Box 1.

Two Cases and Their Predicted Score on the RPQ Scale According to Our Prediction Model

Case 1: Male patient, 65 years, 23 years of education with pre-injury headache or migraine, a pre-injury psychiatric disorder, a prior TBI, LOC, and PTA.

Predicted value total RPQ scale after 6 months = 14.45 (intercept) + (0.74*0) + (0.05*65) + (−0.79*23) + (2.07*1) + (3.73*1) + (3.71*1) + (−0.47*0) + (−0.38*0) = 9.04 (95% CI: 4.57 – 13.50)

Case 2: Female patient, 30 years, 10 years of education with pre-injury headache or migraine, a pre-injury psychiatric disorder and no prior TBI, LOC and PTA

Predicted value total RPQ scale after 6 months = 14.45 (intercept) + (0.74*1) + (0.05*30) + (−0.79*10) + (2.07*1) + (3.73*1) + (3.71*0) + (−0.47*1) + (−0.38*1) = 17.45 (95% CI: 13.00 – 21.90)

Expected scores can be calculated with the regression formula in the footnote of Table 4. The 95% Confidence interval can only be calculated with advanced statistical software.