a. p-value is from the pairwise comparison of methotrexate monotherapy and Humira/ methotrexate combination therapy using the Mann-Whitney U test. b. p-value is from the pairwise comparison of Humira monotherapy and Humira/ methotrexate combination therapy using the Mann-Whitney U test c. p-value is from the pairwise comparison of Humira monotherapy and methotrexate monotherapy using the Mann-Whitney U test