Using Smalltalk as a Reflective Executable Meta-Language

Object-oriented meta-languages such as MOF or EMOF are often used to specify domain specific languages. However, these meta-languages lack the ability to describe behavior or operational semantics. Several approaches used a subset of Java mixed with OCL as executable meta-languages. In this paper, we report our experience of using Smalltalk as an executable and integrated meta-language. We validated this approach in incrementally building over the last decade, Moose, a meta-described reengineering environment. The reflective capabilities of Smalltalk support a uniform way of letting the base developer focus on his tasks while at the same time allowing him to meta-describe his domain model. The advantage of our this approach is that the developer uses the same tools and environment

Back related outcome assessment instruments

A literature review of the most widely used condition specific, self administered assessment questionnaires for low back pain had been undertaken. General and historic aspects, reliability, responsiveness and minimum clinically important difference, external validity, floor and ceiling effects, and available languages were analysed. These criteria, however, are only part of the consideration. Of similar importance are the content, wording of questions and answers in each of the six questionnaires and an analysis of the different score results. The issue of score bias is discussed and suggestions are given in order to increase the construct validity in the practical use of the individual questionnaires.

Content comparison of health-related quality of life instruments for COPD

BACKGROUND: Due to the increasing importance of quality of life assessments in chronic obstructive pulmonary disease (COPD) patients, and the increased use of the International Classification of Functioning, Disability and Health (ICF) for comparative purposes it is essential to understand the relationship between health-related quality of life (HRQL) instruments and the ICF. OBJECTIVE: The objective of this study was to compare the content of recommended COPD-specific HRQL instruments using the ICF as reference. COPD-specific instruments mentioned in widely accepted guidelines were linked to the ICF using standardized linking rules. The degree of agreement between various health professionals was assessed by calculating the kappa statistic. RESULTS: Eleven instruments were included. They varied strongly in the number of concepts contained and the number of ICF categories used to map these concepts. A total of 548 concepts were identified and linked to 60 different ICF categories. Only the single category 'dyspnea' was covered by all instruments, whilst 21 categories were unique to specific instruments. The relationships of the measures with the ICF were identified. CONCLUSIONS: This study may aid researchers and clinicians to choose the most appropriate instrument for a specific purpose as well as help compare studies that have used different instruments for HRQL assessment.

Macular thickness measurements in healthy eyes using six different optical coherence tomography instruments

To compare central retinal thickness (CRT) measurements in healthy eyes by different commercially available OCT instruments and to compare the intersession reproducibility of such measurements.

Content comparison of health-related quality of life instruments for obstructive sleep apnea

BACKGROUND AND PURPOSE: Due to the increasing importance of quality of life assessments in obstructive sleep apnea (OSA) patients and due to an increased use of the International Classification of Functioning, Disability and Health (ICF), for comparative purposes it is essential to understand the relationship between health-related quality of life (HRQOL) instruments and the ICF. The purpose of this study was to compare the content covered by OSA-specific instruments using the ICF. PATIENTS AND METHODS: OSA-specific instruments were identified, including the Calgary Sleep Apnea Quality of Life Index, the Functional Outcomes of Sleep Questionnaire, the Obstructive Sleep Apnea Patient-Oriented Severity Index, and the Quebec Sleep Questionnaire, and linked to the ICF by six health professionals according to standardized guidelines. The degree of agreement between health professionals was calculated by means of the kappa statistic. RESULTS: A total of 308 concepts were identified and linked to 78 different ICF categories; 35 categories of the component body function, one category of the component body structure, 38 categories of the component activities and participation, and four categories of the component environmental factors. Only contents within the chapters mental functions, mobility and social life were addressed by all instruments. Forty-seven categories were covered by only one instrument. CONCLUSION: The ICF proved highly useful for the comparison of HRQOL instruments. This analysis may help researchers and clinicians to choose the most appropriate HRQOL instrument for a specific purpose as well as help to compare study outcomes of studies using different instruments for HRQOL assessment.

Identification of prognostic factors for chronicity in patients with low back pain: a review of screening instruments

Low back pain (LBP) is currently the most prevalent and costly musculoskeletal problem in modern societies. Screening instruments for the identification of prognostic factors in LBP may help to identify patients with an unfavourable outcome. In this systematic review screening instruments published between 1970 and 2007 were identified by a literature search. Nine different instruments were analysed and their different items grouped into ten structures. Finally, the predictive effectiveness of these structures was examined for the dependent variables including "work status", "functional limitation", and "pain". The strongest predictors for "work status" were psychosocial and occupational structures, whereas for "functional limitation" and "pain" psychological structures were dominating. Psychological and occupational factors show a high reliability for the prognosis of patients with LBP. Screening instruments for the identification of prognostic factors in patients with LBP should include these factors as a minimum core set.

Meta-Environment and Executable Meta-Language using Smalltalk: an Experience Report

Object-oriented modelling languages such as EMOF are often used to specify domain specific meta-models. However, these modelling languages lack the ability to describe behavior or operational semantics. Several approaches have used a subset of Java mixed with OCL as executable meta-languages. In this experience report we show how we use Smalltalk as an executable meta-language in the context of the Moose reengineering environment. We present how we implemented EMOF and its behavioral aspects. Over the last decade we validated this approach through incrementally building a meta-described reengineering environment. Such an approach bridges the gap between a code-oriented view and a meta-model driven one. It avoids the creation of yet another language and reuses the infrastructure and run-time of the underlying implementation language. It offers an uniform way of letting developers focus on their tasks while at the same time allowing them to meta-describe their domain model. The advantage of our approach is that developers use the same tools and environment they use for their regular tasks. Still the approach is not Smalltalk specific but can be applied to language offering an introspective API such as Ruby, Python, CLOS, Java and C#.

Addressing micropollution by linking problem characteristics to policy instruments

What characterizes micropollution as a policy problem and which policy instruments are adequate to regulate micropollution, given the specific problem features? In this article, problem characteristics of micropollution are systematically analyzed and linked to potential policy solutions.