We read the article by Kim et al1 with interest and would like to highlight some concerns regarding their data and conclusions. The title and purpose of the study seems to indicate outcomes for a particular surgeon group (residents in training); however, the conclusions are not supported by the data. Amongst 1582 procedures, after excluding surgery complicated with vitreous loss, 305/1582 procedures were performed by attending surgeons and further excluded from analysis. The outcomes of these 305 surgeries is reported in the discussion as having an incidence of first postoperative day intraocular pressure (IOP) elevation no higher than the trainee-performed surgery (P1⁄4 0.94, w-test). The authors have surprisingly chosen to present the study as a consecutive case series instead of a more useful comparative study. There is a discrepancy in the use of ophthalmic viscosurgical device (OVD). The methodology states use of two agents: Healon (1% sodium hyaluronate) initially in 2001 to 2005 and thereafter Duovisc, which is composed of two OVDs, the cohesive Provisc (1% sodium hyaluronate) and dispersive Viscoat (sodium chondroitin sulphate 4%–sodium hyaluronate 4%). However, in Table 2 the OVD reported as used is Healon GV, a hyaluronic acid product with a 10-times higher viscosity than Healon, preferred in complicated procedures (vitreous pressure, flat anterior chamber, so on) and thus probably chosen for resident surgery. The effect of OVDs with higher molecular weight and viscosity on postoperative IOP is well documented.2,3 This may well explain the reason for this case series having a higher postoperative IOP 24 h after cataract surgery (22%, 423 mm Hg and 14.9%, 426 mm Hg) than the previously reported values of 2.57%4 and 11.8%,5 respectively. The effect of trainee surgeons on early IOP rise after cataract surgery can be a consequence of relatively more manipulations, residual OVD, and subsequent increased inflammation. This hypothesis maybe better supported by data on central corneal thickness, aqueous flare, surgery duration, phacoemulsification power etc as well as a comparative case–control study design.