteristics were collected including clearly defined primary outcomes, randomization, blinding, use of control group, statistical methods, handling of withdrawals amongst others. Results: More than 3/4th of the trial applications in the two study periods were for new chemical entities and nearly 90% were pharmaceutical industry sponsored studies. Comparing the period before and after implementation of mandatory trial registration, description of clearly defined trial outcomes improved from nearly 42% to 80% (p<0.001), sample size justifications increased from 38% to 70% (p<0.001) and use of allocation concealment improved from 24% to 49% (p=0.001). Marked improvement was also noted for blinding, description of statistical methods and handling of withdrawals and dropouts. Remaining characteristics did not change significantly between the two study periods. The mean cumulative scores for the study protocols improved significantly from 7± 0.296 in the first period to 8.93± 0.346 (p<0.001) in the second period. Conclusions: Our study found a significant improvement in the methodological quality characteristics of the protocols particularly in elements related to minimization of bias and statistical methods, which could be attributed to mandatory trial registration. Overall, the significant improvement was limited to global clinical trials, and room for improvement was noted for two quality characteristics – proportion of randomized studies and trials adequately describing the generation of allocation sequence.

scholarly journals Adherence to the 2008 IHS guidelines for controlled trials of drugs for the preventive treatment of chronic migraine in adults

Cephalalgia ◽  
2019 ◽  
Vol 39 (8) ◽  
pp. 1058-1066 ◽  
Author(s):  
Marie Deen ◽  
Daniele Martinelli ◽  
Judith Pijpers ◽  
Hans-Christoph Diener ◽  
Stephen Silberstein ◽  
...  
Keyword(s):  
Clinical Trials ◽  
Chronic Migraine ◽  
International Headache Society ◽  
A Priori ◽  
Preventive Treatment ◽  
Controlled Clinical Trials ◽  
Trial Quality ◽  
Definition Of ◽  
Double Blinded

Introduction Since the definition of chronic migraine as a new disease entity in 2004, numerous clinical trials have examined the efficacy of preventive treatments in chronic migraine. Our aim was to assess the adherence of these trials to the Guidelines of the International Headache Society published in 2008. Methods We searched PubMed for controlled clinical trials investigating preventive treatment for chronic migraine in adults designed after the release of the Guidelines and published until December 2017. Trial quality was evaluated with a 13-item scoring system enlisting essential recommendations adapted from the Guidelines. Results Out of 3352 retrieved records, we included 16 papers in the analysis dealing with pharmacological treatment of chronic migraine. The median score was 6.5 (range 2–13). All trials were randomized, the large majority (81.25%) were placebo-controlled and double-blinded (87.5%). Adherence was lowest on i) a priori definition of outcomes (31.25%), ii) primary endpoint definition (37.5%%) and iii) trial registration (37.5%). Discussion Most clinical trials adhered to the recommendations of the IHS, whereas adherence to migraine-specific recommendations was lower. Greater awareness and adherence to the guidelines are essential to improve the quality of clinical trials, validity of publications and the generalizability of the results.

Effectiveness and safety of endoscopic thoracic sympathectomy for excessive sweating and facial blushing: A systematic review

2007 ◽  
Vol 23 (1) ◽  
pp. 54-62 ◽  
Author(s):  
Antti Malmivaara ◽  
Pekka Kuukasjärvi ◽  
Ilona Autti-Ramo ◽  
Niina Kovanen ◽  
Marjukka Mäkelä
Keyword(s):  
Systematic Review ◽  
Clinical Trials ◽  
Side Effects ◽  
Quality Data ◽  
Controlled Clinical Trials ◽  
Endoscopic Thoracic Sympathectomy ◽  
Excessive Sweating ◽  
Thoracic Sympathectomy ◽  
Facial Blushing

Objectives:Despite controversies, endoscopic thoracic sympathectomy (ETS) has been used as a treatment for excessive sweating of hands and face and for facial blushing. This study aims to evaluate the effectiveness of ETS for the current indications in a systematic review.Methods:Controlled clinical trials and cohort studies with more than 100 patients were included. Abstracts were searched from MEDLINE and CCTR from 1966 to June 2004. Two reviewers extracted the data and assessed study quality. Data on effectiveness and safety were synthesized qualitatively.Results:We did not find any controlled clinical trials. Fifteen prospective studies were included. The internal and external quality of these studies were poor overall. Follow-up was commonly less than 2 years, during which time excessive sweating and facial blushing seemed to decrease among most patients. Immediate complications related to thoracoscopy occurred in up to 10 percent of patients. Compensatory sweating below breast level was reported in up to 90 percent of the patients. Other common side effects included dryness of face and hands, gustatory sweating, and neuralgic pain. Several other less common side effects were reported.Conclusions:The evidence of the effectiveness of ETS is weak due to a lack of randomized trials. The intervention leads to severe immediate complications in some of the patients, and to persistent side-effects for many of the patients.

Economic Analysis Alongside Clinical Trials: Revisiting the Methodological Issues

1991 ◽  
Vol 7 (4) ◽  
pp. 561-573 ◽  
Author(s):  
Michael F. Drummond ◽  
Linda Davies
Keyword(s):  
Clinical Trials ◽  
Economic Analysis ◽  
Resource Use ◽  
Trial Design ◽  
Outcome Data ◽  
Medical Evidence ◽  
Controlled Clinical Trials ◽  
Methodological Issues ◽  
Health Care Interventions

AbstractControlled clinical trials are recognized as the best source of data on the efficacy of health care interventions and technologies. Because economic evaluation is dependent on the quality of the underlying medical evidence, clinical trials have increasingly been viewed as a natural vehicle for economic analysis. However, the closer integration of economic and clinical research raises many methodological issues. This paper discusses these issues in trial design, collection of resource use data, collection of outcome data, and interpretation and extrapolation of results. Some guidelines are suggested for economic analysts wishing to undertake evaluations alongside clinical trials.

Knowledge Representation Method of Product Principle Solution Based on Semantic Network Model

2010 ◽  
Vol 34-35 ◽  
pp. 1865-1869
Author(s):  
Xiao Ying Chen ◽  
Bin He
Keyword(s):  
Knowledge Representation ◽  
Network Model ◽  
Semantic Network ◽  
Design System ◽  
Product Knowledge ◽  
Knowledge Based ◽  
Principle Solution ◽  
Representation Method ◽  
Semantic Object ◽  
Knowledge Based Design

Product design is a problem-solving activity based on knowledge. This paper is devoted to presenting a systematic knowledge representation method of principle solution based on semantic network model. For the expression of product knowledge, the semantic object, constraints and their relationships among the expression of the semantic object network model are proposed step by step. Then the principle solution representation model based on semantic network model is put forwards. The knowledge representation of a car is given as an example, which demonstrates that this method is obviously helpful for knowledge-based design system and product innovation.

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