The effects of a lutein-based supplement on objective and subjective measures of retinal and visual function in eyes with age-related maculopathy - a randomised controlled trial

Lutein and zeaxanthin are lipid-soluble antioxidants found within the macula region of the retina. Links have been suggested between increased levels of these carotenoids and reduced risk for age-related macular disease (ARMD). Therefore, the effect of lutein-based supplementation on retinal and visual function in people with early stages of ARMD (age-related maculopathy, ARM) was assessed using multi-focal electroretinography (mfERG), contrast sensitivity and distance visual acuity. A total of fourteen participants were randomly allocated to either receive a lutein-based oral supplement (treated group) or no supplement (non-treated group). There were eight participants aged between 56 and 81 years (65·50 (sd 9·27) years) in the treated group and six participants aged between 61 and 83 years (69·67 (sd 7·52) years) in the non-treated group. Sample sizes provided 80 % power at the 5 % significance level. Participants attended for three visits (0, 20 and 40 weeks). At 60 weeks, the treated group attended a fourth visit following 20 weeks of supplement withdrawal. No changes were seen between the treated and non-treated groups during supplementation. Although not clinically significant, mfERG ring 3 N2 latency (P= 0·041) and ring 4 P1 latency (P= 0·016) increased, and a trend for reduction of mfERG amplitudes was observed in rings 1, 3 and 4 on supplement withdrawal. The statistically significant increase in mfERG latencies and the trend for reduced mfERG amplitudes on withdrawal are encouraging and may suggest a potentially beneficial effect of lutein-based supplementation in ARM-affected eyes. Copyright © 2012 The Authors.

Cutting the Gordian knot [?]:a response to Lukka and Vinnari (2014)

Purpose – The purpose of this paper is to constructively discuss the meaning and nature of (theoretical) contribution in accounting research, as represented by Lukka and Vinnari (2014) (hereafter referred to as LV). The authors aim is to further encourage debate on what constitutes management accounting theory (or theories) and how to modestly clarify contributions to the extant literature. Design/methodology/approach – The approach the authors take can be seen as (a)n interdisciplinary literature sourced analysis and critique of the movement’s positioning and trajectory” (Parker and Guthrie, 2014, p. 1218). The paper also draws upon and synthesizes the present authors and other’s contributions to accounting research using actor network theory. Findings – While a distinction between domain and methods theories … may appear analytically viable, it may be virtually impossible to separate them in practice. In line with Armstrong (2008), the authors cast a measure of doubt on the quest to significantly extend theoretical contributions from accounting research. Research limitations/implications – Rather than making (apparently) grandiose claims about (theoretical) contributions from individual studies, the authors suggest making more modest claims from the research. The authors try to provide a more appropriate and realistic approach to the appreciation of research contributions. Originality/value – The authors contribute to the debate on how theoretical contributions can be made in the accounting literature by constructively debating some views that have recently been outlined by LV. The aim is to provide some perspective on the usefulness of the criteria suggested by these authors. The authors also suggest and highlight (alternative) ways in which contributions might be discerned and clarified.