Feldtkeller Ernst, Erlendsson Jon
Ankylosing Spondylitis International Federation, Michaeliburgstr. 15, 81671 Munich, Germany.
Rheumatol Int. 2008 May;28(7):693-6. doi: 10.1007/s00296-007-0499-y. Epub 2007 Dec 12.
Two definitions of the "disease duration" of ankylosing spondylitis (AS) have been used in the literature: (1) duration since first symptoms connected with AS and (2) duration since diagnosis of AS. To investigate how useful these definitions are for research, we reinvestigated the data of four surveys completed by patients with AS in the years since 1996. We found that the majority of the patients remembered the age at first symptoms with an accuracy of <or=1 year, and that the difference between both definitions (the delay in diagnosis) was between 9.8 and 10.4 years on average, with extreme values of more than 30 years being not very seldom. Because the error made using the duration since diagnosis as "disease duration" is much larger than the inaccuracy taken into account using the duration since first symptoms, only the duration since first symptoms connected with AS should be used as definition for the term "disease duration" of AS.
文献中使用了两种强直性脊柱炎（AS）“病程”的定义：（1）自首次出现与AS相关症状起的时长，以及（2）自AS诊断起的时长。为研究这些定义对研究的有用程度，我们重新分析了自1996年以来AS患者完成的四项调查数据。我们发现，大多数患者能准确记起首次出现症状时的年龄，误差≤1岁，并且两种定义之间的差异（诊断延迟）平均在9.8至10.4年之间，超过30年的极端值并不少见。由于将自诊断起的时长用作“病程”所产生的误差远大于使用自首次出现症状起的时长所考虑到的不准确性，因此仅应将自首次出现与AS相关症状起的时长用作AS“病程”这一术语的定义。
