Table 2.

Negative binomial regression results to identify predictors of the physician (MD) and patient (Pt) global assessments of disease severity in the Canadian data. This table contains the estimated OR with 95% CI for the 6 different models. Values in bold type indicate CI that do not overlap with 0. Note that creatinine was transformed by taking the square root in order to improve model assumptions and decrease the influence of outlying points. Results are given as square root of creatinine. The coefficient < 1 for fatigue reflects the fact that for the measurement of fatigue, lower scores represent worse fatigue.

All CovariatesClinical Covariates OnlyPatient Reported Covariates Only
MD AssessmentPt AssessmentMD AssessmentPt AssessmentMD AssessmentPt Assessment
Age1.000 (0.997, 1.006)1.006 (0.997, 1.004)1.004 (0.992, 1.009)0.999 (0.994, 1.004)1.000 (0.995, 1.004)1.000 (0.996, 1.003)
Female1.027 (0.893, 1.184)1.042 (0.931, 1.168)0.974 (0.838, 1.134)0.964 (0.822, 1.130)0.903 (0.777, 1.051)0.996 (0.893, 1.112)
White0.962 (0.849, 1.092)1.046 (0.947, 1.158)0.971 (0.851, 1.109)1.017 (0.887, 1.165)0.995 (0.866, 1.145)1.061 (0.961, 1.175)
Disease duration0.993 (0.987, 0.999)0.997 (0.992, 1.002)0.995 (0.989, 1.001)1.001 (0.994, 1.007)0.986 (0.980, 0.992)0.996 (0.991, 1.000)
> High school1.025 (0.928, 1.132)1.024 (0.946, 1.108)0.995 (0.896, 1.106)0.943 (0.846, 1.051)0.992 (0.889, 1.107)1.013 (0.937, 1.096)
Shortness of breath1.094 (1.073, 1.116)1.062 (1.046, 1.078)1.082 (1.058, 1.106)1.060 (1.044, 1.075)
Pain1.032 (1.010, 1.055)1.121 (1.101, 1.140)1.045 (1.021, 1.070)1.123 (1.103, 1.142)
GI symptoms0.987 (0.966, 1.008)1.018 (1.002, 1.034)0.990 (0.967, 1.014)1.018 (1.003, 1.033)
Fatigue0.999 (0.997, 1.001)0.994 (0.992, 0.996)0.998 (0.995, 1.001)0.994 (0.992, 0.996)
Raynaud’s0.983 (0.964, 1.002)1.028 (1.013, 1.042)0.984 (0.963, 1.005)1.028 (1.014, 1.043)
Skin score1.030 (1.025, 1.035)1.009 (1.005, 1.013)1.030 (1.025, 1.035)1.012 (1.006, 1.018)
Fingertip ulcers1.009 (0.989, 1.028)1.008 (0.991, 1.024)1.009 (0.988, 1.030)1.019 (0.996, 1.042)
Swollen joints1.004 (0.980, 1.028)1.010 (0.992, 1.028)0.999 (0.973, 1.024)0.998 (0.973, 1.024)
Tender joints0.996 (0.982, 1.009)0.993 (0.983, 1.003)1.005 (0.990, 1.020)1.023 (1.008, 1.039)
Creatinine1.036 (1.011, 1.062)1.012 (0.991, 1.032)1.035 (1.008, 1.063)1.008 (0.978, 1.039)
Deviance explained, %28.955.917.54.613.854.3