Objectives Screening for symptoms of postintensive care syndrome is based on a long list of questionnaires, filled out by the intensive care unit (ICU) survivor and manually reviewed by the health professional. This is an inefficient and time-consuming process. The aim of this study was to evaluate the feasibility of a web-based triage tool and to compare the outcomes from web-based questionnaires to those from paper-based questionnaires. Design A mixed-methods study. Setting Nine Dutch ICU follow-up clinics. Participants 221 ICU survivors and 14 health professionals. Interventions A web-based triage tool was implemented by nine ICU follow-up clinics. End users, that is, health professionals were interviewed in order to evaluate the feasibility of the triage tool. ICU survivors were invited to fill out web-based questionnaires 3 months after hospital discharge. Primary outcomes Outcomes of the questionnaires were merged with clinical data from a national quality registry to assess the differences in outcomes between paper-based and web-based questionnaires. Results 221 ICU survivors received an invitation to fill out questionnaires, 93 (42.1%) survivors did not respond to the invitation. Respondents to the web-based questionnaires (n=54) were significantly younger and had a significantly longer ICU stay than those who preferred the paper-based questionnaires (n=74). The prevalence of mental, physical and nutritional problems was high, although comparable between the groups. Health professionals’ interviews revealed that the software was complex to use (n=8) and although emailing survivors is very convenient, not all survivors have an email address (n=7). Conclusions Web-based screening software has major benefits compared with paper-based screening. However, implementation has shown to be rather difficult and there are important barriers to consider. Although different in age, the health status is comparable between the users of the web-based questionnaire and paper-based questionnaire.