Abstract
Background Patients with Hereditary Spastic Paraplegia (HSP), an inherited neurodegenerative condition leading to lower limb weakness and spasticity, have reported lower quality of life (QoL) indices compared to healthy controls, influenced by unique aspects of the condition. To explore this, we aimed to design a QoL survey specific to HSP (HSPQoL) by supplementing a widely used generic QoL scale, SF-36, with additional HSP-specific questions. The initial stage of question design involved a literature review and expert consensus using the modified Delphi method.
Objective To further refine the additional HSP-specific QoL questions with consumer consultation.
Method We recruited patients with HSP to participate in cognitive interviews using a think-aloud and verbal probing approach. Interviews were recorded, transcribed, and de-identified. Quotes were analysed according to themes: item comprehension, response options, wording clarity, and item relevance. The ten additional questions developed to date were revised based on patient views.
Results Five patients (F:M 3:2, mean age 61.8 years) with HSP were interviewed to explore ten questions during the sessions. Five questions were modified to improve clarity, item comprehension, response options and item relevance. Modifications included changes to wording and response options, and additional explanations to clarify purpose of question. Two questions were removed due to poor clarity and patient-identified concerns regarding suitability. A total of eight additional questions are to be included in the final HSPQoL.
Conclusions Validity and reliability of the HSPQoL rating scale will now be tested in a larger cohort of patients with HSP.
