1.Impact of Rating Scale Categories on Reliability and Fit Statistics of the Malay Spiritual Well-Being Scale using Rasch Analysis
Aqil Mohammad Daher ; Syed Hassan Ahmad ; Than Winn ; Mohd Ikhsan Selamat
Malaysian Journal of Medical Sciences 2015;22(3):48-55
Background: Few studies have employed the item response theory in examining reliability. We conducted this study to examine the effect of Rating Scale Categories (RSCs) on the reliability and fit statistics of the Malay Spiritual Well-Being Scale, employing the Rasch model.
Methods: The Malay Spiritual Well-Being Scale (SWBS) with the original six; three and four newly structured RSCs was distributed randomly among three different samples of 50 participants each.
Results: The mean age of respondents in the three samples ranged between 36 and 39 years old. The majority was female in all samples, and Islam was the most prevalent religion among the respondents. The predominating race was Malay, followed by Chinese and Indian. The original six RSCs indicated better targeting of 0.99 and smallest model error of 0.24. The Infit Mnsq (mean square) and Zstd (Z standard) of the six RSCs were “1.1”and “-0.1”respectively. The six RSCs achieved the highest person and item reliabilities of 0.86 and 0.85 respectively. These reliabilities yielded the highest person (2.46) and item (2.38) separation indices compared to other the RSCs.
Conclusion: The person and item reliability and, to a lesser extent, the fit statistics, were better with the six RSCs compared to the four and three RSCs.
2.Chemical composition and antioxidant activity of a Lebanese plant Euphorbia macroclada schyzoceras
Hussein FARHAN ; Hassan RAMMAL ; Akram HIJAZI ; Ahmad DAHER ; Mohamad REDA ; Hussein ANNAN ; Ali CHOKR ; Ali BASSAL ; Bassam BADRAN
Asian Pacific Journal of Tropical Biomedicine 2013;(7):542-548
Objective:To determine the chemical composition, total phenolic and total flavonoid contents of the crude extracts from leaves and stems of a Lebanese plant Euphorbia macroclada schyzoceras (E. macroclada), and to evaluate their antioxidant potential using DPPH, H2O2, and chelating of ferrous ions tests. Methods:Quantification of the total phenolic and total flavonoid contents of the crude extracts from leaves and stems and the antioxidant activities were evaluated using spectrophotometric analyses. The chemical composition has been estimated using different techniques such as IR, LC/MS and NMR. Results:Ethanolic extract from leaves of E. macroclada was better than aqueous extract and showed higher content in total phenolic and total flavonoid than found in the stems. On the other hand, using DPPH and H2O2 tests, this extract from leaves showed higher antioxidant capacity than aqueous extract. However, using the chelating of ferrous ions test, the antioxidant activity of the aqueous extract of both stems and leaves was stronger than that of ethanolic once. The chemical composition of the whole plant showed the presence of some aromatic compounds and fatty acids. Conclusions:Both ethanolic and water extracts from both parts of this plant are effective and have good antioxidant power. So, this plant can be used in the prevention of a number of diseases related to oxidative stress.