BACKGROUND: The framing effect has been demonstrated in a variety of settings. This study aimed to determine whether framing of complication risk in total hip arthroplasty (THA) and long-term patient satisfaction rates in total knee arthroplasty (TKA) influences patient decision-making and 'worry' using hypothetical vignettes. METHODS: Two cross-sectional survey studies were undertaken, one based on a THA vignette and one based on a TKA vignette. Participants were randomized into a positive-framing or negative-framing group and asked to read the vignette. They were then asked to indicate whether they would proceed with surgery, and to self-report their degree of 'worry' about surgery. For the THA vignette, the positive-framing group was informed '98 % of people will have no major complications' while the negative-framing group was informed that '2 % of people will have a major complication'. For the TKA vignette, the positive-framing group was informed '80/100 of people will be happy ... once they have recovered' and the negative-framing group was informed '20/100 people will be unhappy ... once they have recovered'. The vignettes were otherwise identical. The primary outcome was the decision to proceed with surgery. The secondary outcome was self-reported 'worry' about surgery. RESULTS: For the THA vignette (622 individuals) 294/310 (95 %) indicated they would proceed with surgery in the positive-framing group while 275/312 (88 %) indicated they would proceed with surgery in the negative-framing group (p = 0.0037). For the TKA vignette (623 individuals), 302/311 (97.1 %) indicated they would proceed with surgery in the positive-framing group and 280/312 (89.7 %) indicated they would proceed with surgery in the negative-framing group (p = 0.0003). Self-reported 'worry' differed based on positive or negative framing in both surveys. CONCLUSIONS: Framing of complication risk and long-term outcomes influences patient decision-making and 'worry' in a THA and TKA vignette. This has implications for shared decision-making and informed consent.