Background Patient's global assessment (PtGA) is one of the most widely used patient reported outcomes in rheumatoid arthritis (RA) that reflects both disease activity and other factors. PtGA is onymous and obtained at hospital, which may cause a conscious or unconscious bias, whereas PtGA obtained anonymously may be free from any bias. The credibility of PtGA to report RA patient outcomes has been usually investigated by assessing test-retest reliability. There has been no study comparing routine PtGA and PtGA where patients answered anonymously.
Objectives The aim of this study was to compare routinely obtained in-hospital PtGA before clinical examination with those answered anonymously at home. Additionally, physician's global assessment (PhyGA) was compared with routine PtGA and anonymized PtGA
Methods We asked RA patients (n=389) to answer and mail the PtGA test anonymously, Clinical data regarding disease duration, stage, class, swollen joint counts, tender joint counts, pain visual analog scale (VAS), PhyGA, Health Assessment Questionnaire (HAQ), EuroQOL five dimensions questionnaire (EQ5D), Kessler 6 scale (anxiety/ depression), treatment data, laboratory data, and socioeconomic factors were collected simultaneously. We compared the PtGA that is routinely surveyed at hospital before clinical examination with those surveyed anonymously at home. We calculated a discrepancy score by subtracting anonymized PtGA from routine in-hospital PtGA. We defined (1) positive discrepancy when routine PtGA was over-rated relative to the anonymized PtGA; (2) negative discrepancy when routine in-hospital PtGA was under-rated relative to the anonymized PtGA.
Results The anonymized PtGA score was higher than routinely evaluated in-hospital PtGA (p<0.0001). The anonymized PtGA poorly correlated with routine in-hospital PtGA (r=0.426, p<0.0001). We compared patients who had discordance between in-hospital PtGA and anonymized PtGA. We used 3 models in which the discordance between both PtGAs was set at 10 mm, 20 mm, or 30 mm. If we adopted 30 mm as discordance, the pain scale remained to be a risk factor of positive discrepancy (higher in-hospital PtGA than anonymized PtGA). If we adopted 20 mm or 10 mm as discordance, the pain scale remained to be a risk factor of positive discrepancy and remaining low quality of life (QOL) negative discrepancy (lower in-hospital PtGA than anonymized PtGA) after multivariate analysis. The discordance between PhyGA and routine PtGA are associated with high pain VAS. The discordance between PhyGA and anonymized PtGA is associated with tender joint counts, swollen joint counts, and low QOL.
Conclusions Discrepancy exists between routine in-hospital PtGA and anonymized PtGA.
The high pain VAS scale and low QOL are risk factors that could make the difference between routine PtGA from anonymized PtGA. There is a possibility that high pain VAS score and low QOL influence the reliability of PtGA.
Disclosure of Interest None declared