BackgroundPatients’ perceptions and Oral Health-related Quality of life (OHRQoL) are important parts of dental treatment in all fields, including oral lichen planus (OLP) patients. A shortened version of the Oral Impact on Daily Performances (OIDP) might be more practical and feasible in clinical setting due to the busy nature of oral medicine clinics and staff availability to conduct the interview for data collection. The aim of the study was to develop a Thai version of shortened OIDP for assessing the OHRQoL in OLP patients.MethodsTwo types of shortened OIDP versions were tested in 69 OLP patients, one comprising the most commonly interfered with daily performances (OIDP-3 and OIDP-2) and another comprising either the highest frequency (OIDP frequency) or severity score (OIDP severity). The Numeric Rating Scale (NRS) and Thongprasom sign score were used to assess oral pain and clinical severity. Spearman rank-order correlation coefficients (rs) were used to demonstrate the associations between the shortened and original OIDP, pain, and clinical severity.ResultsOIDP-3 (Eating, Cleaning, and Emotional stability) and OIDP-2 (Eating and Emotional stability) were developed. The associations of the original OIDP with OIDP-3 and OIDP-2 (rs= 0.965 and 0.911) were significantly higher than those of the original OIDP with OIDP frequency and OIDP severity (rs= 0.768 and 0.880). The original OIDP, OIDP-3, and OIDP-2 were more significantly associated with pain compared with OIDP frequency and OIDP severity. The association between the clinical severity and oral impacts assessed by the original OIDP, OIDP-3, and OIDP-2 were similar and had higher correlation coefficients compared with those of OIDP frequency and OIDP severity.ConclusionOIDP-3 and OIDP-2 performed more similarly to the original OIDP than OIDP frequency and OIDP severity in assessing the OHRQoL of OLP patients.Trial registrationThe trial was registered at the Thai Clinical Trials Registry (TCTR identifier: TCTR 20190828002).