Details

Autor(en) / Beteiligte

• Wu, YingXing, MD
• Takkenberg, Johanna J.M., MD, PhD
• Grunkemeier, Gary L., PhD

Titel

Measuring Follow-Up Completeness

Ist Teil von

• The Annals of thoracic surgery, 2008-04, Vol.85 (4), p.1155-1157

Ort / Verlag

New York, NY: Elsevier Inc

Erscheinungsjahr

2008

Quelle

MEDLINE

Beschreibungen/Notizen

• Completeness of follow-up is often used as a measure of the quality of follow-up, but the method used to compute it is often not declared. An ideal measure should be based on follow-up years instead of patients. Clark, Altman, and De Stavola proposed such a measure, called “C”, which is the percentage of the maximum possible follow-up years, as of a given date, that has actually been accounted for or observed. However, such a measure will underestimate the true completeness, because the denominator (maximum possible follow-up years) does not account for unobserved patient deaths occurring before that date, and therefore, it is realistically unachievable. We propose a modification, C*, of Clark’s C, which accounts for the effect of unobserved patient deaths in attenuating the maximum potential follow-up, and thus gives a higher percentage for achieved follow-up completeness. We validated this theoretical improvement by comparing the values of C and C* computed for our long-term coronary artery bypass graft patients to the true completeness, which was obtained by using the National Death Index to complete our missing follow-up data. Using Clark’s C, the follow-up completeness was 80.4% and using our C* it is 84.5%, whereas the true follow-up completeness based on National Death Index information was 85.0%.