Evaluation of status and quality of life in patients with ankylosing spondylitis– validation of Czech versions of Bath questionnaires – BAS-G, BADAI and BASFI

Overview

The questionnaires evaluating functional status, disease activity and global status of patients withankylosing spondylitis were translated into Czech language. These included Bath AnkylosingSpondylitis Disease Activity Index (BASDAI), Bath Ankylosing Functional Index (BASFI) and BathAnkylosing Spondylitis Disease – Global Score (BAS-G). The translation of each questionnaire wasdiscussed, adapted to local conditions, then retranslated and compared with original version. Thefinal Czech versions have been tested for their reliability and validity in a group of patients withAS who were indicated to balneotherapy in Jáchymov spa. The evaluation of questionnaires BAS-G,BASDAI and BASFI demonstrated high and sufficient value of reliability and validity for the totalscore as well as for its particularcomponents.Highcongruence in serialandquantitative correlationof both outcomes was demonstrated by reciprocal correlation analysis. Global assessment accordingto BAS-G score significantly correlated with the subjective status of patients and is fully in harmonywith the general intent of the scale. Moreover, BASDAI significantly negatively correlated withThomayer’s and fleche distances. BASFI score is an index mostly related to the objective status ofAS, significantly correlates with all the distances and can be also used for all stages of the disease.Internal integrity of the Czech versions of questionnaires assessed by Cronbach coefficient alphais 0.914 for BASDAI score and 0.929 for BASFI score. These values are very satisfactory and showhigh internal integrity of questionnaires. When balneotherapy has finished, the improvement in theassessment of questionnaires was demonstrated and relative improvement, near 25%, was expressedalso in patients with stages II–III. In conclusion, Czech version of questionnaires BASDAI, BASFIand BAS-G for ankylosing spondylitis showed sufficient reliability and validity.

Key words:
ankylosing spondylitis, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI),Bath Ankylosing Functional Index (BASFI), Bath Ankylosing Spondylitis – Global Score (BAS-G)