R.E. Lee

Successive comparisons between ordered treatments

Abstract A method is proposed for one- and two-sided comparison of means of adjacent ordered treatments with the one-way layout or randomized complete block model while maintaining a designated overall Type I error rate. For the case of equal sample sizes and r ⩽ 6 treatments, tables of exact critical values are presented and the improvement over existing conservative methods is investigated. Approximate techniques are proposed for r ⩾ 7.

Differences in antioxidant levels of fresh, frozen and freeze-dried strawberries and strawberry jam

Abstract The present study was conducted to determine differences in antioxidant levels of fresh, frozen, and freeze-dried strawberries, and strawberry jam. Hydrophilic antioxidant activity (HAA) and lipophilic antioxidant activity (LAA) were measured using the ABTS/H2O2/HRP decoloration method. HAA and LAA were then summed to calculate the total antioxidant activity (TAA). Mean differences in HAA and LAA were analyzed using one-way analysis of variance and Dunnetts T3 pairwise comparisons. The mean TAA for freeze-dried strawberries based on an ‘as consumed’ weight (95% confidence interval [CI]: 29.58, 30.58) was significantly higher than for fresh (95% CI: 3.18, 3.66), frozen (95% CI: 2.58, 2.79), and jam (95% CI: 1.10, 1.22). The mean TAA based on dry weight for fresh strawberries (95% CI: 40.48, 46.67) was significantly higher than for freeze-dried (95% CI: 29.58, 30.58), frozen (95% CI: 24.62, 26.59), and jam (95% CI: 1.48, 1.64). Results agree with previous studies reporting that strawberries are a valuable source of antioxidants for consumers.

Cooking does not decrease hydrophilic antioxidant capacity of wild blueberries

The present study examined the effects of domestic cooking methods on the hydrophilic antioxidant activity (HAA) of wild blueberries. Baked, microwaved, simmered, and pan-fried frozen wild blueberries, and a thawed uncooked control, were analyzed for HAA using an ABTS/H2O2/HRP decoloration method. All cooking treatments were derived from recipes using wild blueberries, and were performed in triplicate. A randomized block design was used to determine whether there were statistical differences in antioxidant content after cooking and between each of the trials. There were no statistically significant decreases after cooking the thawed berries. On both a fresh weight and a dry weight basis, pan-fried blueberries had significantly higher HAA than baked, simmered, and control blueberries (P<0.05). Antioxidants in wild blueberries appear to be heat stable since cooked berries retained significant HAA. Cooked wild blueberries can be recommended as a good source of dietary antioxidants.

Link between diet and cardiovascular disease in Latin America and the Caribbean using geographic information systems

OBJECTIVE To determine the visual, spatial, and/or statistical relationships between food availability/dietary patterns and cardiovascular disease (CVD) in Latin America and the Caribbean (LAC). METHODS CVD mortality rates and diet information (the number of kilocalories and amount of alcohol, fats, fish, fruits, meats, sugars, and vegetables available per person daily) were obtained from internationally available databases. The analyses included 32 LAC countries with sufficient data (15 of 47 had been excluded for incomplete data). Pearsons correlations (r) were used to determine relationships between diet and CVD mortality, and multiple linear regression analysis was conducted to identify predictors of mortality. ArcGIS version 9.2 (Environmental Systems Research Institute, Inc., Redlands, California, United States) was used to construct maps to explore visual relationships between CVD and diet. RESULTS No relationships were found between CVD and alcohol, fruit, meat, sugar, or vegetable intake. Statistically significant, positive correlations were found between oil-crops (r = 0.680, P = 0.000) and fish and seafood (r = 0.411, P = 0.019) and CVD mortality. Regression analysis revealed that high kilocalorie availability was a predictor of low CVD mortality (P = 0.020). High oil-crop availability was a predictor of high CVD mortality (P = 0.000). Maps constructed show visual relationships between availability of fish and seafood, kilocalories, and oil-crops, and CVD mortality. CONCLUSIONS Fish and seafood, kilocalorie, and oil-crop availability appear to be related to CVD mortality, but further investigation is needed. Associations between diet and CVD mortality create the opportunity to target specific countries for nutrition education and CVD prevention programs.

Distribution-free multiple comparisons between successive treatments

Distribution-free methods are proposed for one- and two-sided comparison of adjacent pairs of r≧3 ordered treatments in the one-way layout. A table of exact probability points isgiven for use with Mann Whitney statistics in the equal sample size case for one-sided inference with r = 3 or 4 and for two-sided inference with r = 3. Approximations are investigated for use with larger r. Asymptotic probability points are found for use with all Chernoff-Savage statistics. Asymptotically optimal designs for these methods use approximately equal numbers of observations for even r and approximately ((r+l)/(r-1))1/2 times as many observations from each even numbered treatment as from each odd numbered treatment when r is odd. The asymptotic relative efficiency oftwo proceduresis identical to that of their two-sample counterparts