Wahlqvist, Peter; Guyatt, Gordon; Armstrong, David; … - In: PharmacoEconomics 25 (2007) 5, pp. 385-396
The English version of the WPAI-GERD showed good cross-sectional construct validity, and results indicated that the WPAI-GERD is responsive to change. Although the results also indicated that longitudinal construct validity may be poor, the overall findings suggest that further study of the...