Lay understanding of common medical terminology in oncology.

OBJECTIVE The purpose of this study was to replicate and extend an earlier study carried out in the UK of lay understanding of cancer-related terms in a Dutch sample, by (i) examining understanding of common terms relating to diagnosis, prognosis, and treatment and (ii) experimentally exploring the effect of medical jargon versus plain language use on individuals' perceived efficacy in interacting with oncologists, participating in medical decision making, and interpersonal trust. METHODS One hundred ninety-four lay people completed a questionnaire assessing (i) understanding, confidence in understanding, and worry after reading 10 scenarios presenting cancer-related terms and (ii) perceived communication efficacy, decision-making efficacy, and trust following a vignette portraying an oncologist using either jargon or plain language. RESULTS On average, participants understood a majority (6.8 ± 1.6) of cancer-related terms, yet only 2.2% understood all 10 terms correctly. Compared with incorrect understanding, correct understanding was generally related to higher confidence in understanding and to worry levels that better matched the scenarios. Language complexity did not significantly affect measures of perceived efficacy or trust. Overall confidence in understanding was significantly related to measures of perceived efficacy (p < 0.01). CONCLUSION Similar to the earlier UK study these results suggest that lay people's understanding of commonly-used terms in oncology is suboptimal. Moreover, confidence in understanding was related to perceived efficacy in participating in the consultation. Oncologists should attempt to correct patient misunderstanding to alleviate unnecessary worry and potentially facilitate patient participation.