Is adiposity an under-recognized risk factor for tendinopathy? A systematic review

Objective : Tendon injuries have been reported to occur more frequently in individuals with increased adiposity. Treatment also appears to have poorer outcomes among these individuals. Our objective was to examine the extent and consistency of associations between adiposity and tendinopathy.

Methods : A systematic review of observational studies was conducted. Eight electronic databases were searched (Allied and Complementary Medicine, Biological Abstracts, CINAHL, Current Contents, EMBase, Medline, SPORTDiscus, and Web of Science) and citation tracking was performed on included reports. Studies were included if they compared adiposity between subjects with and without tendon injury or examined adiposity as a predictor of conservative treatment success.

Results : Four longitudinal cohorts, 14 cross-sectional studies, 8 case-control studies, and 2 interventional studies (28 in total) met the inclusion criteria, providing a total of 19,949 individuals. Forty-two subpopulations were identified, 18 of which showed elevated adiposity to be associated with tendon injury (43%). Sensitivity analyses indicated a clustering of positive findings among studies that included clinical patients (81% positive) and among case-control studies (77% positive).

Conclusion : Elevated adiposity is frequently associated with tendon injury. Published reports suggest that elevated adiposity is a risk factor for tendon injury, although this association appears to vary depending on aspects of study design and measurement. Adiposity is of particular interest in tendon research because, unlike a number of other reported risk factors for tendon injury, it is somewhat preventable and modifiable. Further research is required to determine if reducing adiposity will reduce the risk of tendon injury or improve the results of treatment.

The inclusion of ‘then-test’ questions in post-test questionnaires alters post-test responses: a randomized study of bias in health program evaluation

Objectives Program evaluations are frequently based on ‘then-test’ data, i.e., pre-test collected in retrospect. While the application of the then-test has practical advantages, little is known about the validity of then-test data. Because of the collection of then-test in close proximity to post-test questions, this study was aimed at exploring whether the presence of then-test questions in post-test questionnaires influenced subjects’ responses to post-test.
Patients and methods To test the influence of then-test questions, we designed a randomized three-group study in the context of chronic disease self-management programs. Interventions had comparable goals and philosophies, and all 949 study participants filled out identical Health Education Impact Questionnaires (heiQ) at pre-test. At post-test, participants were then randomized to one of the following three groups: Group A responded to post-test questions only (n = 331); Group B filled out transition questions in addition to post-test (n = 304); and Group C filled out then-test questions in addition to post-test (n = 314).
Results Significant post-test differences were found in six of eight heiQ scales, with respondents who filled out then test questions reporting significantly higher post-test scores than respondents of the other groups.
Conclusions This study provides evidence that the inclusion of then-test questions alters post-test responses,
suggesting that change scores based on then-test data be interpreted with care.

Development of an inverse routine to predict residual stresses in the material based on a bending test

Bending and reverse bending are the dominant material deformations in roll forming, and hence property data derived from bend tests could be more relevant than tensile test data for numerical simulation of a roll forming process. Recent investigations have shown that residual stresses change the material behavior close to the yield in a bending test. So, residual stresses introduced during prior steel processing operations may affect the roll forming process, and therefore they need to be included in roll forming simulations to achieve improved model accuracy. Measuring the residual stress profile experimentally is time consuming and has limited accuracy while analytical models that are available require detailed information about the pre-processing conditions that is generally not available for roll forming materials. The main goal of this study is to develop an inverse routine that determines a residual stress profile through the material thickness based on experimental pure bend test data. A numerical model of the skin passing (temper rolling) process is performed to introduce a residual stress profile in DP780 steel sheet. The skin passed strips are used in a pure bending simulation to record moment-curvature data and this data is then applied in an inverse analysis to predict the residual stress profile in the material. Comparison of the residual stress profile predicted by the inverse routine with that calculated by finite element analysis (FEA) indicates an inverse approach combined with pure bend test may present an alternative to predict residual stresses in sheet metals.

Burden of epilepsy: a prevalence-based cost of illness study of direct, indirect and intangible costs for epilepsy

OBJECTIVES: We aimed to gauge the burden of epilepsy in China from a societal perspective by estimating the direct, indirect and intangible costs. METHODS: Patients with epilepsy and controls were enrolled from two tertiary hospitals in China. Patients were asked to complete a Cost-of-Illness (COI), Willingness-to-Pay (WTP) questionnaires, two utility elicitation instruments and Mini Mental State Examination (MMSE). Healthy controls only completed WTP questionnaire, and utility instruments. Univariate analyses were performed to investigate the differences in cost on the basis of different variables, while multivariate analysis was undertaken to explore the predictors of cost/cost component. RESULTS: In total, 141 epilepsy patients and 323 healthy controls were recruited. The median total cost, direct cost and indirect cost due to epilepsy were US$949.29, 501.34 and 276.72, respectively. Particularly, cost of anti-epileptic drugs (AEDs) (US$394.53) followed by cost of investigations (US$59.34), cost of inpatient and outpatient care (US$9.62) accounted for the majority of the direct medical costs. While patients' (US$103.77) and caregivers' productivity costs (US$103.77) constituted the major component of indirect cost. The intangible costs in terms of WTP value (US$266.07 vs. 88.22) and utility (EQ-5D, 0.828 vs. 0.923; QWB-SA, 0.657 vs. 0.802) were both substantially higher compared to the healthy subjects. CONCLUSIONS: Epilepsy is a cost intensive disease in China. According to the prognostic groups, drug-resistant epilepsy generated the highest total cost whereas patients in seizure remission had the lowest cost. AED is the most costly component of direct medical cost probably due to 83% of patients being treated by new generation of AEDs.