"the validity of the pisa study has increasingly been called into question" in German The validity of the PISA study has increasingly been called into question. An der Aussagekraft der PISA-Studie werden zunehmend Zweifel laut. Detailed translations for "the validity of the pisa study has increasingly been called into question" The validity of the PISA study has increasingly been called into question. The validity of the PISA study has increasingly been called into question. An der Aussagekraft der PISA-Studie werden zunehmend Zweifel laut.