Adult Strabismus (AS 20) AS-20 Questionnaire - a quality of life questionnaire for adult strabismus. AS-20 Questionnaire (English) AS-20 Questionnaire (Spanish SAS1 version) - for use in SAS1 protocol Only AS-20 Questionnaire (Spanish - Combined Latin American/European version). From translation, back-translation, and testing to confirm content. Specific questions regarding the Spanish version can be directed to David Leske at leske.david@mayo.edu AS-20 Questionnaire (Dutch version). From translation, back-translation, and testing to confirm content. Specific questions regarding the Dutch version can be directed to Hinke-Marijke Jellema at h.m.jellema@amsterdamumc.nl AS-20 Rasch Lookup Table