Background/Purpose:

Although
widely used in research studies, most of the radiographic scoring systems for
Rheumatoid Arthritis (RA) are not feasible in routine clinical practice as they
are time-intensive and require specialized expertise.  We have developed a
novel method [VARA (Veterans Affairs RA) scoring method] to evaluate for the
disease activity/damage in the RA hand joints.  Using the VARA registry, a
multi-center database of veterans with RA, our previous study found that VARA
scoring method correlated well with the widely accepted Modified Sharp/van der
Hejjde scoring method when assessed by a single experienced reader. In this
study we evaluated the inter-rater reliability of the VARA method using an experienced
reader and a pair of Rheumatology trainees.  

Methods:

The
VARA radiographic method involves assessment for the presence of erosions (E)
and joint space narrowing (JSN) in 3 joint regions of the hand and wrist,
metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints. The
presence of E or JSN each gives a score of 1 and absence gives a score of 0.
Hence, the maximum E or JSN score for each hand is 3 each with a minimum of 0. 
Total hand scores (E + JSN) for each hand could range from 0-6, for a total
score of 0-12 across both hands. The experienced reader (AE) used a
standardized 30-minute presentation to train the trainees (PV and AD) to assess
hand radiographs using the VARA method.

The
trainees and the experienced reader independently read the most recent
bilateral hand x-rays of 25 randomly selected patients using the VARA scoring method.
All readers were blinded to each other’s scoring results. Comparisons were made
using combined scores from both hands. Inter-rater reliability was assessed
several ways using a series of two-way, random, absolute agreement type
intraclass correlation coefficients with single measures [ICC2 (A,1)]. Measures
of E, JSN, and E + JSN were assessed using each pair of the three raters and
all three together.  Estimates were made of the time needed for each rater to
complete the scoring of a set of radiographs.

Results:

Inter-rater
reliability measures, which are estimates of the proportion of variability in
scores accounted for by differences in true scores, were fairly high with E +
JSN scores for any pair of raters producing an ICC in the range of 0.680-0.807
and all three raters combined yielding an ICC of 0.765 (Table ). The time
needed for VARA scores by the expert was estimated to be 3.3 minutes and the
time needed for the trainees was 3.5 minutes.

Conclusion:

The
VARA method is a very practical method of radiographic scoring and may be
particularly useful for observational studies and in clinical practice where
quantitative assessments of joint damage at a single time point by a single
rater are needed.  It is easy to learn and practical to perform in regular
clinical practice and the reliability of this measure is quite good.