To analyze visual analog scales (VAS) for pain and patient global estimate on a Multidimensional Health Assessment Questionnaire (MDHAQ) in formats other than a traditional 10 cm horizontal line, designed to facilitate scoring on MDHAQ in usual clinical care.
The MDHAQ with VAS for pain and global estimate was completed by each patient at each visit. VAS formats other than a traditional (unnumbered) 10 cm horizontal line based on 21 circles at 0.5 intervals were analyzed. Formats included unnumbered, symbol at the 11th circle, numbers and/or squares (instead of circles) at selected intermittent scores, and numbers at each circle. Analyses were performed to study the time to score MDHAQ with different VAS formats, possible "clustering" of responses in any format, particularly with intermittent numbers and/or symbols, and test-retest reliability of various formats.
The median time to score MDHAQ with a 10 cm line VAS was 15.6 seconds, compared to 7.4 seconds for the 21 numbered circle VAS. No other format was scored in fewer seconds. Clustering was seen for scores of VAS formats with intermittent numbers or symbols, which rendered them unsuitable for use. No clustering was seen for the 21 numbered circle VAS format, for which test-retest agreement was significant, and similar to the 10 cm line VAS format.
A 21 numbered circle VAS may be a desirable alternative to a 10 cm horizontal line, yielding similar results and requiring less than half the time to score.