Macular thickness measurements in healthy Norwegian volunteers: an optical coherence tomography study

<p>Abstract</p> <p>Background</p> <p>Ethnic, intersubject, interoperator and intermachine differences in measured macular thickness seem to exist. Our purpose was to collect normative macular thickness data in Norwegians and to evaluate the association between macular thickness and age, gender, parity, and contraception status.</p> <p>Methods</p> <p>Retinal thickness was measured by Stratus Optical Coherence Tomography in healthy subjects. Mean macular thickness (MMT) was analyzed by repeated measures ANOVA with three dependent regional MMT-variables for interaction with age, gender, parity and oral contraception use. Exploratory correlation with age by the Pearson correlation test, both before and after stratification by gender was performed. Differences in MMT between older and younger subjects, between oral contraception users and non-users, as well as parous and nulliparous women were studied by post-hoc Student's t-tests.</p> <p>Results</p> <p>Central MMT in Norwegians was similar to values earlier reported in whites. MMT in central areas of 1 and 2.25 mm in diameter were higher in males than in females. In younger subjects (≤43 years) differences in MMT between genders were larger than in the mixed age group, whereas in older subjects (>43 years) the small differences did not reach the set significance level. No differences were found in minimal foveolar thickness (MMFT) between the genders in any age group.</p> <p>Mean foveal thickness (1 mm in diameter) was positively associated with age in females (r = 0.28, p = 0.03). MMFT was positively associated with age in all groups and reached significance both in females and in mixed gender group (r = 0.20, p = 0.041 and r = 0.26, p = 0.044 respectively).</p> <p>Mean foveal thickness and MMFT were significantly higher in parous than in nulliparous women, and age-adjusted ANOVA for MMFT revealed a borderline effect of parity.</p> <p>Conclusions</p> <p>Age and gender should be taken into consideration when establishing normal ranges for MMT in younger subjects. The gender difference in retinal thickness in young, but not older adults suggests a gonadal hormonal influence. The possible association between parity and retinal structure and its clinical relevance, should be studied further.</p

Justifying Competition Law in the Face of Consumers\u27 Bounded Reality

Series: Economic Analysis of Law in European Legal Scholarship, vol. 7 The central economic justification for competition law is that the protection of competition promotes welfare. In particular, perfect competition among firms catering to consumer demand for goods and services maximizes social welfare by generating both allocative and productive efficiencies. This standard account rests inter alia, however, on the assumption that consumer demand reveals rational consumer beliefs and preferences. Hence, an otherwise competitive market that caters to “erroneous” demand based on consumers’ mistaken beliefs or constructed, ad-hoc preferences will fail to maximize efficiency and welfare. Yet, empirical behavioural findings show that boundedly rational consumers exhibit mistaken beliefs and constructed preferences regarding some of the products and services they demand in the market. These behavioural findings, therefore, challenge the conventional economic justification for the important role served by competition law and its institutions as the means for protecting competition in the market. After explaining the challenges that the behavioural evidence poses for the standard economic account, this chapter outlines two key elements of the behavioural economic case that suggest competition law still has an important role to play in advancing efficiency and welfare even after the bounded rationality of consumers is accounted for, albeit perhaps a more modest role than competition law discourse usually ascribes to it

Two Contexts for Economics in Competition Law - Justifying Competition Law in the Face of Consumers' Bounded Rationality - Deterrence Effects and Competitive Effects

Competition law accommodates two different contexts within which economics may be applied, each defined by a distinct type of cause-effect relationships. First, there are effects of competition law on business conduct (deterrence effects), embodying the fact that businesses take into account legal sanctions when planning their actions. The field studying these effects is Economic Analysis of Law. Second, there are effects of business conduct on competition (competitive effects), which occur through the influence of businesses with market power on behaviour of their customers, suppliers and competitors. This influence falls within the ambit of Industrial Organization. Awareness of the distinction makes it possible to appreciate certain aspects of the application of economics to competition law issues. For instance, within the discourse on this application, the context of competitive effects receives significantly more attention than the context of deterrence effects. Also the often voiced observation that economics and competition law are closely related regards predominantly the former context