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Objectives A challenge of examining patient outcomes in clinical research is determining if the observed differences represent a statistically significant change and, if so, whether this constitutes a clinically meaningful change for patients. There is currently no estimate for minimally clinically important difference (MCID) for the six-minute walking distance (6MWD) for populations with pulmonary hypertension associated with interstitial lung disease (PH-ILD). This study sought to employ a novel approach to MCID estimation, employing validated techniques to elicit clinical experts’ judgement.Methods The study was piloted with two clinical experts, and five clinical experts from the UK and Germany with experience in PH-ILD or ILD participated in the workshop. They were asked to construct a histogram using the ‘chips and bins ‘method. The experts were asked to complete two MCID elicitation exercises. The MCID tasks were interspersed with a facilitated group discussion to examine between-expert variability.Results The first MCID estimates ranged from 17.5 m (SD = 1.4 m) to 47.1 m (SD = 11.8 m) with a pooled distribution of 31.9 m (SD = 12.4). The MCID pooled distribution for the second elicitation was 31 m (SD = 8.7 m). The individual responses ranged from 24.8 m (SD = 2.0 m) to 40.6 m (SD = 8.7 m). One expert expressed they were uncertain in their estimate being valid explained by (1) their experience with only ILD patients and (2) the observed variability in patient performance on the 6MWD test. The expert made contradictory comments, indicating they did not fully understand the task. If this expert’s response is excluded, the MCID would be 28.6 m (SD 6.9).Conclusion According to the study, the MCID lies between 24.8 m to 40.6 m. All experts discussed uncertainty due to the severity of PH was unspecified which could explain the range provided by the experts.