Patients have expressed concern about undergoing procedures involving trainees, even with direct attending physician supervision. Little literature has examined the effect of trainee involvement on patient outcomes.We aimed to evaluate the effect of trainee involvement on patient complications, immediate pain reduction, and fluoroscopic time for different fluoroscopic injection types.Retrospective review.Four academic outpatient institutions with Accreditation Council for Graduate Medical Education (ACGME)−accredited residency (physical medicine and rehabilitation, or anesthesiology) or fellowship (sports medicine or pain medicine) programs from 2000 to 2015.All patients receiving fluoroscopically guided hip (HI), sacroiliac joint (SIJI), transforaminal epidural (TFEI), and/or interlaminar epidural injections (ILEI, performed at only 1 institution).Outcome measures were examined based on the presence or absence of a trainee during the procedure.The primary outcome was the number of immediate complications, with secondary outcomes being fluoroscopic time per injection (FTPI) and immediate numeric rating scale percentage improvement.Trainees were involved in 67.0% of all injections (N = 7,833). Complication rates or improvements in numeric rating scale scores showed no significant differences with trainee involvement for any injection type (P > .05). Trainee involvement was associated with increased FTPI for ILEIs (18.2 ± 10.1 seconds with trainees versus 15.1 ± 8.5 seconds without trainees, P < .001), but not for HIs (P = .60) or SIJIs (P = .51). Trainee involvement with TFEIs was dependent on institution for outcome with respect to FTPI (P < .001), with 28.1 ± 17.9 seconds with trainees and 32.1 ± 22.1 seconds without trainees (P = 0.51).This large multicenter study of academic institutions demonstrates that trainee involvement in fluoroscopically guided injections does not affect immediate patient complications or pain improvement. Trainee involvement does not increase fluoroscopic time for most injections, although there is an institutional difference seen. This study supports the notion that appropriate trainee supervision likely does not compromise patient safety for fluoroscopically guided injections.II