Skip to main content

Table 4 IRT coefficients of each item extracted from the graded response model (Samejima) and fit-adjusted parameters (chi-square)

From: Dimensionality and psychometric analysis of DLQI in a Brazilian population

Item a b1 b2 b3 chi-square p
q1 1.40 −0.69 0.48 1.48 44.69 0.04
q2 2.55 −0.21 0.43 1.10 17.97 0.96
q3 4.22 0.18 0.44 1.27 15.49 0.99
q4 2.36 0.22 0.83 1.43 10.93 0.99
q5 4.74 0.14 0.68 1.20 13.62 0.99
q6 1.79 0.87 1.36 1.94 68.74 < 0.01
q7 1.21 0.77 1.34 2.13 95.66 < 0.01
q8 1.75 0.73 1.50 2.37 23.03 0.81
q9 1.70 1.06 1.65 2.18 14.19 0.99
q10 1.83 0.78 1.51 2.28 14.61 0.99
  1. (AIC = 22.157; BIC = 22.364; X2 = 318.9; p = 0.22)