What does local tenderness say about the origin of pain? An investigation of cervical zygapophysial joint pain

BACKGROUND: Mechanical pain sensitivity is assessed in every patient with pain, either by palpation or by quantitative pressure algometry. Despite widespread use, no studies have formally addressed the usefulness of this practice for the identification of the source of pain. We tested the hypothesis that assessing mechanical pain sensitivity distinguishes damaged from healthy cervical zygapophysial (facet) joints. METHODS: Thirty-three patients with chronic unilateral neck pain were studied. Pressure pain thresholds (PPTs) were assessed bilaterally at all cervical zygapophysial joints. The diagnosis of zygapophysial joint pain was made by selective nerve blocks. Primary analysis was the comparison of the PPT between symptomatic and contralateral asymptomatic joints. The secondary end points were as follows: differences in PPT between affected and asymptomatic joints of the same side of patients with zygapophysial joint pain; differences in PPT at the painful side between patients with and without zygapophysial joint pain; and sensitivity and specificity of PPT for 2 different cutoffs (difference in PPT between affected and contralateral side by 1 and 30 kPa, meaning that the test was considered positive if the difference in PPT between painful and contralateral side was negative by at least 1 and 30 kPa, respectively). The PPT of patients was also compared with the PPT of 12 pain-free subjects. RESULTS: Zygapophysial joint pain was present in 14 patients. In these cases, the difference in mean PPT between affected and contralateral side (primary analysis) was −6.2 kPa (95% confidence interval: −19.5 to 7.2, P = 0.34). In addition, the secondary analyses yielded no statistically significant differences. For the cutoff of 1 kPa, sensitivity and specificity of PPT were 67% and 16%, respectively, resulting in a positive likelihood ratio of 0.79 and a diagnostic confidence of 38%. When the cutoff of 30 kPa was considered, the sensitivity decreased to only 13%, whereas the specificity increased to 95%, resulting in a positive likelihood ratio of 2.53 and a diagnostic confidence of 67%. The PPT was significantly lower in patients than in pain-free subjects (P < 0.001). CONCLUSIONS: Assessing mechanical pain sensitivity is not diagnostic for cervical zygapophysial joint pain. The finding should stimulate further research into a diagnostic tool that is widely used in the clinical examination of patients with pain.

Shareholder Value Maximization: What Managers Say and What They Do

This paper examines whether Swiss firms maximize shareholder value. To find out, we survey the goals of 313 listed and unlisted firms. We then examine whether managers’ decisions are consistent with their goals and analyze whether performance corresponds to intentions. Our results show that most managers pursue conflicting targets. Many also declare that they do not maximize shareholder value. And those who claim they do sometimes rely on investment criteria that are inconsistent with that target. Finally, we find that share-price performance is marginally better when managers claim to maximize shareholder value, particularly when stock prices have fallen.

Say on Pay: ein Überblick über Gestaltungsoptionen, ökonomische Konsequenzen und Erkenntnisse aus Empirie und Laborexperimenten

Unter dem Stichwort Say on Pay (SoP) haben in den letzen Jahren die meisten Länder der EU und die USA den Aktionären Abstimmungsrechte im Zusammenhang mit der Vergütung des Top-Managements eingeräumt. Zwischen den einzelnen Ländern bestehen jedoch erhebliche Unterschiede hinsichtlich der konkreten Ausgestaltung des SoP. Dieser Beitrag diskutiert die Wirkungen unterschiedlicher Gestaltungsoptionen des SoP auf die Anreizgestaltung und den Nutzen des Managements und der Aktionäre im Rahmen eines einfachen linearen Agency Modells. Dabei erweisen sich das vorvertragliche bindende SoP und das bedingt verpflichtende, nachvertragliche bindende SoP gegenüber den anderen untersuchten Varianten als überlegen. Während das konsultative SoP an seiner mangelnden Durchsetzbarkeit leidet, bietet das nachvertragliche bindende SoP Anreize für opportunistisches Verhalten auf Seiten der Aktionäre und führt deshalb zu Wohlfahrtsverlusten. In Ergänzung der Modellanalyse wird ein Überblick über die wichtigsten empirischen und experimentellen Studien zum Thema SoP gegeben und deren Inhalt im Lichte der Modellergebnisse diskutiert. Most countries of the European Union as well as the US recently introduced shareholder votes on the remuneration of executives, also referred to as “Say on Pay” (SoP). Interestingly, legislators in different jurisdictions opted for quite dissimilar voting right regimes. We provide an overview of the main regulatory approaches and discuss the potential impact of variations in SoP design on the structure of compensation contracts and the utility of shareholders and executives. We find that pre-contractual SoP and conditional post-contractual SoP with binding consequences are in the best interest of shareholders. By contrast, advisory SoP typically suffers from lacking enforceability. We also find that post-contractual SoP with binding consequences results in efficiency losses because it fuels moral hazard on the part of shareholders. We complement the theoretical analysis with a discussion of recent empirical and experimental studies on Say on Pay.

What does your neighbourhood say about you? A study of life expectancy in 1.3 million Swiss neighbourhoods

BACKGROUND Switzerland had the highest life expectancy at 82.8 years among the Organisation for Economic Co-operation and Development (OECD) countries in 2011. Geographical variation of life expectancy and its relation to the socioeconomic position of neighbourhoods are, however, not well understood. METHODS We analysed the Swiss National Cohort, which linked the 2000 census with mortality records 2000-2008 to estimate life expectancy across neighbourhoods. A neighbourhood index of socioeconomic position (SEP) based on the median rent, education and occupation of household heads and crowding was calculated for 1.3 million overlapping neighbourhoods of 50 households. We used skew-normal regression models, including the index and additionally marital status, education, nationality, religion and occupation to calculate crude and adjusted estimates of life expectancy at age 30 years. RESULTS Based on over 4.5 million individuals and over 400 000 deaths, estimates of life expectancy at age 30 in neighbourhoods ranged from 46.9 to 54.2 years in men and from 53.5 to 57.2 years in women. The correlation between life expectancy and neighbourhood SEP was strong (r=0.95 in men and r=0.94 women, both p values <0.0001). In a comparison of the lowest with the highest percentile of neighbourhood SEP, the crude difference in life expectancy from skew-normal regression was 4.5 years in men and 2.5 years in women. The corresponding adjusted differences were 2.8 and 1.9 years, respectively (all p values <0.0001). CONCLUSIONS Although life expectancy is high in Switzerland, there is substantial geographical variation and life expectancy is strongly associated with the social standing of neighbourhoods.