Development and validation of a measure of sensory sensitivity - the Sensory Sensitivity Profile: a Rasch analysis.

Objective: Pain hypersensitivity and hypersensitivity to other sensory modalities (visual, auditory, olfactory, and tactile) are considered defining features in nociplastic pain states. A self-report measure of sensory sensitivity may help to characterize sensory profiles across pain populations. This study aimed to evaluate the psychometric properties of a newly developed Danish nine-item Sensory Sensitivity Profile (SSP) questionnaire in patients with fibromyalgia.

Method: Baseline assessments from a randomized controlled trial population of 200 individuals with a confirmed diagnosis of fibromyalgia who had completed the SSP were used in this study. Rasch analysis was applied to the dataset, allowing for a detailed analysis of the rating scale properties and further aspects of validity, including fit of individual scale items to a unidimensional model indicating assessment of a single construct, and assessment of the instrument's ability to provide precise and reliable measures of sensory sensitivity.

Results: The Rasch analyses revealed that the 0-3 ordinal rating scale of the SSP had sound psychometric properties, and supported the idea that the nine SSP items contributed towards measurement of a single construct. The study population exhibited expected and valid response patterns, with sensitivity to sound and pain being the most endorsed items. The SSP demonstrated adequate precision and reliability of item difficulty estimates and person sensory sensitivity measures when applied in our study population.

Conclusion: From the perspective of the Rasch measurement model, this first version of the SSP demonstrated adequate psychometric properties for characterizing and quantifying sensitivity to specific sensory modalities in patients with fibromyalgia.