Inter-professional variability in the assignment and recording of acute toxicity grade using the RTOG system during prostate radiotherapy.

Background And Purpose: To compare the routine acute toxicity documentation practices of therapists and oncologists using the RTOG lower GI and GU scales.

Methods And Materials: Ninety consecutive prostate radiotherapy patients were identified. The weekly urinary and rectal acute toxicity grades routinely documented by therapists and oncologists were collected retrospectively from radiotherapy charts. These data were paired together, and compared between the professional groups.

Results: Only RTOG acute toxicity grades between 0 and 2 were recorded by either group. The overall rate of documentation was high (97% therapists/86% oncologists), but the rate of quantitative documentation was low from the oncologists (46%) who used a free-form text field for recording purposes. There was no significant difference in the incidence of maximum grade of acute toxicity reported by either professional group (p>0.1). There was good RTOG score concordance between the observer groups (kappa=0.756), with pair-wise absolute agreement in 76%. Pair-wise discrepancies between the observers were commonly attributable to differences in the time/date of assessment.

Conclusions: Despite some methodological limitations, this study found that therapist-assessed RTOG acute toxicity grades demonstrated a good level of agreement with the grades assigned by their oncologist colleagues.