IntroductionBlood sampling for therapeutic drug monitoring (TDM) can be distressing for children; salivary sampling, a less invasive alternative, may be as reliable and can facilitate sampling at home, thus potentially meaning fewer hospital visits. In the absence of a validated tool to assess child-patients’ views on salivary versus blood sampling following kidney transplantation, we developed/pilot tested a questionnaire with transplanted patients aged 5-18 years. This paper discusses preliminary development/pilot testing of the ChYPSS MethodsTwo short questionnaires using age appropriate designs (for up to 8 years; 9-18 years) involving closed and open-ended questions were administered in two phases during transplant clinics4. To ensure participation did not inconvenience families by intruding in or delaying consultations, choice was offered regarding: version (paper or laptop), timing (before/after clinic appointments), venue, for completionResultsSixteen patients participated in phase 1; twelve found ChYPSS easy to use in terms of layout, wording, and response method and completed all items; four suggested some alterations. The ChYPSS was refined accordingly before administering to another 15 patients in phase 2 who all found it easy to use in terms of layout, wording, and response method. Overall, 30 selected the paper version and one the computer version. Data were managed using SPSS, Framework Analysis and Excel. Six patients indicated a preference for blood sampling in hospital (reasons included opportunities to discuss ‘problems with renal team’), 15 would prefer home-based salivary sampling (reasons included ‘missing less school’), six had no preferences. DiscussionPatients (and their parents) thought the revised ChYPSS was potentially useful to determine views on blood and salivary sampling. Further research is needed to evaluate the CHYPSS using a larger sample of patients for whom salivary sampling for TDM is an option, to allow psychometric testing and factor analysis to be carried out.