Meaningful improvement thresholds in measures of pain and quality of life in oral lichen planus

Objectives: To evaluate the responsiveness of measures of pain and oral health-related quality of life (OH-QoL) in patients with oral lichen planus (OLP) and to determine thresholds for minimal important change (MIC) and minimal important difference (MID) for use in this patient population. Methods: Data from baseline and 4-month follow-up including Visual Analog Scale (VAS), Numerical Rating Scale (NRS), 14-item Oral Health Impact Profile (OHIP-14), 15-item and 26-item Chronic Oral Mucosal Disease Questionnaire (COMDQ-15; COMDQ-26) were collected from 157 patients with OLP. Responsiveness was assessed by testing hypotheses and calculating the area under the curve. MIC and MID were established based on triangulation of distribution-based and anchor-based estimates. Results: The results supported adequate responsiveness of VAS, NRS, COMDQ-15 and COMDQ-26 for use in OLP, while the OHIP-14 demonstrated relatively low sensitivity to detect improvement in the OLP status. Recommended meaningful improvement thresholds were as follows: VAS (MIC 16 mm; MID 18 mm), NRS (MIC/MID 2 points), OHIP-14 (MIC/MID 5 points), COMDQ-15 (MIC 5 points; MID 6 points) and COMDQ-26 (MIC/MID 9 points). Conclusion: This study provides some evidence of responsiveness as well as establishing meaningful improvement thresholds in scores of pain and OH-QoL measures in OLP.