Development And Evaluation Of The Spleen And Stomach Disease PRO Scale-Gastroesphageal Disease Module(SSDPRO-GED)

BACKGROUND and OBJECTIVEThe Spleen and Stomach disease PRO scale(SSD-PRO) is a reliable and valid disease-specific instrument, which is used for measuring the medicine curative effect. Based on it, this study was going to develop the Gastroesphageal Disease (GED) Module in Spleen and Stomach disease PRO scale(SSDPRO-GED), and then evaluate it.METHODSAccording to the structured group methods of instrument development,the instrument with Chinese cultural background was developed, and evaluated by analyzing the data from 316 GED patients. By applying 5 kinds of nonparametric statistical methods, which include factor analysis, stepwise regression, discriminant analysis, ANOVA analysis, expert's judgment for the items weightiness and Crobach's a coefficient,54 items were kept to form a formal scale.RESULTSThe SSDPRO-GED scale include 4 domains with 8 facets in it. The correlation coefficient between the subtotal of odd and that of even item was 0.929; the correlation coefficients for each domain were 0.741,0.894,0.795 and 0.738. The Crobach's a of the whole scale was 0.948, when each domain were 0.942, 0.894,0.752,0.630. The result of Correlation analysis shows that, except the enviroment domain, each domain was correlated to the whole scale(r>0.6). And in physiology dimension, each item was correlated to it's own facet and it's own domain, in which,the correlation coefficients with their facets of the items of "pain in stomach and abdomen", "discomfort in stomach", "feel gloomy in stomach and abdomen" and "feel heavy in abdomen" are bigger than 0.7. Confirmatory factor analysis showed that the CFI of the scale was 0.94 and of 3 domains except independence domain were 1.00,0.91and 0.96 respectively.the results of IRT showed that all items didn't have uniform DIF and non-uniform DIF except item 14 in sex group and item 34, item35 in age group. The t-test showed that the SSDPRO-GED scale was able to reflect the difference between healthy people and patients (P<0.01)CONCLUSIONThe SSDPRO-GED subscale is a reliable and valid disease-specific instrument.