Study	Prognostic factors								Adjusted results for interim PET
	Interim PET	Age	Gender	Disease stage	B symptoms	Bulky disease	IPS	Other study‐specific factors
Casasnovas 2019	x	‐	x	x	x	x	x	x	Multivariable analysis not reported separately for standard treatment group.
Gallamini 2014	x	‐	‐	‐	‐	‐	‐	x	PET2 HR N/A, P < 0.01 (Sig. 0.000), 95% CI 3.136 to 7.917 Comment: Adjusted results indicate the independent prognostic impact of interim PET2.
Hutchings 2005	x	‐	‐	x	‐	‐	‐	x	Early interim PET Wald 19.05, HR N/A, P‐value = 0.00007 Comment: Adjusted results indicate the independent prognostic impact of early interim PET.
Hutchings 2006	x	‐	‐	x	‐	‐	‐	x	Model 1 (interim PET2 + clinical stage + extranodal disease) PET2 HR = 36.281 (95% CI 7.179 to 183.4), P < .001 Model 2 (interim PET2 + extranodal disease) PET2 HR = 36.887 (95% CI 7.338 to 185.4), P < .001 Comment: Adjusted results indicate the independent prognostic impact of interim PET2.
Kobe 2018	x	‐	‐	‐	‐	‐	x	x	Interim PET‐positivity (DS 4) HR 2.4 (95% CI 1.4 to 4.1), P = 0.002 Comment: Adjusted results indicate an independent prognostic impact of PET2.
Mesguich 2016	x	‐	‐	x	‐	x	‐	‐	Model 1 (interim PET + disease stage) Positive interim PET HR = 3.73 (95% CI 1.35 to 10.35), P = 0.0112 Model 2 (interim PET + bulky disease) Positive interim PET HR = 3.62 (95% CI 1.30 to 10.05), P = 0.0138 Comment: Adjusted results indicate the independent prognostic impact of interim PET.
Rossi 2014	x	‐	‐	‐	‐	‐	‐	x	SUVmax PET0‐PET2 Relative risk = 7.9 (95% CI 2.9 to 22.9), P = 0.0001 Comment: Adjusted results indicate the independent prognostic impact of SUVmax PET0‐PET2.
Simon 2016	x	‐	‐	‐	‐	‐	‐	x	Interim PET‐positivity HR = 17.74, P < 0.001, 95% CI 6.61 to 47.57 Comment: Adjusted results indicate the independent prognostic impact of PET2.
x = prognostic factor considered for adjustment in the final model ‐ = prognostic factor was not considered in the final model