Fig. 2From: Validation of a derived version of the IPF-specific Saint George’s Respiratory QuestionnaireBland–Altman plot of the test–retest reliability of SGRQ-Ider in all stable patients. The solid line represents the mean difference and dashed lines represent 95% limits of agreement. SGRQ-Ider: IPF-specific version of the St. George’s Respiratory Questionnaire derived from results from the original St. George’s Respiratory QuestionnaireBack to article page