Citation:Su Y, Willis G, Salomon JA. Improving Vignette Descriptions and Question Formats to Measure Distance Vision: Evidence from Cognitive Interviews among Students in China. Field MethodsField Methods. 2017 :1525822X16680810.Download CitationBibTex Tagged XML Download su_et_al_field_methods_2017.pdf165 KB Last updated on 03/21/2017