Rheumatoid Arthritis: Kostense P

Bruynesteyn K, Boers M, Kostense P, van der Linden S, van der Heijde D. · Department of Internal Medicine, Division of Rheumatology, University Hospital Maastricht, PO Box 5800, 6202 AZ Maastricht, The Netherlands. · Ann Rheum Dis. · Pubmed #15286006 links to  free full text

Abstract: Progression of radiological joint damage is usually based on the simultaneous assessment of a series of films from an individual patient ("paired", with or without known sequence). In this setting the degree of progression that can be reliably detected above the measurement error is best determined by the smallest detectable change, and overestimated by the traditionally calculated smallest detectable difference. This knowledge is important for calculation of the proportion of patients showing radiographic progression in clinical trials.

van Der Heijde D, Boonen A, Boers M, Kostense P, van Der Linden S. · Department of Internal Medicine, Division of Rheumatology, University Hospital Maastricht, Maastricht, The Netherlands. · Rheumatology (Oxford). · Pubmed #10587548 links to  free full text

Abstract: OBJECTIVE: To determine the influence of reading series of films in chronological order, in pairs with unknown time sequence, or as single films, on precision and sensitivity to change. METHODS: Two studies were performed with 10 and 12 patients fulfilling the American College of Rheumatology criteria. In Study 1, two sets of films with a 1 yr interval were scored in chronological order, in pairs, and as single films. In Study 2, four sets of films, with a 1 yr interval each, were scored in chronological order, as single films and as single-pair (right and left together). All films were scored with the Sharp/van der Heijde method by two independent observers. Data were analysed with a repeated measures ANOVA using a full mixed effects model. Two generalizability (G) coefficients were constructed for reliability and for change. RESULTS: Study 1: the interobserver reliability was similar for the three methods (G(reliability) chronological 0.94, paired 0.88, single 0.93); progression was a mean increase (averaged over patients, observers and methods) from 26 to 37 (P=0.046). The sensitivity for change was greater for the chronological than for the paired and single scoring (G(change) 0.39, 0.22 and 0.24, respectively). Study 2: the interobserver reliability was 0.86 for chronological, 0.76 for single-pair and 0.91 for single readings. Significantly more progression was measured with the chronological compared with the single-paired and single methods (15.9 vs 8.5 and 8.3; P=0.0001). A constant progression was suggested by chronological reading, in contrast to a stabilization in the other two methods after 1 yr. CONCLUSION: Reading films in chronological order is most sensitive to change in a time period up to 3 yr follow-up; this was already present after 1 yr, but even more pronounced with longer follow-up.